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Journal of Jilin University(Earth Science Edition)
ISSN 1671-5888
CN 22-1343/P
主 任:蒋 函
编 辑:邱殿明 王晓丽
    刘 莉
电 话:0431-88502374
E-mail:xuebao1956@jlu.edu.cn
地 址:长春市西民主大街938号
    (130026)
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Forward Modeling of Airborne Electromagnetic  Induced Polarization Effect in Time-Domain Based on Debye Model
Zhang Xinchong, Yin Changchun
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1573-1581.   DOI: 10.13278/j.cnki.jjuese.20220244
Abstract2497)      PDF(pc) (3666KB)(59)       Save

The time-domain airborne electromagnetic (AEM) method is an efficient geophysical exploration technique. Yet, due to the presence of the induced polarization (IP) effect, electromagnetic (EM) data from late-time channels often exhibit a phenomenon known as sign reversal. The traditional imaging and inversion methods without considering the IP effect cannot recover the real electrical structure of the underground, so it is necessary to develop the EM forward and reverse modeling technology with IP effect. This study introduces a three-dimensional (3D) forward algorithm for AEM with IP effect in the time-domain built upon the unstructured finite-element method. To capture the IP effect within the medium, we use the Debye model, transforming it into a derivative form in the time-domain through frequency-time conversion. For temporal discretization, an unconditionally stable second-order backward Euler's scheme is applied. Maxwell’s equations are discretized in space using a vector finite element method based on an unstructured tetrahedral mesh. The algorithm's accuracy is verified through a comparison with the 1D semi-analytical solution of the uniform half-space model. We compute EM responses for both a half-space and 3D geological formations under various polarization conditions. We observe that the polarization characteristics of surrounding rocks and anomalous bodies can be effectively identified according to the attenuation characteristics of the AEM response curves. In addition, by studying the characteristics of the influence of IP parameters on the time-domain AEM system, we show that the larger the resistivity of the geological body or the larger the chargeability, the stronger the IP effect.


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Intelligent Identification Method of Reservoir Lithology in Central Depression of Songliao Basin

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Wang Tingting, Sun Zhenxuan, Dai Jinlong, Jiang Jilu, Zhao Wanchun
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1611-1622.   DOI: 10.13278/j.cnki.jjuese.20220304
Abstract2491)      PDF(pc) (6115KB)(91)       Save

The recognition and classification of lithological information hold significant importance for categorizing oil and gas reservoirs and evaluating the compressibility of reservoir rocks. This study presents enhancements to the deep learning  network U-Net and conducts a comparative validation using experimental data from  central depression  of  Songliao Basin. We propose a more suitable feature attention fusion Unet (FAF-Unet) designed for well logging data. The selection of logging data primarily involves sensitivity analysis to identify characteristic parameters, including natural potential, acoustic time difference, photoelectric absorption cross-section index, wellbore diameter, density, natural gamma, and deep and shallow lateral resistivity. These parameters are analyzed to understand reservoir rock lithology. FAF-Unet is a network that amalgamates residual blocks and channel attention mechanisms. Residual blocks can better retain the data with lower-level features of the depth direction, and channel attention mechanisms can make up for the problem of ignoring the connection between  horizontal channels during vertical convolution. Comparing the accuracy and recall of six recognition methods, including support vector machine, decision tree, U-Net, U-Net with effective channel attention (ECA) mechanism, U-Net with residual block (Res-Unet), and FAF-Unet with both ECA and residual block, experimental results demonstrate that FAF-Unet achieves an accuracy and recall rate exceeding 89.00%. FAF-Unet outperforms the other five methods in terms of recognition performance and exhibits a narrower fluctuation range between accuracy and recall.


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Seismic Data Reconstruction Based on Joint Accelerated Proximal Gradient and Log-Weighted Nuclear Norm Minimization

Yang Fan , Wang Changpeng, Zhang Chunxia, Zhang Jiangshe, Xiong Deng
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1582-1592.   DOI: 10.13278/j.cnki.jjuese.20220305
Abstract2490)      PDF(pc) (18003KB)(67)       Save

Due to surface obstacles or economic constraints, seismic data recorded is often incomplete. Consequently, seismic data reconstruction is an important topic in seismic research. This study presents a seismic data reconstruction approach based on joint accelerated proximal gradient and log-weighted nuclear norm minimization. The process begins by subjecting the original seismic data to low-rank preprocessing through texture-patch operators. Subsequently, the accelerated proximal gradient algorithm is employed for an initial reconstruction of the low-rank seismic data. Finally, an algorithm based on the log-weighted nuclear norm is presented to tackle the optimization problem and reconstruct the missing data. For synthetic seismic data and real seismic data, the reconstruction results of the joint accelerated proximal gradient and log-weighted nuclear norm method have improved both in quantitative and qualitative analysis: The signal-to-noise ratio of the synthetic data set with a 40% missing rate is 26.135 7 dB and the reconstruction error is 6.789 4; The signal-to-noise ratio of the Mobil Avo Viking Graben Line 12 data set with a 30% missing rate is 17.247 8 dB and the reconstruction error is 4.762 5; The signal-to-noise ratio of the Netherlands F3 data set with a 60% missing rate is 26.058 1 dB and the reconstruction error is 7.464 1.


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Eliminating Low-Frequency Noise in Reverse-Time Migration Based on DeCNN

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Wan Xiaojie, Gong Xiangbo, Cheng Qiao, Yu Minghao
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1593-1601.   DOI: 10.13278/j.cnki.jjuese.20220251
Abstract2467)      PDF(pc) (14060KB)(44)       Save

Reverse-time migration (RTM) is widely employed for its ability to produce high-resolution imaging results. Nevertheless, wavefield extrapolation based on the two-way wave equation often leads to pronounced low-frequency noise under cross-correlation imaging condition. This issue significantly impacts the quality of the resulting images. In this study, we introduce a convolution-deconvolution neural network (DeCNN) built upon the U-Net architecture to mitigate the presence of low-frequency noise in RTM. We utilize source-normalized imaging results with  low-frequency noise as training data, and the Laplace filtering results   as labels to abtain  the neural network model, grounded in a data-driven approach. The comparison results of   model trials and transfer learning demonstrations highlight the superior denoising proficiency of  DeCNN. It outperforms  U-Net, effectively suppressing noise in scenarios such as the transfer  SEG/EAGE standard salt dome model and  Marmousi model. In contrast to conventional techniques aimed at mitigating low-frequency noise through up and down traveling wave decomposition, DeCNN  can input the source-normalized imaging results into the network after training, and the network can output high resolution imaging results in seconds. The efficiency is much higher than that of conventional low-frequency noise suppression methods using wavefield decomposition, and it has certain advantages in noise suppression effect.


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Sand Body Thickness Prediction of Underwater Distributary Channel Based on CV-XGBoost Method

Bai Qinglin, Liu Xuanliang, Zhang Junhua, Wang Fujin, Liu Zhongwei, Jiao Hongyan
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1602-1610.   DOI: 10.13278/j.cnki.jjuese.20220258
Abstract2448)      PDF(pc) (5435KB)(36)       Save

Aiming at the problems of underwater distributary channel sand body, such as thin single layer thickness, serious superimposition and crossing, strong lateral heterogeneity, and poor consistency of well seismic relationship, this study presents a prediction method of CV-XGBoost reservoir thickness based on cross validation. Firstly, correlation analysis and multicollinearity evaluation are used to remove redundant attributes, then the model training and parameter set optimization are carried out, and finally thickness prediction is carried out with verification set. The results show that: 1) For reservoir prediction with few samples, it is necessary to do cross validation to improve the accuracy of reservoir prediction; 2) XGBoost uses a regular term with the second order partial derivative to control the convergence progress of the model, and its prediction accuracy is better than that of conventional LASSO (least absolute shrinkage and selection operator) regression, GBDT (gradient boosting decision tree) and SVM (support vector machine) methods; 3) The reservoir prediction results with low verification set ratio can be used to understand the macro distribution of sand body, and the higher verification set ratio is helpful to improve the accuracy of sand body description; 4) The average amplitude, average energy, arc length and dominant frequency in this study area are the attributes that contribute greatly to thickness prediction.

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Application of Petrophysical Properties in the Geological Corridor of Western Liaoning Province to Petrogenesis

Li Yang, Han Liguo, Meng Zhaohai, Xu Xuechun, Li Fengting, Dong Siyuan, Zhou Shuai
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1623-1634.   DOI: 10.13278/j.cnki.jjuese.20220196
Abstract2445)      PDF(pc) (8910KB)(42)       Save

This study focuses on measuring the physical parameters of rock samples sourced from diverse geological units within the geological corridor of western Liaoning Province. For igneous and sedimentary rocks, we establish both qualitative and semi-quantitative relationships between density, elastic wave velocity, magnetic susceptibility, resistivity and spectral data, and study the correlation between petrophysical properties and rock characteristics, so as to study the diagenetic environment of rocks. Through statistical analysis of correlation coefficient curves specific to different rock types, we present a comprehensive summary of the interplay between rock types and strength of correlation coefficient between spectral reflectance and the intensity of correlations with density, elastic wave velocity, magnetic susceptibility, and resistivity. According to the characteristics of strength of correlation, it is analyzed that the difference of diagenetic environment leads to different physical properties of different rocks. The physical sedimentary environment of sedimentary rocks fosters a robust correlation between its spectral reflectance and both density and elastic wave velocity. The stable diagenetic setting of igneous rock yields a strong connection between its spectral reflectance and magnetic susceptibility. The spectral reflectance of both sedimentary and igneous rocks exhibits a positive correlation with density and elastic wave velocity.

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Spatial-Temporal Differentiation Characteristics of Urban Construction Land Expansion in Liaoning Province

Guo Lina, Zi Fengjiao, Jiang Guanghui, Zhao Yanxia, Wang Gang
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1635-1650.   DOI: 10.13278/j.cnki.jjuese.20220287
Abstract2444)      PDF(pc) (10000KB)(65)       Save
Understanding the characteristics of urban land expansion is essential for managing the uncontrolled growth of construction areas during the urbanization process. Four representative cities, namely Shenyang, Dalian, Chaoyang, and Dandong, located in various directions within Liaoning Province, were chosen for this study. Employing remote sensing image data from 1990, 2000, 2010, and 2020, the research employed metrics such as the proportion of construction land, expansion intensity index, expansion intensity difference index, and the public edge measurement method to investigate the distinctive attributes of urban construction land within the designated area. The findings reveal significant variations in the spatial expansion of construction land across the four cities. Between 1990 and 2020, the overall share of construction land expanded considerably from 4.74% to 11.58%. During this period, the order of expansion intensity shifted from high to low as follows: Shenyang, Dalian, Dandong, and Chaoyang. Notably, Dalian exhibited rapid expansion, Shenyang and Dandong initially underwent slow expansion, transitioning to higher rates during the second and third phases, Chaoyang expanded from low speed to high speed, and then to medium speed. Over the same period, the divergence in urban expansion trends of  Shenyang, Chaoyang, and Dandong diminished gradually, while Dalian experienced an increasing discrepancy in its expansion pattern. The four cities employed a combination of three expansion modes, with predominant reliance on sprawl development, followed by enclave development, infill development was relatively minimal. The overarching urban growth trend revolved around outward development. However, distinct development needs led to variations among the cities.
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Neoarchean TTG Gneisses Generated Through Amphibole-Dominated Fractionation in Guyang, Inner Mongolia: Evidence from Elemental Geochemistry and Thermodynamic Modelling
Tong Xin, Shi Jianrong, Wang Huichu, Zhang Jiahui, Ren Yunwei
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1734-1759.   DOI: 10.13278/j.cnki.jjuese.20230205
Abstract1750)      PDF(pc) (62357KB)(68)       Save
 In Guyang, Inner Mongolia, a significant occurrence of Late Neoarchean (quartz) diorite-tonalite-trondhjemite-granodiorite (DTTG) rock assemblages has been identified. LA-ICP-MS zircon U-Pb dating has yielded crystallization ages of (2 504±11) and (2 514±7) Ma for the quartz dioritic and tonalitic gneisses, respectively. Additionally, the dioritic gneisses exhibit inherited zircon ages of ca. 2.6 Ga. The quartz dioritic (D) gneisses in Guyang display a relatively low w(SiO2) (62.08%-62.62%), Sr/Y ratios (23.3-39.8), and elevated concentrations of w(MgO) (2.08%-3.06%) and w(TFe2O3) (5.43%-6.01%). Notably, these rocks demonstrate either negligible or weak Eu negative anomalies (Eu/Eu* = 0.91-0.98) and show subtle differentiation between light and heavy rare earth elements ((La/Yb)N = 7.59-21.60). These features are indicative of island arc calc-alkaline geochemical signatures. Combining these characteristics with zircon Hf isotope compositions suggests that the late Neoarchean diorites likely formed through crustal partial melting under relatively low-pressure and shallow conditions. In contrast, the late Neoarchean tonalitic-trondhjemitic (TT) gneisses in the Guyang area exhibit higher w(SiO2) (67.95%-77.01%), elevated Sr/Y ratios (120.00-941.00), and lower w(MgO) (0.14%-1.29%) and w(TFe2O3) (0.63%-2.66%). They also feature significant Eu positive anomalies (Eu/Eu* = 1.48-8.73) and prominent differentiation between light and heavy rare earth elements ((La/Yb)N = 29.70-140.00). While the consensus attributes the origins of TTG rocks to partial melting of hydrated altered basalts, the geochemical signatures of the   Late Neoarchaean (quartz) diorite-tonalite-trondhjemite (DTT) rocks in the Guyang area allude to fractional crystallization of amphibole. A mixing simulation involving Guyang cumulative hornblendite and trondhjemite accurately reproduces the composition of quartz dioritic gneisses in the Guyang area. Thorough thermodynamic and trace element quantitative modelling reveals that the Late Neoarchean tonalic-trondhjemitic rocks likely formed through multistage fractional crystallization from dioritic magma in a water-rich and relatively low-pressure condition. Amphibole is the primary mineral phase involved in fractional crystallization, with minor amounts of plagioclase and sphene. The high whole-rock Sr/Y and Eu/Eu* values do not indicate sufficient conditions for a relatively high-pressure source.
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In-Situ Trace Elements Characteristics of the Scheelite and Metallogenic Significance on Skarn Tungsten Deposits in Eastern Jilin and Heilongjiang Province, NE China
Ren Yunsheng, Li Jingmou, Hao Yujie, Xu Wentan
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1706-1721.   DOI: 10.13278/j.cnki.jjuese.20230232
Abstract1719)      PDF(pc) (22909KB)(81)       Save
The skarn-type scheelite deposit is an important type of tungsten deposits in eastern Jilin and Heilongjiang of Northeast (NE) China. The large-scale Cuihongshan Wo-polymetallic deposit in Xunke area of Heilongjiang Province and medium-scale Baishilazhi scheelite deposit in Wangqing area of Jilin Province are two representative skarn deposits. To determine their ore-forming fluid characteristics and metallogenic mechanism, scheelite single minerals were selected from these two representative deposits for in-situ LA-ICP-MS trace elements analysis. The results show that the scheelite in Cuihongshan deposit was formed in a Na- and Nb-rich ore-forming fluid system with left-dipped rare earth element (REE) distribution patterns and weak positive Eu anomalies. The substitution of REE3+ for Ca2+ in scheelite from Cuihongshan deposit can be accounted for the substitution mechanism: 2Ca2+ = REE3+ + Na+ and Ca2+ + W6+ = REE3+ + Nb5+. The scheelite in Baishilazi deposit was formed in a Na- and Nb-poor ore-forming fluid system with right-dipped REE distribution patterns and positive Eu anomalies. The substitution mechanism of REE3+ for Ca2+ in scheelite of Baishilazi deposit is 3Ca2+ = 2REE3+ + □Ca (where □ is a site vacancy). The obvious correlation between EuN and Eu*N and the high Mo content in scheelite samples indicates that the ore-forming fluids in two skarn-type tungsten (-polymetallic) deposits in eastern Jilin and Heilongjiang are oxidizing fluids. The Eu anomalies of scheelite in these two deposits are higher than those of their ore-forming intrusions, indicating that water-rock reaction occurred during the fluid evolution. The obvious correlation of Y and Ho contents between the scheelite in different deposits and their ore-forming intrusions, as well as the differences between Y/Ho and La/Ho, reveal that their initial ore-forming fluids are derived from magmatism, and water-rock reaction and fluid mixing occurred during the fluid evolution. Due to data from this studies and previous references, it can be concluded that the water-rock reaction and fluid mixing during ascending of the magmatic hydrothermal are major mechanisms of scheelite mineralization in the skarn-type tungsten (-polymetallic) deposit in eastern Jilin and Heilongjiang.
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Discovery, Geological Characteristics, Chronology and Metallogenic Geological Background of Gema Pb Polymetallic Deposit in Tibet

Yue Guoli, Li Min, Zhai Wenjian, Yang Changqing, Lü Guojuan, Zhao Huan,
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1467-1482.   DOI: 10.13278/j.cnki.jjuese.20220109
Abstract1707)      PDF(pc) (10405KB)(33)       Save

The Gema Pb polymetallic deposit was discovered by our team in 2010. It is currently the only medium-sized Pb-Zn-Ag polymetallic deposit in the eastern section of Bangong Lake-Nujiang metallogenic belt. The deposit is located in the eastern section of the Anglonggangri-Bange-Tengchong magmatic arc zone. The ore bodies are produced in the surrounding rocks of the outer contact zone of the Early Cretaceous granodiorite in the form of veins. The shapes and locations of the ore bodies are strictly controlled by two groups of faults in the nearly east-west and northwest directions. The ore-bearing surrounding rocks are sandstone and siltstone of the Mali Formation (hornfelization) of the Middle Jurassic. Based on the geological characteristics of the Gema Pb polymetallic deposit and the studies of the geochemistry of the surrounding rocks and ores, and the LA-ICP-MS zircon U-Pb chronology of granodiorite, this paper examined the source of ore-forming materials, the ore-forming age and the ore-forming geological background, also discussed the ore-forming process of the deposit, and established a preliminarily metallogenic geological model of the Pb-Zn-Ag polymetallic deposit in the eastern section of the Bangong Lake-Nujiang  metallogenic belt. The results show that the granodiorite in the area has low silicon, high aluminum and relatively rich potassium, which is the product of magmatism in the subduction stage before plate collision. The LA-ICP-MS zircon U-Pb dating of granodiorite yields an age of (119.86 ± 0.45) Ma, indicating an Early Cretaceous diagenetic age. The rare earth element (REE) of granodiorite, ore and surrounding rocks show enrichment in light REEs, depletion in heavy REEs, and a negative Eu anomaly, suggesting a common origin. Compared to the abundance values of Chinese continental crust, the granodiorite contains relatively enriched Pb and Ag, while Zn is deficient. In the metamorphic siltstone of Mali Formation, Pb and Ag are extremely strong enriched elements, and Zn is also strongly enriched. The ore-forming materials of this deposit are derived not only from granodiorite but also from the surrounding rocks of Mali Formation, indicating obvious “double source” feature. The deposit was formed in an island arc environment before the closure of the Bangong Lake-Nujiang Ocean basin. The ore forming age is Early Cretaceous, and the genetic type of the deposit is a post-magmatic hydrothermal deposit.


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 Prediction of Shallow Underground Temperature Based on the PSO-XGB Hybrid Optimization Technique: A Case Study of Changchun City
Yu Ziwang, Zheng Tianqi, Cheng Yuxiang
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1907-1916.   DOI: 10.13278/j.cnki.jjuese.20230263
Abstract1704)      PDF(pc) (9208KB)(46)       Save
Accurate prediction of shallow underground temperature is of great significance for reducing investment risks and promoting the development and utilization of shallow geothermal energy. In this study, a hybrid model based on particle swarm optimization (PSO) and extreme gradient boosting (PSO-XGB) was developed and compared with single models including K-nearest neighbors (KNN), support vector regression (SVR), random forest (RF), and extreme gradient boosting(XGB). Firstly, 54 sets of borehole data were collected, and the dataset was expanded using Kriging interpolation. Latitude and longitude coordinates, annual average rainfall, annual average temperature, and distance to faults were used as input features for predicting the temperature at a depth of 100 meters underground. Then the performance of the models was evaluated using metrics such as root mean squared error, mean absolute error, coefficient of determination, andmean squared error. The results showed that the PSO-XGB hybrid model outperformed the single models in terms of predictive performance. The ERMS is 0.070 6, the EMA is 0.054 9, the R2 is 0.962 0, and the EMS is 0.005 0, which is significantly higher than the other models in terms of precision and degree of fitting. Therefore, the PSO-XGB hybrid model is superior to the single model in prediction performance.
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Characteristics of Groundwater Level Dynamic Evolution and Influence Factors in Mountain-Front Alluvial Plain of   Hutuo River in Shijiazhuang
Yan Baizhong, Gai Junbai, Wang Xinzhou, Zhan Xinkai, Ma Miaomiao
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1880-1891.   DOI: 10.13278/j.cnki.jjuese.20230255
Abstract1694)      PDF(pc) (8709KB)(65)       Save
 In order to analysis the temporal and spatial evolution characteristics and influencing factors of groundwater level in the mountain-front alluvial plain of Hutuo River in Shijiazhuang under the influence of human activities, based on the data of precipitation, groundwater level depth, groundwater exploitation, population and GDP in the study area, the average groundwater level variation map and groundwater flow field of different stages are drawn, and the temporal and spatial evolution characteristics of groundwater flow field are discussed. On this basis, the mechanisms by which human activities (groundwater extraction, artificial governance), natural factors (precipitation) and other factors (population, GDP, land-use type) influence the dynamics of the groundwater level are fully analised. The results show that: 1) On the time scale, the buried depth of groundwater level in the study area increases slowly from 1980 to 2000, increases rapidly from 2000 to 2015, and decreases from 2015 to 2021, and 2016 is the turning point. 2) Groundwater funnel area in Shijiazhuang urban area is large from 1980 to 2015, and groundwater confluence occurs in the funnel area. After 2015, groundwater funnel area in the study area gradually decreases and the confluence gradually disappears. 3) Precipitation and agricultural exploitation of groundwater are the dominant factors in the change of groundwater table from 1980 to 2000, industrial exploitation of groundwater is the dominant factor from 2000 to 2015, and artificial governance is the dominant factor from 2015 to 2021. 4) Population, GDP and land use types indirectly affect the groundwater depth in the study area, and the variation of groundwater depth in the mountain-front alluvial plain of Hutuo River in Shijiazhuang has obvious stage characteristics.
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Evolution of the Proto-Tethys Ocean in Hainan Island: Evidence from Zircon U-Pb Geochronology and Hf Isotopic Compositions of Andesite

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Du Yujing, Zhou Yun, Liu Xijun, , Cai Yongfeng, , Song Hongxing, Zhao Yongshan
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1483-1498.   DOI: 10.13278/j.cnki.jjuese.20210399
Abstract1683)      PDF(pc) (13892KB)(76)       Save

Hainan Island is located at the intersection of Pacific, Indo-Australian and Eurasian plates. It is an ideal location to reveal the tectonic evolution of plate tectonics. In order to gain a better understanding of the Early Paleozoic tectonic evolution of the island, systematic zircon U-Pb geochronological and Hf isotopic analyses of the andesite from the northwestern Hainan Island have been carried out. The results of zircon U-Pb dating show that two representative andesite samples yield ages of LA-ICP-MS(448±5) Ma and (447±11) Ma, respectively. This suggests that Early Paleozoic (Late Ordovician) magmatism occurred on the Island. In-situ zircon Hf isotopic results show that the εHf(t) values of the andesites are -16.48-5.22 and their two-stage model ages (TDM2) are 2 030-953 Ma. Combined with regional geological data, it is evident that the andesites were produced by mixture of mafic and felsic magmas, and their formation is related to the subduction of the Proto-Tethys Oceanic crust.


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Thermal-Hydrodynamic-Mechanical (THM) Coupling Simulation of Enhanced Geothermal System Development in Matouying Uplift Area, Hebei Province
Feng Bo, Cao Yunlong, Qi Xiaofei, Cui Zhenpeng, Zhang Lanxin
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1892-1906.   DOI: 10.13278/j.cnki.jjuese.20230230
Abstract1681)      PDF(pc) (9917KB)(68)       Save
In the long-term mining process of the fractured thermal reservoir of the enhanced geothermal system (EGS), due to the constant extraction of heat from the high-temperature dry hot rock mass, the temperature of the high-temperature granite mass drops, which induces the secondary fracture of the rock mass, and even the occurrence of fluid short circuit reduces the mining efficiency of the geothermal system. In order to ensure the stable extraction of EGS heat energy, it is necessary to establish the coupling model of fluid-solid heat transfer, hydrodynamic and fracture deformation in the test site, and analyze the influence of hydrodynamic and thermal effects on the fracture development law of the reservoir. Based on the test data of circulating water injection at the EGS development site in Matouying Bulge area, Hebei Province, this paper established a coupling model of thermo-hydro-mechanical (THM) of microfractures in the site. The accuracy of the THM coupling model was verified by comparing the model simulation results with the field observation results. The increase of permeability of EGS reservoir and the spatial range of stimulation zone reveal that the range of stimulation zone of reservoir fracture is affected by temperature, pressure and injection flow. The results show that increasing the water injection pressure can stimulate the shear fracture of existing fractures and broaden the area of stimulation zone. Reducing the temperature of water injection can improve the permeability of fluid and expand the reservoir stimulation zone. In the initial stage of hydraulic fracturing, the proper use of cold water injection is conducive to improving the reservoir permeability, and increasing the injection flow will expand the range of reservoir stimulation zone.
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Geological and Geochemical Characteristics and Forming Environments of Siliceous Rocks in the Bangong Lake Ophiolite Mélange, Tibet
Liu Demin, Chen Liang, Zhang Li, Lu Wanling, Liu Fei, Qi Yanya, Jiang Huai, Zhao Yue, Zhang Xiaobo, Ru Jiangtao
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1722-1733.   DOI: 10.13278/j.cnki.jjuese.20230165
Abstract1680)      PDF(pc) (29134KB)(55)       Save
 The ophiolite mélange is an ideal laboratory for studying the process of ocean-continent transition and plate tectonics to intracontinental tectonic transition. In this paper, the petrology and geochemical characteristics of major and rare earth elements of siliceous rocks were studied to judge the origin and forming environment of Bangong Lake ophiolite mélange in Tibet. The siliceous rocks occur as intercalated beds in Shamuluo Formation or fault-fragments in basalt, exhibit cryptocrystalline texture, bioclastic texture and massive structure, and contain abundant Late Jurassic-Early Cretaceous radiolarite. They have a SiO2 content of 73.80% to 90.44%,  and a high Al2O3 content of 3.67% to 12.33%. The ratios of MnO/TiO2, Fe2O3/SiO2, Fe2O3/TiO2, and Al2O3/(Al2O3+Fe2O3) range from 0.14 to 0.91, 31.44 to 141.88, 1.83 to 11.80, and 0.66 to 0.96, respectively. After standardization of rare earth elements in North American shale, it shows a flat rare earth distribution pattern, with Ce showing a negative anomaly overall and Eu showing a weak positive anomaly overall; δCe values is 0.77 to 2.03, δEu value is 0.99 to 2.11. The values of (La/Yb) N, (La/Ce) N, (La/Lu) N, (La/Sm) N, (Ce/Yb) N, and (Gd/Lu) N are 0.43 to 1.12, 0.51 to 1.27, 0.44 to 1.26, 0.59 to 1.12, 0.41 to 2.01, and 0.82 to 1.16, respectively. After standardization, the rare earth element chondrite shows a right-leaning rare earth distribution pattern, with overall Ce showing weak positive anomalies and overall Eu showing negative anomalies. The authors propose that the formation environment of the siliceous rocks is not a typical continental margin, but rather a certain distance from the continental margin between ocean basin and continental margin. In combination with the results of area studies, the formation environment of the Bangong Lake ophiolite mélange is preliminarily identified as a back arc ocean basin environment, which is the product of the northward subduction of the Bangong Lake-Nujiang Ocean basin in the Late Jurassic. 
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Geochemical Tracing and Discrimination of Paleosedimentary Environment of Sedimentary Rock Intercalation During Volcanic Eruption Intervals

Zhang Huan, Chen Yajun, Wu Hongmei, Ma Qiang
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1417-1436.   DOI: 10.13278/j.cnki.jjuese.20210289
Abstract1676)      PDF(pc) (24755KB)(54)       Save

The paleosedimentary environment during the preservation of volcanic materials is one of the key factors influencing the volcanic oil-gas reservoir. During the interval of volcanic eruption, the deposited thin sedimentary lithologic layer has sedimentary characteristics. The trace elemental characteristics in the thin sedimentary layers are closed related to the paleosedimentary oxide-reductive environment and are important parameters for paleoenvironment identification. Thus, the paleosedimentary environment can be identified indirectly based on the trace element analysis on cores of the thin sedimentary layers during volcanic eruption intervals. Thin sedimentary lithologic layers, including mudstone and siltstone, had deposited during the interval of volcanic eruption in the Upper Carboniferous Haerjiawu Formation of Malang sag, Santanghu basin, Xinjiang. Eleven types of trace element ratios of these fine sediments, including U/Th, authigenic U, V/Cr, Ni/Co, V/Sc, V/(V+Ni), Cu/Zn, Fe3+/Fe2+, Sr/Ba, V/Zr, and B/Ga are used to trace the oxide-reductive paleoenvironment during the interval of volcanic eruption. Seven kinds of parameters, V/(V+Ni), V/Sc, Sr/Ba, V/Cr, V/Zr, Cu/Zn and B/Ga of mudstone, carbon mudstone, and siltstone indicate an underwater reduction environment and the coastal shallow sea environment with frequent water-land transition; It is concluded that the volcanic rocks of the Haerjiawu Formation are mainly deposited by eruption and preserved in underwater environment, and the complex sedimentary genetic environment of frequent water-land transition also exists.

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Numerical Simulation of Exploitation and Reinjection of CarbonateGeothermal Reservoir in Rongcheng Geothermal Field, Xiongan New Area

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Ma Feng, Gao Jun, Wang Guiling, Liu Guihong, Yu Mingxiao, Zhao Zhihong, Liu Jinxia
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1534-1548.   DOI: 10.13278/j.cnki.jjuese.20220004
Abstract1663)      PDF(pc) (16653KB)(86)       Save

The balance of exploitation and reinjection is an effective model for the sustainable development and utilization of hydrothermal geothermal resources. In order to simulate the temperature and pressure response of geothermal reservoir under different exploitation and reinjection scenarios, and to provide theoretical support for the sustainable development of geothermal resources, a mathematical model of Jixian system carbonate geothermal reservoir in Rongcheng geothermal field in Xiongan New Area was established by using numerical simulation technology. Firstly, COMSOL software was used to simulate the exploitation history data of existing geothermal wells in 300 km2 area. The simulation results are in good agreement with the monitoring data. Then, on this basis,the variation trends of temperature and pressure field of Jixian geothermal reservoir in the future 50 years under the single well exploitation model were predicted. Finally, according to the the declining trend of water level, the reinjection scheme was established, and the influence degree of different well spacing on the temperature field and pressure field of geothermal reservoir was analyzed. The results show that in the non-reinjection mode, the buried depth of water level decreases to 150 m in about 40 a, and the water level decreases about 1.13 m/a. The geothermal doublet system of  “one exploitation and one reinjection” scheme is adopted, and the well spacing is considered to be 600, 800 and 1 000 m respectively. Although increasing the well spacing reduces the number of arranged wells, it increases the exploitation amount and prolongs the thermal breakthrough time, so that more heat can be exploited. In practical engineering, the well spacing should be optimized by numerical simulation method to ensure the increase of production and prolong the thermal breakthrough time, so as to extract more heat.


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Genesis of Tuanjiegou Epithermal Gold Deposit in Heilongjiang Province: Evidence from Zircon U-Pb Dating, Element Geochemistry and Hf-S-Pb-He Isotopes
He Juncheng, Liu Jun, Li Xiaowei, Wang Xiaotong, Sun Peng
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1437-1466.   DOI: 10.13278/j.cnki.jjuese.20210387
Abstract1649)      PDF(pc) (33639KB)(101)       Save

The Tuanjiegou deposit, located in Jiayin County, Heilongjiang Province, is the largest epithermal gold deposit in Northeast China. This study systematically investigated the petrography, zircon U-Pb dating, whole-rock major and trace elements, LA-ICP-MS zircon in-situ trace elements and Hf isotopes of granodiorite porphyry and granite porphyry. Additionally, single mineral Pb-He isotope and LA-ICP-MS in-situ S isotope analyses of gold-bearing pyrite were conducted. The zircon U-Pb ages of granodiorite porphyry and granite porphyry are (105.9±1.1) Ma and (102.3±1.2) Ma, respectively, belonging to calc-alkaline to high-K calc-alkaline series. These rocks are enriched in light rare earth elements and large ion lithophile elements such as Rb and K, but depleted in P, Ti, Nb, Ta and other high field strength elements. The Ce4+/Ce3+ values of zircons in granodiorite porphyry range from 165 to 656 ℃ (mean 322 ℃), with Ti saturation temperatures ranging from 605 to 715 ℃ (mean 658 ℃). On the other hand, the Ce4+/Ce3+ values of zircons in granite porphyry range from 359 to 868 (mean 480), with Ti saturation temperatures ranging from 606 to 680 ℃ (mean 646 ℃). Zircon εHf (t) values of these two rocks are 6.9-8.1 and 5.6-8.2, respectively. The δ34S value of pyrite ranges from -7.8‰ to -0.2‰ with an average of -3.5‰, and the common Pb isotope ratios are 206Pb/204Pb=18.160-18.399, 207Pb/204Pb=15.538-15.590, and 208Pb/204Pb=38.135-38.340. The R/Ra values of fluid inclusions in pyrite range from 0.75 to 1.23. Comprehensive characteristics suggest that the mineralization-related magma is derived from the evolution of homologous crystalline magma, and the of magma emplacement occurred during the Early Cretaceous. The initial magma may have originated from the partial melting of the young lower crust material during the subduction of the Paleo-Pacific plate, with some mantle-derived materials mixed in during the formation process. The ore-forming fluid comes from deep magma and exhibits the characteristics of a mixed crust-mantle source (with the crust being the main source and mantle fluid accounting for 8.23% to 13.62%). The higher oxygen fugidity and lower magmatic crystallization temperature of granite porphyry provide favorable conditions for gold accumulation and migration, thus facilitating large-scale gold mineralization.


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Prediction of Greenhouse Gas N2O Emission Reduction Potential in Farmland of Jilin Province
Zhao Yuyan, Yu Qianqing, Tang Xiaodan, Song Meitong, Li Bing
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1917-1927.   DOI: 10.13278/j.cnki.jjuese.20230269
Abstract1647)      PDF(pc) (4730KB)(104)       Save
 N2O is an important greenhouse gas, and farmland is considered to be one of the major sources of its emission. Exploring the reduction potential of N2O not only provides theoretical and technical support for farmland carbon emission reduction measures, but also provides a scientific basis for the realization of China's "double carbon" goal. In order to reduce N2O emissions in Jilin Province, the denitrification-decomposition (DNDC) model was used for point simulation, result verification and sensitivity analysis based on the data of greenhouse gas emissions from Jilin University Functional Agriculture Base (Hunchun). At the same time, the N2O emissions were simulated from 1991 to 2020 under the conditions of corn planting in Jilin Province, its temporal and spatial characteristics were obtained, and the optimization measures for increasing corn production and reducing N2O emissions were proposed. The result shows that the DNDC model was effective in the simulation of N2O emissions from farmland in Jilin Province. Among all the  factors,  nitrogen fertilizer application rate had the greatest influence on N2O emission, followed by  organic fertilizer application rate, soil organic carbon content  also had a certain infulence on N2O emission,while temperature, rainfall and  proportion of straw returning to field had little influcence on N2O emission. As a result of corn cultivation, N2O emissions are highest in the west, middle in the central region and lowest in the east. In order to reasonably control N2O emissions from farmland in Jilin Province, different field management should be carried out in different regions, and the optimal nitrogen application rates are 400, 330 and 480 kg/hm2 with the best base to topdressing application ratios of 7∶3, 9∶1 and 9∶1 in the west, central and east, respectively. The proportion of straw returned to the field has little effect on N2O emissions. While maintaining production, reducing the mass fraction of organic carbon can decrease N2O emissions from agricultural land.
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Triaxial Shear Behavior of Saturated Remolded Loess Subjected to Five Drainage Conditions
Liu Xin, Miao Xueqing, Huang Liang, Wei Xiao
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1499-1509.   DOI: 10.13278/j.cnki.jjuese.20220231
Abstract1640)      PDF(pc) (5517KB)(118)       Save

 In order to explore the drainage status and the associated impact of loess in engineering practice, strain increment ratio by triaxial test are used to investigate the shear behavior of saturated remolded loess subjected to five drainage conditions, which are no drainage condition, forced water absorption condition, free drainage condition, forced drainage condition, and partial drainage condition. The results show that, the shear behavior of saturated remolded loess are closely related to drainage conditions. In no drainage condition and forced water absorption condition, the loess samples exhibit strain softening behavior. Taken broadly, under the condition of forced water absorption, the shear expansion of the sample is forcibly exerted. In free drainage condition and forced drainage condition, the loess samples exhibit a strain hardening behavior, and the dilatancy is inhibited in the imposed drained samples. In partial drainage condition, the loess samples show a strain softening behavior or a transition state from strain softening to hardening, in which it is not only related to the strain increment ratio, but also to the void ratio. The closer the strain increment ratio is to 0, the more obvious the softening degree of the sample is. While the smaller the pore ratio of the sample, the more obvious the shear expansion trend is in the initial shear stage, and the higher the peak strength and residual strength of the sample. Besides, based on the asymptotic state equation and the stress-dilatancy relationship, the asymptotic behavior of loess and the associated dilatancy are analyzed. The result shows that the stress ratio of remolded loess at asymptotic state is negatively correlated with the sample dilatancy. 


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Geophysical Exploration and Application of Underground Brine of Mahai Salt Lake in Qaidam Basin
Zhao Quansheng, Kong Zhihan, Hu Shuya, Zhang Jianwei
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1560-1572.   DOI: 10.13278/j.cnki.jjuese.20220073
Abstract1638)      PDF(pc) (25429KB)(24)       Save

The salt lake area of the Qaidam basin has abundant reserves of underground brine resources, the regional brine reservoirs have the characteristics of lower porosity, strong heterogeneity and anisotropy, and large differences in regional brine-rich properties. In order to accurately detect the underground brine enrichment area and determine variation range of salt rock distribution density difference of the Mahai Salt Lake, it is aimed at the unique salt rock medium, the high salinity of intercrystalline brine, and the coexistence of various brine storage modes such as pore brine storage and structural brine control in the salt lake area of the Qaidam basin. The multi-scale and multi-geophysical exploration method including pumping test, high-precision gravity method, audio magnetotelluric method and high-resolution seismic method were used to detect the distribution density difference variation range of salt rock layer, the electrical change of crystalline salt layer and brine-rich stratum. The pumping test shows that the brine enrichment area composed of Wells K12, K13, K14 etc. has a water yield of 37 297 m3/d in brine rich area Ⅰ. The brine enrichment area composed of T1, K1, K4 etc. has a water yield of 35 736 m3/d in brine rich area Ⅱ. Based on pumping test and integration technology of various geophysical exploration information, two underground brine enrichment areas that can be sustainably and stably exploitated were determined, stratigraphic structure and geological structure in the Mahai Salt Lake were delineated and established.


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Development Prospect Analysis of Cambrian-Ordovician Karst Geothermal Reservoir in Chengning Uplift Area, Shandong Province
Feng Bo, Liu Xiyao, Wang Xuepeng, Feng Shoutao, Liu Shuai, Cui Zhenpeng
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1521-1533.   DOI: 10.13278/j.cnki.jjuese.20220057
Abstract1637)      PDF(pc) (10129KB)(42)       Save

To further explore the geothermal storage resources in the Chengning uplift region of Shandong, it is necessary to make reasonable and sustainable development plans to provide scientific basis for further exploration and comprehensive development of geothermal resources . In this paper, the geological survey data and field test results are used to analyze the genesis of geothermal fluids. Using the thermal storage method and comprehensive index method to estimate the resource quantity and analyze the development prospects of the Cambrian-Ordovician karst geothermal resources and provide scientific basis for further exploration. The result shows that the available geothermal resources of Cambrian-Ordovician karst heat reservoir are 1.97×1019 J, equivalent to 6.72×108 t of standard coal; The annual recoverable amount of geothermal fluid is 29 777.40×104 m3 /a. The area available  for development is 1 538.29 km2, accounting for 86.18% of the total karst geothermal area. The Cambrian-Ordovician karst geothermal reservoirs in the area have great potential for development and utilization, so that exploration efforts should be increased to promote the development and utilization process.

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Sepiolite Modified Soil-Bentonite Slurry Barrier Wall Cut-off Heavy Metal Cation Pollution in Groundwater

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Zhao Yongsheng, , Dai Zhenwei
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1549-1559.   DOI: 10.13278/j.cnki.jjuese.20210401
Abstract1633)      PDF(pc) (7620KB)(82)       Save

In order to investigate the effect of sepiolite addition on the construction workability and permeability of soil-bentonite slurry barrier wall, as well as the retardance of heavy metal cation contamination in groundwater, natural sepiolite was used to modify the soil-bentonite slurry barrier wall. Lead was used as a representative contaminant and slump, permeability and adsorption tests were carried out. The results show that the addition of sepiolite not has much impact on the construction workability of the soil-bentonite-sepiolite barrier material. Increasing the sepiolite dosage from 0 to 30% increases the optimum water content of the barrier material by only 1% when meeting the target slump requirement. Sepiolite has little effect on the permeability performance of the slurry barrier material in the experimental dosage range, and the permeability coefficients of the materials are less than 10-7 cm/s, which can meet the engineering requirements. The adsorption of Pb2+ by the soil-bentonite-sepiolite material is an adsorption process dominated by chemical adsorption, and the adsorption amount of Pb2+ by the material was 89.73, 112.52, 140.85, 183.40 mg/g in the order of 0, 5%, 10%, and 20% of sepiolite doping, and the adsorption amount was reduced when the temperature was decreased. Under the corrosion of Pb2+, the permeability coefficient of the soil-bentonite-sepiolite barrier material gradually increases, but the presence of sepiolite can delay the corrosion of Pb2+ to the barrier material. Changes in pH and lead mass concentration of the exudate indicate that the soil-bentonite-sepiolite barrier material still acts as a blocking material during the experimental time.


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 Classification and Model of Volcanic Facies in the Basin
Tang Huafeng, Bian Weihua, Wang Pujun, Gao Youfeng, Huang Yulong, Zhang Yan, Hu Jingsong
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1651-1671.   DOI: 10.13278/j.cnki.jjuese.20230256
Abstract1622)      PDF(pc) (19422KB)(165)       Save
 Volcanic facies model in the basin is an important basis for reservoir distribution and identification. There are still some problems including stratigraphic unit inconsistency, unsystematic drilling, and large differences between basins. It is necessary to establish a system of facies models of basic stratigraphic units. This paper summarizes the definitions of facies, lithofacies and volcanic facies. Volcanic facies are divided into three classification schemes, which are for geological mapping and mineral survey in field, modern volcanoes and volcanic rocks in basin. It is considered that it is preferancial to apply the modern volcanic research results to guide the study of volcanic facies in the basin. The deposited units of volcanostratigraphy highlight the elements of rock fabric and geometric shape, and the volcanic facies division scheme of 5 facies, 15 subfacies and 44 microfacies is summarized. The eruptive facies is divided into pyroclastic flow, base surge, volcaniclastic apron, and volcaniclastic diatreme subfacies. The effusive facies is divided into subaerial lava flow, subaqueous lava flow, and subaerial eruption-subaqueous emplacement lava flow subfacies. The extrusive facies is divided into subaerial lava dome, underwater lava dome, and early subaqueous-late subaerial lava dome subfacies. The volcano-sedimentary facies is divided into lahar and debris avalanche subfacies. The subvolcanic facies is divided into dikes, laccolith and sill/lopolith subfacies. The characteristics of the fabric and structure of each microfacies are pointed out. Lava with different chemical compositions can form the same subfacies or microfacies. For example, rhyolite and basalt can both form the braided lava flow subfacies of the subaerial lava flow, while rhyolite, dacite, andesite, and basalt can all form the subaerial lava dome. With respect to the reservoir potential, the braided lava flow microfacies is better than the various microfacies of the subaerial lava dome. Therefore, the classification scheme in this paper can establish a detailed correlation between the subfacies/microfacies and the reservoir, and can be suitable for reservoir prediction and volcanic facies comparison in the basin.
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Shale Lithofacies and Gas-Bearing Characteristics of the Lower Paleozoic Wufeng Formation-Member 1 of Longmaxi Formation in Changning Area, Southern Sichuan
Shan Xuanlong, Xing Jian, Su Siyuan, Li Ang, Zhao Zhenduo, Yang Qin, Li Xuesong, Jing Cui, Zhang Jiahao, Sun Yue
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1323-1337.   DOI: 10.13278/j.cnki.jjuese.20210386
Abstract1618)      PDF(pc) (19492KB)(106)       Save

 The study of shale lithofacies is the basic work of shale gas geological evaluation and layer selection. This paper takes the Wufeng Formation-Member 1 of Longmaxi Formation in Changning area of Sichuan basin as the research object. By using outcrop, drilling, and logging data, combined with rock and mineral, thin section, and geochemical data, the mineral composition, lithofacies characteristics, and their influence on gas content of shale are systematically studied, the favorable lithofacies are determined, and the spatial distribution characteristics of shale lithofacies in Changning area are characterized. The results show that there are five lithofacies in this area: Clay-siliceous mixed shale, mixed shale, siliceous shale, calcareous-siliceous mixed shale, and calcareous shale. Vertically, the volume fraction of carbonate minerals gradually decreases from bottom to top, and the integral number of clay minerals gradually increases. The lithofacies is a transition of calcareous siliceous shale-siliceous shale-clay-siliceous mixed shale. The subsidence center of the study area is located in the northeast of Changning area, and the lateral thickness of the siliceous shale lithofacies shows an increasing trend from southwest to northeast. The siliceous shale has the characteristics of high biogenic siliceous mass fraction, high w(TOC), high brittleness, and high pore structure parameters, so it has the best gas content. Although the clay minerals in the clay-siliceous mixed shale can generate secondary pores through diagenetic transformation, their plasticity is high, and the pores are difficult to preserve due to compaction. In addition, the higher plasticity leads to undeveloped shale fractures, which further reduces the physical properties of the reservoir, and the clay-siliceous mixed shale has poor gas-bearing properties.

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Research Develpment of Airborne Gravity (Magnetic) Multi-Components Gradient Detection and Inversion Technology
Ma Guoqing, Wang Junnan, Meng Qingfa, Meng Zhaohai , Qin Pengbo, Wang Taihan, Li Lili
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1928-1949.   DOI: 10.13278/j.cnki.jjuese.20230246
Abstract1616)      PDF(pc) (14993KB)(108)       Save
Airborne gravity magnetic gradient and tensor gradient measurements can effectively reduce the impact of environmental noise, describe the distribution of geological bodies, and highlight shallow geological bodies with higher resolution. With the develpment of measurement equipment, it has been applied in oil, gas, and mineral resource exploration. This article systematically summarizes the research progress of airborne gravity (magnetic) multi-components gradient detection technology, providing a reference for subsequent related research. The progress development of equipment at home and abroad is summarized based on the research background of airborne gravity and magnetic multi-components gradient technology. The data processing process is introduced based on the characteristics of multi parameter gradient data in airborne gravity and magnetism. Obtained from the airborne gravity and magnetic multi-components gradients’resolution characteristics, we summarize the current high-resolution inversion and joint inversion methods for gravity and magnetic multi-parameter gradients. Derived from the application characteristics of airborne gravity and magnetic multi-components gradient detection technology in mineral,oil and gas resource exploration, the application prospects of this technology in deep resource exploration are analyzed, such as identifying underground structures, searching for mineral resources, and detecting small underground target bodies.
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 Research Status and Prospect of Deep Driving Mechanism of Co-Occurrence of Geothermal Resources and Seismic Activity
Han Jiangtao, Niu Pu, Liu Lijia, Wu Yihao, Xin Zhonghua, Li Zhuoyang, Jia Xiaodong
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1950-1968.   DOI: 10.13278/j.cnki.jjuese.20230247
Abstract1614)      PDF(pc) (25068KB)(143)       Save
 The geological processes and their interactions in the earth not only control the formation and evolution of global geological patterns, but also control the formation of geothermal resources and the occurrence of seismic activities. Through systematic investigation and summary, this paper systematically discusses the symbiotic deep driving mechanism of geothermal resources and seismic activities. Firstly, the background of the formation of global high-temperature geothermal and large/ultra-large seismic zones are summarized. Most high-temperature geothermal and large earthquakes overlap in spatial distribution and are formed  at  active plate margins, while medium-low-temperature geothermal is often formed in  plates and accompanied by seismic activities. Secondly, the deep driving factors of the symbiosis between geothermal resources and seismic activity are summarized, and it is found that fluid and fault structure play a crucial role in the release of heat energy and earthquake, and are the main controlling factors of geothermal resources and seismic activity in deep depth. Thirdly , the results of deep geophysical exploration of geothermal resources and seismic activity are summarized, indicating that the homology and causality relationship between geothermal and earthquake can be revealed by magnetotelluric methods, and geothermal and earthquake are derived from the exchange of deep matter and energy. Finally, the research methods and development direction of the deep driving mechanism of the co-occurrence of geothermal resources and seismic activities are prospected.
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Research Progress on Seismic Exploration Methods and Technologies for Metal Mines
Zhang Pan, Han Liguo, Gong Xiangbo, Zhang Fengjiao, Xu Zhuo
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1969-1982.   DOI: 10.13278/j.cnki.jjuese.20230275
Abstract1598)      PDF(pc) (7133KB)(226)       Save
 Seismic exploration technology has the characteristics of large penetration depth and high resolution and is an essential geophysical technical means to achieve the goal of exploring deep mineral resources in China. Compared with non-seismic geophysical exploration methods, seismic exploration methods provide intuitive and straightforward structural imaging, providing powerful guidance for identifying magma migration channels and finding favorable mineralization spaces. At the same time, it can also explore hidden ore bodies in-depth and find mineralization parent materials. It thus can provide strong technical support for developing and utilizing deep mineral resources. This paper reviews the technological development of active source and passive source seismic exploration methods for metal deposits, respectively, and points out the technical advantages and progress of active and passive source joint exploration methods. Multi-source joint seismic exploration method and technology based on active and passive source data fusion, seismic data processing and interpretation method and technology based on scattering theory, high-precision signal-to-noise separation technology, and metal mine seismic exploration method and technology based on artificial intelligence are the key and potential methods to solve the problems of high-precision and high-resolution detection of deep metal mineral resources.
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Effect of Water-Rock Interactions on the Deterioration of Filled Jointed Rock
Chai Shaobo , Song Lang, Zhou Wei, Fu Xiaodong, Zhou Yongqiang
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1510-1520.   DOI: 10.13278/j.cnki.jjuese.20220050
Abstract1598)      PDF(pc) (7415KB)(120)       Save

In order to compare the effects of different water-rock interactions on the damage and deterioration of filled jointed rock. The longitudinal wave velocity test, static uniaxial compression test and dynamic impact test are carried out on the filled jointed rock under the conditions of dry-wet cycle and continuous immersion. The effects of two different water-rock interactions on the wave velocity value, static and dynamic compressive strength,energy dissipation characteristics of filled jointed rocks are analyzed. Furthermore, the differences are compared in the degradation effects of mechanical parameters of filled jointed rock under different states (dry and water containing) after dry-wet cycle. The results show that, when the number of water-rock interactions is less than 10, the wave velocity of the rock sample under dry-wet cycle is significantly lower than that under continuous immersion. Howerver, with the increase of the water-rock interaction times, the difference in wave velocity values between the two cases is constantly narrowing. With the increase of the number of water-rock interactions, the static compressive strength, dynamic compressive strength and energy dissipation rate of the filled jointed rock decrease. Under 20 dry-wet cycles and continuous immersion, the static compressive strength of filled jointed rock decreased by 27.16% and 18.94%, the dynamic compressive strength decreased by 23.33% and 21.76%, and the energy dissipation rate decreased by 74.29% and 59.71%, respectively. It can be seen that the damage and deterioration of the filled jointed rock caused by the dry-wet cycles is greater than that caused by continuous immersion. In addition, the static compressive strength of the dry state rock sample is higher than that of the water-containing state rock sample after the action of dry-wet cycle, while the dynamic compressive strength of the dry state rock sample is lower than that of the water-containing state rock sample.


1. School of Civil Engineering,Chang’an University,Xi’an 710064,China

2. School of Civil Engineering,Hunan City University,Yiyang 413000,Hunan,China

3. Institute of Rock and Soil Mechanics, Chinese Academy of Sciences,Wuhan 430071,China

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Study on the Evolution of Pore Structure Characteristics of Xinjiang Oil Shale During the Heating Progress
Zhang Wen, Lan Sheng, Ma Wenliang, Wang Jia
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1689-1705.   DOI: 10.13278/j.cnki.jjuese.20230033
Abstract1597)      PDF(pc) (13517KB)(114)       Save
Pore structure is an important feature of oil shale, which directly affects the storage and transport of shale oil and gas. Therefore, studying the evolution of pore structure is of great significance to guide the in-situ exploitation of oil shale. In this paper, taking Balikun oil shale as the research object, based on thermogravimetric (TG), low-temperature nitrogen adsorption (LTNA) and mercury intrusion porosimetry (MIP) tests, combined with LTNA-MIP joint accurate characterization methods, to reveal the law of pyrolysis weight loss and pore development characteristics of Balikun oil shale during heating, and study the evolution process and mechanism of pore structure. The results show that the thermal weight of Xinjiang oil shale can be divided into low temperature slow weight loss section (20-360  ℃), medium temperature rapid weight loss section (360-500  ℃), and high temperature slow weight loss section (500-600  ℃). The internal pore types of Balikun oil shale are complex, and during the heating process, the micro and small pores evolve from slit type to conduit shape. The medium and large holes are always mainly inkbottle-shaped. The inkbottle-shaped pores developed intensively in the two temperature ranges of 300-400  ℃ and 500-600  ℃, and the effective pores developed in large quantities at 400-500  ℃. Native macropores dominated the low-temperature section, and the pore structure changed little under the combined influence of free water vapor pressure, mineral thermal expansion, and asphaltene softening. The concentrated pyrolysis of organic matter in the middle temperature section produces a pore expansion effect, the pore volume is significantly increased, and the pore type is mainly mesoporous. The expansion pressure is generated by the water loss of clay minerals and the phase change of quartz in the high temperature section, and the large pores and middle pores are further expanded.
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 Multiple Weighted HVSR Method Based on XGBoost
Han Fuxing, Song Bingxuan, Chen Yubei, Wu Linjun, Huang Mengting, Pan Yanjie
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1983-1990.   DOI: 10.13278/j.cnki.jjuese.20230268
Abstract1586)      PDF(pc) (4763KB)(78)       Save
 Applying the microtremer H/V method in urban areas faces many complex artificial noises. The microtremer data with a large number of noise needs to be denoised and extracted. In this paper, a   multiple weighted HVSR method based on XGBoost (extreme gradient boosting) is proposed to solve the problems that the existing methods are difficult to deal with the microtremer data with considerable interference and the signal extraction process is cumbersome. Firstly, the amplitude and frequency of the microtremer data are analyzed.  Amplitude-weighted spectral ratio, frequency-weighted spectral ratio, and multiple weighted spectral ratio are established. Then, the denoised HVSR curve is calculated by the XGBoost method. The proposed method is compared with the STA/LTA (short-time average/long-time average) method  to analyze the actual high-noise data, the results show that the proposed  method is better than the STA/LTA method for high-noise data extraction. 
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 Review on Research Progress of Recovering Bathymetry from Satellite Altimetry-Derived Data
Jiang Tao, Jiang Xiao , Guo Jinyun, Zhang Zhonghui
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 2029-2044.   DOI: 10.13278/j.cnki.jjuese.20230285
Abstract1586)      PDF(pc) (11078KB)(88)       Save
 High-precision, high-resolution global seafloor topography models are critical foundational datasets for studying the Earth’s shape and interior structure. They are significant in multiple domains, including seafloor plate movement research, early tsunami monitoring, deep-sea resource exploration, underwater marine construction projects, ensuring maritime safety, and delineating marine territorial boundaries. The extensive and profound realms of the oceans present a formidable challenge for meticulously mapping the seafloor topography. However, satellite altimetry, with its global coverage, high precision, high resolution, and the ability to conduct regular observations of ocean dynamics, has emerged as the primary method for obtaining global bathymetric data. This paper provides an overview of the current state and recent developments in recovering bathymetry from satellite altimetry-derived data. It encompasses fundamental principles, major modes, and missions in satellite altimetry, marine gravity field inversion, methods for seafloor topography inversion, and seafloor topography model products. Additionally, the paper provides insights into the trends and prospects for constructing high-precision, dynamic global seafloor topography models.
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Palynological Records and Paleoclimatic Characteristics of Nenjiang Formation in Lishu Fault Depression, Songliao Basin
Gao Yuan, Qin Tian, Li Ruihong, Zhou Yeze, Liu Hang, Li Mingjun, Zhu Chunguang, Liu Wantao
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1391-1402.   DOI: 10.13278/j.cnki.jjuese.20220130
Abstract1576)      PDF(pc) (18353KB)(114)       Save

Based on the sporopollen analysis of the strata in the 21.47-38.26 m section of ZK004 borehole in the Lishu fault depression, Songliao basin, and combined with the quantitative analysis results of oxide samples, this stratum is divided into two sporopollen assemblages from bottom to top, of which the ZK004-Ⅰ assemblage is dominated by Classopollis-Cedripites-Schizaeoisporites-Callistopollenites-Borealipollis, reflecting the transition from semi-humid   tropical-subtropical  climate to  humid subtropical climate; the ZK004-Ⅱ assemblage is dominated by Cedripites-Rugubivesiculites-Schizaeoisporites-Deltoidospora-Cyathidites-Borealipollis, reflecting the transition from  humid subtropical climate to semi-humid subtropical climate, which generally displays semi-humid northern subtropical climate, providing new evidence for the recovery of the paleoclimate and paleovegetation of the second member of Nenjiang Formation in the Late Cretaceous.


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Sedimentary Characteristics of Leiolitic Bioherms of Cambrian Zhangxia Formation in Zhucaoying Section, Qinhuangdao, Hebei
Zhu Yidan
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1403-1416.   DOI: 10.13278/j.cnki.jjuese.20220043
Abstract1561)      PDF(pc) (50358KB)(25)       Save

In the forced regressive system at the top of the Cambrian Zhangxia Formation in the Zhucaoying section of Qinhuangdao, Hebei Province, a set of leiolitic bioherms with a thickness of tens of meters were intensively developed, indicating that these leiolitic bioherms formed in shallow sea and high energy environment. Field investigation and microscopic observation, the formation mechanism and sedimentary environment of leiolitic bioherms are analyzed.The results show that the leiolitic bioherms  dense and homogeneous massive micritic limestone,  obvious macro fabric and directly the lower stromatolite bioherms.Under the microscope, the leiolite is composed of dense micrite and a small amount of sparry. The dense micrite contains a variety of calcified cyanobacteria sheath fossils, including Hedstroemia, Epiphyton, Renalcis,   and Girvanella. The results showed that the leiolite was formed by the complex metabolism of microbes and  in-situ. More specifically, oolith and dolomite crystals, indicating that the microtexture related to the calcification of globular microbial film and the selective expression of dolomite in the process of leiolite production under eutrophic conditions. There are not many related examples of leiolite since its, therefore the leiolitic bioherms in Zhangxia Formation of Qinhuangdao provide a typical example for understanding the formation mechanism and depositional environment of leiolite.


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Impregnated Diamond Bit Optimal Design and Application in GanQing Tunnel
Ma Yinlong, Zhang Shiyu, Zhou Fujun, Sun Zhigang, Ren Jie
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1845-1853.   DOI: 10.13278/j.cnki.jjuese.20230292
Abstract1561)      PDF(pc) (4399KB)(16)       Save
The impregnated diamond bit is a micro-cutting edge formed by exposing diamond in the matrix, and realizes the drilling of broken rock by crushing and grinding the rocks under the action of drilling pressure and torque. It can be widely used in hard formation and complex formation drilling. However, conventional diamond drill bits have problems such as low drilling speed, slow footage and high costs in hard formations. Firstly, rock samples, which were sampled in different depths form holes adjacent to the borehole S2Z-45 in GanQing  tunnel, were taken for testing and analysis of their hardness, mineral composition, and drillability. It was determined that most of rock layers were mainly diorite, and the rock’s drillability level was eight. Then, according to the geological characteristics of Ganqing tunnel, the matrix hardness and bottom lip shape of impregnated diamond were optimized. The influencing factors of the performance of impregnated diamond bit was analyzed by field tests. The experimental results showed that the impregnated diamond bit had the best performance when its matrix hardness was HRC 15-20, a diamond particle size was 40-50 mesh, the volume fraction of diamond was 20%, and a bottom lip with a ring groove sharp tooth shape. It has a lifespan of 321 m and a drilling speed of approximately 1.17 m/h. Under the same diamond parameters, the hob type impregnated diamond bit with a matrix hardness of HRC 10-15 had advantages in drilling speed, which the drilling speed of the drill bit could reach 1.44 m/h. The sharp tooth bottom lip surface of the ring groove and high matrix hardness helped to improve the life of the drill bit, while the rolling tooth bottom lip surface and low matrix hardness were beneficial for improving drilling efficiency, but the life of the drill bit was relatively low.
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Micropore Structure and Micro Residual Oil Distribution of Ultra-Low Permeable Reservoir: A Case Study of Chang 4+5 of Baibao Area,Wuqi Oilfield
Xiong Anliang, Cheng Guofeng, Li Dongtao, Ding Weipan, Liu Yuxi, Chen Gang, Yang Lei, Yuan Yaoli, Zhu Yushuang, Liu Linyu
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1338-1351.   DOI: 10.13278/j.cnki.jjuese.20220158
Abstract1559)      PDF(pc) (35842KB)(96)       Save

 The qualitative and quantitative characterization of the microscopic pore structure of the reservoir can benefit the efficient development of the reservoir in the later stage. In this study, the microscopic pore structure of Chang 4+5 ultra-low permeable reservoir was characterized in  Baibao area of Wuqi oilfield by using blue-dye thin section, SEM, high pressure mercury penetration. A local pore structure classification standard of the study area was established. Based on the experimental results, a real sandstone model is built up to evaluate the quality of the pore structure by the oil-water two-phase seepage experiment, and the existence types and causes of the micro residual oil in different pore structures are analyzed through the microscopic visualization of the oil-water displacement experiment. The results show that the combination type of class Ⅰ pore structure is intergranular pore-dissolved pore, oil and water two-phase seepage characteristics are the best, after water flooding, the micro residual oil mainly exists in the form of small contiguous clusters, oil displacement efficiency is 35%; Type Ⅱ pore structure is dissolved pore-residual intergranular pore, oil-water two-phase seepage characteristics is similar to class Ⅰ, water storage capacity and water flooding effect are the best, oil displacement efficiency is 43%, after water flooding, the micro-residual oil mainly exists in cluster and ring form; Class Ⅲ pore structure combination type is intercrystalline pore-dissolved pore, it has the worst physical properties, oil and water have the worst seepage characteristics, oil displacement efficiency is only 21%, after water flooding, the micro residual oil exists in the form of contiguous clusters. The diagenesis and the pore filling content in the study area mainly affect the pore structure development, thus affecting the microscopic residual oil distribution of different pore structures after water flooding.


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Review in the Geophysical Methods for Coalbed Methane Resources in Abandoned Coal Mine
Yu Chuantao, Liu Chunlin, Xue Junjie , Zhang Fuming, Li Yong
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1991-2005.   DOI: 10.13278/j.cnki.jjuese.20230284
Abstract1555)      PDF(pc) (11480KB)(96)       Save
 Coal mining has resulted in large areas of goaf and numerous abandoned mines. There are a large amount of coalbed methane resources in these abandoned mines. Different from conventional coalbed methane resources, the exploration and development of coalbed methane resources in abandoned mines are affected by the distribution of open areas, overburden, surrounding rock conditions, development of fissure zones, and conditions of the roof and floor of coal seams, coal mining methods, groundwater in goaves, etc., and geophysical exploration technology can provide technical support for developing coalbed methane in abandoned mines. This article provides an overview of coal geology in Shanxi and explores the factors contributing to the collapse and water accumulation in goaves. It also examines surrounding rocks and goafs' seismic wave, electrical, induced polarization, and radioactive radon anomalies characteristics. Furthermore, the article introduces various detection methods such as seismic, direct current, controlled source audio-frequency magnetotelluric, transient electromagnetic, induced polarization, radioactive prospecting, microtremor exploration, aviation, and semi-aviation transient electromagnetic methods. It is pointed out that developing and researching new geophysical techniques, establishing a multi-method, multi-dimensional, and multi-space comprehensive goaf detection system, making full use of geophysical big data, and in-depth exploration of artificial intelligence inversion technology can provide valuable information for coalbed methane resources in abandoned mines in my country. It is providing technical support for exploration and development.
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 Retrospect, Exploration, and Innovation:A Review on the Tenth International Conference on Gas Hydrates
Guo Wei, Zhang Pengyu, Zhong Xiuping, Wang Xiaochu, Jia Rui, Chen Chen, Wang Yuan
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1760-1772.   DOI: 10.13278/j.cnki.jjuese.20230216
Abstract1555)      PDF(pc) (2679KB)(185)       Save
 The Tenth International Conference on Gas Hydrates (ICGH10) was held in Singapore on July 9-14, 2023, with over 700 attendees, hosted by the National University of Singapore. ICGH10 received 538 abstracts, including 292 orals and 246 posters. ICGH10 summarized the research progress of gas hydrate in the past six years. This paper reviewed three aspects of them including energy exploration and development, flow assurance and hydrate application technology. As a clean and low-carbon energy source, natural gas hydrate has made many breakthroughs in basic theory and field production engineering, but there is still a certain distance from commercial development and utilization; To achieve efficient transportation of oil and gas pipelines, flow assurance technologies related to hydrate blockage have been widely studied. Many environment-friendly hydrate kinetic and thermodynamic inhibitors have been developed. In addition, hydrate technology is gradually moving from experimental research to commercial application in carbon sequestration, water treatment, and gas storage and transportation. This paper summarized the main content of ICGH10, aiming to introduce the latest international research progresses of gas hydrates.
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 Infulence of Three-Pile Structure with Trefoil-Shaped Distribution on Impact of Debris Flow on Bridge Pier
Wang Changming, Liu Xinlei, Wang Fei
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1773-1784.   DOI: 10.13278/j.cnki.jjuese.20230212
Abstract1553)      PDF(pc) (21033KB)(19)       Save
How to mitigate and eliminate the impact of debris flow on bridge pier is crucial to the safety of bridges. Taking the three-pile unit with trefoil-shaped distribution as the protective structures, a design principle for the size of this structures is proposed considering factors such as the characteristics of debris flow movement and the width of bridge piers. Firstly, an optimal arrangement of piles is obtained by simulating the impacts of block stone on different types of pile group structures. Then the impact of the debris flow with block stone on the bridge pier under pile structure was analyzed by using SPH-FEM method. The results show that the impact force of large stones and debris flow slurry on bridge piers is 3 843 kN, which is much greater than the impact force of debris flow slurry on bridge piers without protection, which is 1 840 kN, and the impact force of debris flow slurry on bridge piers with protection, which is 1 452 kN. The pile layout with a column spacing of 3.0 m and a row spacing of 1.0 m is the most stable. And after the protective structure was set up, the peak impact force of debris flow slurry, peak stress and peak displacement at the pier bottom whent=8.0 s were reduced by about 21.1%, 79.0% and 29.3%, respectively. Therefore the pile group structure has a significant protective effect on bridge piers impacted from debris flow.
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Remote Sensing Identification of Dendrolimus Superans Infestation Based on Knowledge Graph and Random Forest
Wang Mingchang, Ding Wen, Zhao Jingzheng, Wu Linlin, Wang Fengyan, Ji Xue
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 2006-2017.   DOI: 10.13278/j.cnki.jjuese.20230279
Abstract1552)      PDF(pc) (5433KB)(83)       Save
 Large-scale outbreaks of Dendrolimus superans infestation have led to severe losses of forest ecosystems and economies. It is of great significance to identify the area of Dendrolimus superans infestation quickly and accurately. In this study, knowledge graph technology was used to screen the sensitive features related to forest pests, and a random forest model with three different data combinations was constructed by comprehensive use of multi-source data to identify the Dendrolimus superans infestation occurrence area in the study area by remote sensing. The results are as follows: 1) The knowledge graph can be constructed and screened according to the graph construction process. In this study, the characteristics of forest insect pests were established by remote sensing, and the characteristics of Dendrolimus superans infestation in Northeast China were screened by remote sensing. 2) The combination of knowledge graph and remote sensing technology can provide practical features for constructing the pest identification model; 3) Compared with a single data source, the identification effect of Dendrolimus superans infestation based on multi-source data is better. In this study, the overall accuracy and Kappa coefficient of Sentinel-1A, Sentinel-2A and topographic data were 92.78% and 0.876 6, respectively. 
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Seismic Stability of Steep Slope Groups in Typical Canyons of Northern South China Sea
Nian Tingkai, Wang Guodong, Zheng Defeng, Wang Dawei
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1785-1798.   DOI: 10.13278/j.cnki.jjuese.20230270
Abstract1549)      PDF(pc) (18580KB)(17)       Save
The northern continental slope of the South China Sea is a large-scale submarine slope that extends in a belt-like configuration from the southeastern waters of Hainan Island to the southwestern waters of Taiwan Island. Several canyons and numerous steep slopes are located at this area. Due to the complex geological structure and earthquake-prone nature of the area, various geo-hazards such as landslides are active. In particular, due to the large topographic relief and frequently seismic activity, earthquake-induced landslides often occur in the region. So it is important to scientifically assess the seismic stability of large submarine landslides. In this study, a three-dimensional numerical model was developed using Scoops3D and GIS technology to investigate the seismic stability of typical steep slope groups located at canyons in the northern continental slope of the South China Sea. The results show that :Most of the canyon profiles in the study area are in the shape of “U”, and it is inferred that the canyons are type Ⅱ submarine canyon system. Strong seismic action can substantially weaken the stability of submarine slopes located at canyons, in which the regional minimum safety factors of steep slope groups in C1 canyon dramatically decreases to 0.50 while the horizontal seismic coefficient with the increase to 0.40. The seismic-induced destabilization range of the steep slope groups in the western canyon is significantly higher than that in the eastern region, and most of the landslides are concentrated in the valley walls on both sides near the crests of the peaks, while a considerable portion of the landslides are located at the eastern valley walls of the southern section in C1 and C2 canyons, with the overall distribution being a belt-like shape. 
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Diversity and Paleogeographic Distribution of Hemicosmitoid and Glyptocystitoid in  Ordovician Meitan Formation of Guiyang
Li Jiale, Lan Tian, Wang Yue
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1380-1390.   DOI: 10.13278/j.cnki.jjuese.20220017
Abstract1544)      PDF(pc) (21823KB)(96)       Save

Echinoderms is one of the most primitive animal groups, and its evolutionary history is crucial for understanding the origin and early evolution of multicellular animals. In this paper, some echinoderm fossils, collected from the Meitan Formation in Wudang area of Guiyang, are identified as thecal plates of the Glyptocystitoida and Hemicosmitoida in the Rhombifera, belonging to Polycosmites and Macrocystella. We also conduct a study of the Ordovician paleogeographic distribution of the two superfamilies, and find that the presence of Polycosmites and Macrocystella in the Meitan Formation expands the biogeographic distribution of the two genera in Yangtze plate. At the same time, this discovery reveals the diversity of echinoderms in Wudang area, and provides new information on the evolutionary radiation of echinoderms during the Early Ordovician.


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 Differential Diagenetic Evolution of Deep Sandstone Reservoirs and Hydrocarbon Charge: A Case Study from the Lower Jurassic in the Fukang Sag, Junggar Basin
Zhang Zengbao
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1672-1688.   DOI: 10.13278/j.cnki.jjuese.20230043
Abstract1543)      PDF(pc) (14315KB)(52)       Save
 Effective reservoir rocks and their genesis in a heterogeneous petroleum reservoir are a critical geological issue of deep exploration. The Lower Jurassic Sangonghe Formation in the Fukang sag, central Junggar basin has been used as a case study to examine the dynamic relationship between diagenetic evolution and oil chargeing in sandstones, and discuss effective reservoir rocks and their formation using an integrated approach of petrography, SEM, stable carbon and oxygen isotopes, and fluid inclusion analyses. The results show the sandstones in the Sangonghe Formation consist mainly of ductile lithic-rich, very fine-to fine-grained, and medium- to coarse-grained petrofacies. The two defined petrofacies are interbeded, and represent demonstrable differences in diagenetic evolution and oil charge. Ductile lithic-rich, very fine-to fine-grained sandstones had a limited diagenetic process in which compaction and neomorphism of easily deformed, clay-rich lithic grains predominated, resulting in a very rapid loss of porosity during burial. They have become relatively nonporous before the first oil arrival and have never been charged later. By contrast, diagenetic events in the relatively coarser-grained sandstones with less abundant ductile-lithic grains included dissolution and cementation as well as ductile compaction. At least two episodes of oil charge occurred. Diagenesis progressed alternately with oil emplacement. The nonreservoir, ductile lithic-rich, very fine-to fine-grained sandstones can constitute impermeable barrier interbeds embedded in permeable reservoir rocks, probably resulting in heterogeneous oil migration.
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Influenceof Meltwater on CO2 Laser Ice Melting
Zhang Nan, Wang Yingyu, Pavel Talalay, Fan Xiaopeng, Gong Da, Wang Ting, Han Bo, Wei Xianzhe, Bai Hongliang, Wang Liang
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1854-1863.   DOI: 10.13278/j.cnki.jjuese.20230280
Abstract1542)      PDF(pc) (4491KB)(98)       Save
 Laser drilling has the advantages of high energy, high directivity, cleanliness, non-contact cutting drilling, etc. In the process of laser thermal melting through the ice, meltwater has a great impact on the laser penetration efficiency. In order to explore the influence of meltwater on laser penetration efficiency, CO2 laser with higher ice absorption efficiency was selected to conduct fixed-point penetration experiments on ice samples prepared by simulated polar ice cores under different irradiation angles and different laser power. The results show that when the negative incidence Angle is -90°--15°, the penetration velocity is 0.67-2.20 mm/s, which is only 21%-40% of the theoretical velocity, and the aperture reaches 3-5 times of the spot diameter. When the Angle of incidence is 15°-45°, the melt water is removed in time due to gravity, and the penetration velocity is 13.19-36.50 mm/s, which is 2.2-6.5 times of the theoretical velocity.
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Risk Assessment and Zoning of Seawater Intrusion Hazard in Coastal Region of Laizhou City Based on AHP-EWM Method
Shu Longcang, Huang Lei, Chen Huawei, Lu Chengpeng, Liu Bo
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1864-1879.   DOI: 10.13278/j.cnki.jjuese.20230047
Abstract1535)      PDF(pc) (6305KB)(98)       Save
Based on the chain transfer process of seawater intrusion hazard, this study established a risk assessment index system of coastal region in Laizhou City according to the risk of disaster causing factors, vulnerability of disaster bearing body, disaster loss and disaster prevention and mitigation capability and ascertained the weight of each index by combined method of the analytic hierarchy process (AHP) and the entropy weight method (EWM) based on the minimum information entropy, ultimately the total risk value and corresponding ranking were obtained by the comprehensive weighted evaluation method to figure the hazard degree and influencing factors of seawater intrusion in Laizhou City. The calculation result of the total risk index showed that Chenggang Road had the highest risk, with a value of 5.76, and Jincang Street had the lowest risk, with a value of 4.03. According to the total risk value, research zone was divided into the highest risk, high risk and lower risk zone. Pearson correlation test and comparison of risk value of indexes presented that groundwater exploitation intensity with correlation index of 0.917 is the control index of regional seawater intrusion risk assessment and the key factor to prevent seawater intrusion disaster.
Key words: seawater intrusion; AHP; EWM; risk evaluation; Laizhou City
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 Optimal Path Planning for Earthquake Evacuation Based on Location Assignment Model
Li Yutang, Zhao Jingzheng, Wang Minshui, Ye Yinghui, Wang Mingchang
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 2018-2028.   DOI: 10.13278/j.cnki.jjuese.20230235
Abstract1528)      PDF(pc) (7757KB)(50)       Save
 In colleges and universities with large population and density, scientific planning of earthquake evacuation paths in earthquake-prone areas is of great significance to the life and property safety of teachers and students. Based on the extraction of spatial distribution information and relevant survey  of Chaoyang Campus, Jilin University,    this study realizes the scientific planning of the evacuation paths of  daytime and nighttime simulated scenarios in the study area using  location allocation (LA) model  and  Dijkstra optimal path algorithm, combined with service domain analysis and  optimal path analysis. The results show that playgrounds, outdoor basketball courts, open meadows, and some large parking lots can be used as backup safety zones in the earthquake evacuation plan of universities. LA model and Dijkstra algorithm can meet the requirements of earthquake evacuation planning when evacuation directions do not conflict, and the capacity of the safety zone is large. In view of  the unbalanced space distribution of earthquake evacuation safety places in campus, some suggestions are put forward to improve the earthquake escape system in colleges and universities, such as balanced distribution of open space, increasing the facilities of earthquake evacuation, and strengthening the skills of earthquake evacuation.
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Prediction Method of the Distribution Position of Oil and Gas Transporting Form from Oil Source Fault to Sand Body: A Case Study of Sha-1 Lower Submember of Gangdong Fault in Qikou Area

Zhang Jinbao
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1352-1361.   DOI: 10.13278/j.cnki.jjuese.20230111
Abstract1528)      PDF(pc) (11060KB)(22)       Save

Gangdong fault is a critical reservoir-controlling fault in the north of Qikou sag. In order to study the oil and gas distribution of Sha-1 Lower Submember in the Gangdong fault of Qikou sag, there are two cases of oil and gas transporting forms recognized: The distribution position of the entire oil and gas transporting form from the Gangdong fault to the Sha-1 Lower Submember sand body was predicted based on the overlapping of the following three key factors, the transport site of the Gangdong fault in Sha-1 Lower Submember, the regional mudstone cap sealing site of Sha-1 Middle Submember, and the connected sandbody distribution site of Sha-1 Lower Submember. The distribution position of the partial oil and gas transporting form from the Gangdong fault to the Sha-1 Lower Submember sand body was predicted based on the overlapping of the following four key factors, the transport location of Gangdong fault within Sha-1 Lower Submember, the unsealed location of regional mudstone cap of Sha-1 Middle Submember, the distribution location of connected sandbodies of Sha-1 Lower Submember, and the overlying regional mudstone cover of Minghuazhen Formation. The results show that: The entire oil and gas transporting form is mainly distributed in the east and west, while partial oil and gas transporting form is mainly distributed in the middle and locally in the east. The distribution position of the entire and partial oil and gas transporting form controls the distribution of the entire oil and gas fault in Sha-1 Lower Submember of Gangdong fault.


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Research on Evolution Process and Impact Range Prediction of High Level Remote Collapse and Landslide-Debris Flow Disaster Chain:Taking the “4·5” Tiejiangwan Geological Disaster Chain in Hongya County,Sichuan Province as an Example
Liu Xin, Zhang Wen, Li Gen, Liu Bo
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1799-1811.   DOI: 10.13278/j.cnki.jjuese.20230258
Abstract1527)      PDF(pc) (44216KB)(72)       Save
 Since the 20th century, the frequency of geological disasters appearing in the form of disaster chains has significantly increased. Currently, there are few researches on the evolution process and impact scope of the disaster chain. In this paper, the evolution process of the disaster chain was illustrated taking the high-level remote landslide debris flow disaster chain in Tiejiangwan, Hongya County, Sichuan Province on April 5, 2021 as an example. The initiation source is high-level collapse, and a large number of falling rock blocks impact and load the rock and soil mass on the lower slope to form a landslide, and then the avalanche debris flow material of the landslide develops into a debris flow towards the Shuangxi River under the influence of rainfall. RAMMS software was used to numerically simulate and analyze the movement process of the debris flow, and its impact range was delineated under different rainfall frequency. The results show that the impact scope covers some scattered farmers in the upstream of Shuangxi Village under the frequency of rainfall in 20 a, the impact area covers the densely populated area of Shuangxi Village under the frequency of 50 a, and the impact area will continue to develop downstream and extend to the residential area of Laozhaohe under the frequency of 100 a. During the disaster chain, the maximum rainfall in the vicinity of Tiejiangwan close to the frequency of 10 a rainfall. It was found that the simulated results of the 10 year return period was consistent with the actual impact range, indicating that the simulation results were reliable.
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Effect of Freeze-Thaw Cycle on the Improvement of Dispersed Soil by Calcium Ion Agent
Yuan Xiaoqing, Wu Zeju, Wang Qing, Chen Huie, Lin Sen, Niu Cencen, Xu Xin
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1812-1825.   DOI: 10.13278/j.cnki.jjuese.20230295
Abstract1514)      PDF(pc) (10999KB)(15)       Save
 The dispersed soil has very poor water stability and is prone to damage such as pipe surges, caves, gullies and other damage. The seasonal frozen soil may enhance its dispersion during the freeze-thaw cycle in seasonal freezing area. In order to study the effect of different calcium agents on soil dispersion improvement and the influence of freeze-thaw cycle on the improvement effect, first,two kinds of calcium ionizers, calcium oxide and calcium chloride, were used to improve the dispersed soil in the western area of Jilin, and the optimum mixing dosage was determined to carry out the freeze-thaw cycle test. Then, the influence of freeze-thaw cycle on the improvement of soil dispersion was discussed by dispersive identification test, unconfined compressive strength test and microstructure test respectively. The test results showed that the improvement effect of calcium chloride on soil dispersion in western Jilin was better than that of calcium oxide, and the optimum mixing dosage of calcium oxide for improving dispersed soil was 1.6%, while the optimum mixing dosage of calcium chloride for improving dispersed soil only was 0.4%. The calcium chloride improved soil of 0.4% was used in freeze-thaw cycle test, it was still non-dispersive soil after different times of freeze-thaw cycle, and its unconfined compressive strength was a significant decline in the number of freeze-thaw cycles of 0-5 times. However, the decline tendency slowed down and the compressive strength was basically at 60 kPa after more than ten freeze-thaw cycles. By observing the scanning electron microscope images of the improved soil with 0.4% calcium chloride in different times of freeze-thaw cycles, it is assumed that the state of the cracks and pores of the improved soil tend to be stable after 10 times of freeze-thaw cycles. The above test results show that calcium chloride can be used as a good ameliorator to improve the soil dispersion in seasonal freezing zone.
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 Small Strain Dynamic Parameters of Dry Sand by Bender Element
Liu Hongshuai, Song Dongsong, Zhang Dongtao, Li Yanbing
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1826-1834.   DOI: 10.13278/j.cnki.jjuese.20230283
Abstract1512)      PDF(pc) (6309KB)(82)       Save
 The bender element is a commonly used method for testing small strain dynamic parameters of soil. However, when using bender element for testing, the waveform, frequency, peak value, and sample size can have a certain impact on the determination of the travel time of the wave in soil. At present, the influence of input wave on the travel time of output signal is mostly studid from the aspect of the frequency of input wave, but the the impact of the input wave peak and input waveform on the output signal is soldom studied. Therefore, in this paper the small strain dynamic parameters of dry Fujian standard sand were studied by bender element, and the effects of parameters such as input frequency, input wave peak, input waveform, relative density, and confining pressure on the constrained modulus, shear modulus, and Poisson’s ratio were analyzed. The results show that the input frequency has a significant effect on the travel time of S-wave(shear wave), and basically has no effect on P-wave(primary wave). The magnitude of the input wave peak has no effect on the travel time of S-wave or P-wave discrimination. The input waveform has a significant effect on the travel time of the S-wave or P-wave. The constrained modulus, shear modulus, and Poisson’s ratio of soil vary exponentially with the increase of confining pressure and pore ratio. Based on the small strain modulus prediction model proposed by Hardin, a three-dimensional model formula considering the coupling effect of confining pressure and pore ratio was fitted, which can provide certain reference for the estimation of constrained modulus, shear modulus, and Poisson’s ratio in practical engineering.
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Geochemical Characteristics and Organic Matter Enrichment of Black Shale in the Middle Ordovician Yanxi Formation in Central and Southern Hunan
Cai Linghui, , Yu Ye, , Guo Jianhua, Huang Yanran, , Guo Yuancao
Journal of Jilin University(Earth Science Edition)    2023, 53 (5): 1362-1379.   DOI: 10.13278/j.cnki.jjuese.20220171
Abstract1509)      PDF(pc) (16387KB)(48)       Save

In order to study the geochemical characteristics and enrichment patterns of the organic-rich black fine-grained rock series in the Middle Ordovician Yanxi Formation in the central and southern Hunan, samples from Ningyuan Mianhuaping (MHP), Shuangpai Hejiadong (HJD), Quanzhou Shazitang (SZT) and other sections are collected and analyzed for TOC, major elements,  trace elements and rare earth elements. The results show that the organic geochemical index of the Middle Ordovician Yanxi Formation in the central and southern Hunan is good, and the SiO2 content is high, which belongs to the high-quality source rock;The organic matter abundance of the black shale is relatively high, the average w(TOC)is 2.12%, which is generally higher than 2%, and the brittle mineral content is more than 50%, so it has good gas generating capacity. The large number of siliceous layers developed in the Yanxi Formation are mainly of sedimentary origin. The redox parameter U/Th,V/(V+Ni) and other indicators indicate that the overall water body is an oxygen-limited reductive environment, and the productivity of the Yanxi Formation was high; The terrigenous material input, redox environment, relative changes of sea level, and paleoproductivity affect the enrichment of organic matter together. The enrichment of organic matter in the shale of Yanxi Formation is mainly controlled by the anoxic environment, which belongs to the enrichment model of “deep-water retention basins”.




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 Influence of Thermal Deformation on Hydraulic Conductivity of Saturated Clayey Soil
Wang Fugang , Yang Guohua, Cheng Hui, Guan Xiaotong, Yuan Yilong
Journal of Jilin University(Earth Science Edition)    2023, 53 (6): 1835-1844.   DOI: 10.13278/j.cnki.jjuese.20230267
Abstract1501)      PDF(pc) (3186KB)(118)       Save
 In order to explore the mechanism of the effect of temperature changes on the permeability of clayey soil at 5-30 ℃, while considering the fluid properties induced by temperature changes and the influence of soil deformation on the hydraulic conductivity, and improve the application range and accuracy of the model, in this paper combination of laboratory experiments and theoretical models were used to study. Then, based on the experimental data of variable temperature seepage, a relationship equation between soil strain and medium void ratio was constructed. Finally, further modifications were made to the modified model of the Kozeny Carman model (REN model). The results show that in the common temperature range of 5-30 ℃ in groundwater, the deformation of soil caused by temperature changes has a significant impact on the hydraulic conductivity of clayey soil. The maximum calculation error of hydraulic conductivity can reach 40% under considering only the variation of fluid viscosity with temperature and ignoring the effect of clayey soil deformation. The modified model has better performance compared to existing hydraulic conductivity models. Through the analysis of the modified hydraulic conductivity model, it was found that the main controlling factor for the change in hydraulic conductivity is fluid viscosity when the temperature is in the range of 5-20 ℃, and has a small impact on the hydraulic conductivity with a degree of less than 10%. When the temperature is in the range of 20-30 ℃, the contribution rate of hydraulic conductivity induced by soil deoformation caused by temperature increase, and an maximum impact on the hydraulic conductivity exceeding 40%.
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Geochemical Characteristics and Genesis of Tuolahaihe Super-Large Graphite Deposit in Golmud, Qinghai Province
Lei En, Han Shijiong, Pang Xiaopeng, Hu Liancheng, Han Ziheng, Guo Rongqiang, Chen Yichen
Journal of Jilin University(Earth Science Edition)    2023, 53 (3): 853-865.   DOI: 10.13278/j.cnki.jjuese.20230095
Abstract1012)      PDF(pc) (11157KB)(127)       Save
 Tuolahaihe graphite deposit is the first super-large scale crystalline graphite deposit discovered in Qinghai Province, which is located in the southern margin of Qaidam basin and the middle part of East Kunlun. The ore bodies appear in bedded and near bedded within gneiss, calcareous gneiss, quartz schist and marble of the Lower Proterozoic Jinshuikou Group, which belong to a typical gneiss graphite deposit. In order to discuss ore genesis, detailed petrography, whole-rock geochemistry and isotope geochemistry studies have been carried out on the ore-bearing strata. The results show that ΣREE in graphite gneiss and graphite quartz schist containing graphite is 82.95×10-6-154.86×10-6,enriched in light rare earth elements, with obvious Eu negative anomaly and weak Ce negative anomaly, showing the protoliths formed in anoxic depositional environment of the shallow sea at the continental margin. The protoliths of ore-hosting metamorphic rocks are organic-rich sandy rocks, greywacke and calcium silicate rocks, and the material sources are mainly terrigenous debris and a small amount of them are shallow marine carbonate rocks. The δ13C isotopic composition of graphite gneiss and marble indicating that   the carbon in graphite comes from bioorganic carbon, while and carbon of marble is inorganic carbon. Tuolahaihe graphite deposit is a regional metamorphic graphite deposit that formed in Paleoproterozoic.
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 Large-Scale Epithermal Mineralization of Late Mesozoic and the Constraints of Deep Geological Processes on Mineralization in the Continental Margin of NE China
Sun Jinggui, Liu Yang, Xu Zhikai, Xu Zhitao, Chu Xiaolei, Gu Alei
Journal of Jilin University(Earth Science Edition)    2023, 53 (3): 651-692.   DOI: 10.13278/j.cnki.jjuese.20230034
Abstract993)      PDF(pc) (69646KB)(233)       Save
Epithermal deposits are important sources of nonferrous and precious metals as well as rare and critical metal resources such as indium. Due to their vectors toward deep porphyry mineralization, they have attracted the attentions of global geologists. The continental margin of Northeast China is one of the areas where epithermal ore deposits are widespread, characterized by epithermal Au and Ag-Pb-Zn-Cu polymetallic deposits being occur. According to the deposit geology, these epithermal-type deposits in Northeast China were divided into three types, low-sulfidation type (LS), intermediate-sulfidation type (IS) and high-sulfidation type (HS). The mineralization occurred in the Late Jurassic to Early Cretaceous volcanic basins and uplift areas spatially close to granite complex margins, comprising four separated mineralizationstages as a function of time, including (1) 151 to 141 Ma, (2) 140 to 131 Ma, (3) 123 to 120 Ma, and (4) 110 to 100 Ma. Stage 1 is restricted in the eastern portion of the Great Xing’an Range, characterized by regional epithermal HS copper polymetallic deposits. Stage 2 is developed in the western portion of the Great Xing’an Range, where large-scale epithermal LS-IS Ag-Pb-Zn mineralization. Stage 3 occurs in middle portion between the north of the Great Xing’an Range and the Lesser Xing’an Range and in Yanbian and western Liaoning, characterized by epithermal IS Cu and LS Te-Au mineralization. Stage 4 occurs in the Northern Great Xing’an Range-the Lesser Xing’an Range-Raohe-Dongning-Yanbian area. There is a younger mineralization time from the eastern portion of the Great Xing’an Range-the western portion of the Great Xing’an Range-the northern margin of the North China platform (Liaoxi+Yanbian)-the northern margin of the eastern portion of the Great Xing’an Range (Heihe) to the northern portion of the Great Xing’an Range-the Lesser Xing’an Range-Wanda Mountains-Taiping Mountains-Yanbian. There is a transition in mineralization type, from Cu polymetallic to Ag-Pb-Zn to Cu-Au + Te-Au to Au (± Sb) +large-scale Au and Cu. The tectonic environments for the various mineralization are related to the episodic subduction of ate Mesozoic Paleo-Pacific plate towards the eastern end of Eurasia, in which there is a transition from compressional to crustal extensional conditions. Except the mineralization in the Yanbian area occurring in the late stage of intermediate-basic volcanic eruption-hypabyssal emplacement, the remnant mineralization formed in the late stage of bimodal volcanic eruption-hypabyssal emplacement. Considering the genetic relation between epithermal metallic and porphyry Cu and Mo mineralization, the early-stage epithermal Ag-Pb-Zn-Cu mineralization and the coeval porphyry mineralization constitute the porphyry Mo-epithermal Ag-Pb-Zn system, whereas the epithermal LS Ag-IS Pb-Zn-HS Cu polymetallic and porphyry Cu-Mo mineralization constitute the porphyry Mo-Cu-epithermal Ag-Pb-Zn hydrothermal system. Similarly, the intermediate- and late-stage epithermal Au mineralization and Au-rich porphyry Cu mineralization constitute the Au-rich porphyry Cu-epithermal IS Cu-Au hydrothermalsystem and the Au-rich porphyry Cu-epithermal IS Cu-Au-epithermal HS Au (Cu) hydrothermal system. Nevertheless, more evidence is needed to clarify whether the epithermal LS Te-Au, Sb-Au, and Au deposits are individual ore system or not. Late Mesozoic epithermal ore systems are the results  the underplating of mantle-sourced basaltic magmas and their interactions with lower-crustal magmas during a roll-back of subducting slab and a thinning crust episode from Late Jurassic to Early Cretaceous.
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Metallogenic Regularity, Genetic Type and Potential Prospects of Cobalt Deposits in Northeast China
Zhang Yong, Ding Jianhua, Song Quanheng, Zhang Tong, Tai Yande, Sun Jinggui
Journal of Jilin University(Earth Science Edition)    2023, 53 (3): 693-712.   DOI: 10.13278/j.cnki.jjuese.20210351
Abstract985)      PDF(pc) (29927KB)(185)       Save
 Due to its unique physical and chemical properties, cobalt is widely used in modern advanced technology fields, so some countries have listed it as an important strategic critical resource. There are few independent cobalt deposits, and co-associated deposits are the main cobalt deposits. China is a country with relatively poor cobalt resources, with external dependence exceeding 90.0%. Many large and medium cobalt deposits have been discovered and explored in northeast China, including Cu-associated deposits and Cu-Ni-Fe co-associated deposits. Therefore, it is necessary to further summarize its metallogenic geological characteristics, analyze its resource potential, and provide a reference for future exploration. In this paper, cobalt deposits are classified into four main types, i.e., sedimentary-metamorphic type, magmatic type, marine volcano-sedimentary-metamorphic type, and skarn type. The sedimentary-metamorphic type and magmatic type cobalt deposits are widely distributed, mainly in the Paleoproterozoic Liaoning-Jilin rift zone. Combined with the geological characteristics of typical deposits, regional geochemical and geophysical characteristics, 28 prospect areas were further delineated, including 4 prospect areas of class A, 8 prospect areas of class B, and 16 prospect areas of class C. Finally, four class A prospect areas are recommended as the priority areas to focus on in the deployment of prospecting and exploration in the future.
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 Genesis and Its Tectonic Significance of Heishigou Basaltic Lava Dyke in Tianchi Volcanic Area, Changbai Mountain
Yan Donghan, Li Mengmeng, Xu Zhitao, Sun Liying, Ma Fei, Han Di
Journal of Jilin University(Earth Science Edition)    2023, 53 (3): 904-919.   DOI: 10.13278/j.cnki.jjuese.20210320
Abstract983)      PDF(pc) (21461KB)(139)       Save
In order to further understand the origin and tectonic setting of basaltic dyke related to Middle and Late Pleistocene volcanic activities in the Heishigou area of Tianchi volcano, based on remote sensing interpretation and field geological investigation, the  geochemistry, whole rock Sr-Nd isotope and geochronology analysis of the basaltic dykes were carried out. The results show that: 1) The major elements of the dykes have relatively high MgO, CaO, K2O and relatively low Na2O, belonging to the series of potassium, metaaluminous and subalkaline basalts. They are enriched in LILEs, such as Li, Cs, Be, Rb, Ba and Sr, and weakly enriched in HFSEs, such as Nb, Ta, Zr, Hf, U and Th, and the corresponding ratios of Zr/Hf, Nb/Ta and Th/U are 40.92-45.10, 15.77-16.34 and 3.49-3.76, respectively. 2) The values of (87Sr/86Sr)i and (143Nd/144Nd)i in the whole rocks range from 0.704 570 to 0.704 690 and 0.512 552 to 0.512 571, respectively, the εNd (t) values range from 0.87 to 1.45. The K-Ar isotopic ages of (0.35-0.34 Ma) obtained by previous research in dykes and tectonic-magmatic evolution together suggest that the basaltic magmatism occurred in the Chibanian stage of Late Pleistocene, and the diagenetic parent magma has the characteristics of enriched Ⅰ-type mantle source, with a small amount of lower crust components were added during the ascent of the magma, showing the characteristic of ocean island basalt (OIB). The formation of the basalt dykes and the contemporaneous volcanic activities occurred in a compressional tectonic environment at 0.35-0.34 Ma, which may be related to the rollback or subsidence of the Pacific plate after it was subducted into the northeastern Eurasia continent.
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Petrogenesis and Geological Significance of Late Carboniferous Monzogranite in Jiazishan Area, Inner Mongolia, China
Wang Zhenliang, Zhao Keqiang, Yang Jianzhou, Deng Youmao, Fu Yangang, Duan Zhuang, Lin Lujun, Zuo Guangming
Journal of Jilin University(Earth Science Edition)    2023, 53 (3): 984-1000.   DOI: 10.13278/j.cnki.jjuese.20210424
Abstract940)      PDF(pc) (14596KB)(75)       Save
The monzogranite in the Jiazishan of Inner Mongolia is located in the middle part of the Daxing’anling Mountains. To determine its intrusive age and tectonic environment, the geochronology and petrogeochemistry of the monzogranite have been systematically studied. The results show that the zircon U-Pb age of the monzogranite is (302.9±1.2) Ma, which is the product of Late Carboniferous magmatism. The monzogranite is characterized by high silica (w (SiO2)=74.73%-76.60%), rich alkali (w (Na2O+K2O)=6.20%-7.03%) and high aluminum saturation index (A/CNK=1.43-1.58), belonging to the high-K calc-alkaline series. Rb, K, Th and U are enriched, while Ba, Sr, Ti, Nb and P are obviously V-shaped depleted. The REE pattern shows a right-leaning enrichment type of LREE, with negative Eu anomaly (δEu=0.46- 0.67). The high differentiation index (ID) (88.89-91.55) and low solidification index (IS) (1.68-4.78) indicate that the monzogranite has undergone the evolution of high differentiation and is a type highly differentiation I-type granite with a tendency to evolve to A-type granite. The 176Hf/177Hf value is 0.282 850-0.282 951, the εHf (t) value is 9.2-12.5, and the two-stage mode age (TDM2) is 910-603 Ma, suggesting that the monzogranite may be the product of partial melting of juvenile crust in Neoproterozoic. The monzogranite in the Jiazishan area of Inner Mongolia was formed in the post-orogenic stage, and its formation may be related to the transformation of the tectonic setting from extrusion to post-collisional extension after the closure of the Paleo-Asian Ocean.
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Genesis and Diagenetic Geodynamic Background of Middle Jurassic Rhyolites in Derbur Area, Great Xing’an Range
Xu Zhitao, Li Mengmeng, Sun Jinggui, Sun Liying, Feng Jingqiao, Liang Xiaolong
Journal of Jilin University(Earth Science Edition)    2023, 53 (3): 866-886.   DOI: 10.13278/j.cnki.jjuese.20210316
Abstract935)      PDF(pc) (27056KB)(80)       Save
 The Middle Jurassic acidic volcanic-subvolcanic rocks are widely distributed in  Derbur area of the northern part of the western slope of the Great Xing’an Range. The rock assemblages are mainly composed of rhyolite, rhyolitic lithic tuff and quartz porphyry, and no systematic chronological and geochemical studies have been carried out on their diagenetic age, petrogenesis and diagenetic dynamic mechanism. In this paper, petrography, LA-ICP-MS zircon U-Pb dating, geochemistry and zircon Hf isotope studies were carried out on the rhyolites in  Biliya leal-zine polymetallic mining area. LA-ICP-MS single grain zircon U-Pb concordance age is (164.2±1.6) Ma (MSWD=7.7, n=14), belongs to Middle Jurassic. They have relatively high contents of major elements Si, K and Al, and belong to high-K, calc-alkaline and peraluminous rock series. Trace elements show that they are enriched in large ion lithophile elements, weakly enriched in high field strength elements, and obviously depleted in Ba, Sr, Ti and other elements.The ratios of Nb/Ta, Zr/Hf and Th/U are 13.05-22.36, 39.57-43.57 and 3.37-3.51, respectively. There are negative Eu anomalies in REE (the values of  δEu are 0.69-0.76), the ratios of LaN/YbN, La/Ce and La/Yb are  9.95-10.12, 0.48-0.50 and 14.13-15.05, respectively. In addition, they also have low 10 000Ga/Al (2.33-2.34) and (K2O+Na2O)/Cao (9.54-9.96) ratios. According to the calculation of Ti element in zircon, the saturation temperatures of zircon are between 683 and 756 ℃. These characteristics indicate that the Middle Jurassic rhyolite has the property of I-type rhyolite, and the diagenetic magma has the characteristics of volcanic arc or active continental margin magma. The 176Hf/177Hf ratios in zircons are 0.282 853-0.282 990, the corresponding εHf(t) values range from 6.22 to 10.83, and the two-stage Hf model ages range from 734.2 to 474.0 Ma, which are similar to the one-stage Hf model ages (592.6-410.1 Ma), indicating that their diagenetic magma is mainly derived from the partial melting of the juvenile lower crust. The magma was contaminated by crustal materials during the process of emplacement or diagenesis, and constituted the characteristics of “bimodal volcanic rocks” with the contemporaneous intermediate-basic volcanic rocks in this area. Combined with the temporal and spatial distribution of regional magmatic rocks and the evidence of geophysical data, it is further believed that the diagenetic geodynamic background of the Middle Jurassic acid lavas (rhyolite, rhyolitic lithic tuff and quartz porphyry) in this area is closely related to the passive continental margin which influenced by the subduction of the paleo-Pacific plate into Eurasia.
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Genesis and Tectonic Significance of Early Pleistocene Basaltic Lava in Longgang Volcanic Area: Evidence from Rb-Sr Isotopic Dating, Element Geochemistry and Pb Isotope
Xu Zhitao, Sun Liying, Li Zhongwei, Li Mengmeng, Liu Hongyan, Ma Fei
Journal of Jilin University(Earth Science Edition)    2023, 53 (3): 887-903.   DOI: 10.13278/j.cnki.jjuese.20210115
Abstract932)      PDF(pc) (20333KB)(111)       Save
 Longgang volcanic area is located in Huinan and Jingyu County, Eastern Jilin Province, and is an important part of the Quaternary continental volcanic rock area on the continental margin of Northeast China. In order to further explore the genesis and tectonic significance of basaltic lava in the study area, based on field geological investigation, Rb-Sr isotopic dating, element geochemistry and whole rock Pb isotopic analysis were carried out. The experimental results show that: 1) The Rb-Sr isochron age of whole rocks, plagioclase and amphibole from seven trachybasalt lava samples is (1.81 ± 0.34) Ma (MSWD=0.17, n=7). 2) The values of Na2O + K2O in trachybasaltic lavas range from 6.44% to 6.65%, with high A/CNK (1.24-1.27) and Mg# (39.09-39.81) values. Compared with the primitive mantle, the trachybasaltic lavas significantly enriched in Rb, Ba, Sr and other large ion lithophile elements (LILE), enriched in light rare earth elements (LREE), weakly enriched high field strength elements (HFSE) such as Nb, Ta, Zr, Hf, U and Th, depleted heavy rare earth elements (HREE), with weak Eu anomalies (δEu=0.95-1.07) and weakly enriched in Pb. 3) The (87Sr/86Sr) i values in the studied rocks range from 0.705 074 to 0.705 206, and the ratios of 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb in the whole rocks are 17.984-18.329, 15.490-15.523 and 38.315-38.400, respectively. Combined with the recent research results and the existing understanding of regional tectonic evolution, it shows that the diagenetic age of basaltic lava is the Calabrian stage of the Early Pleistocene. The diagenetic magma is mainly formed by mantle-derived magma, with a small amount of young lower crust components added, showing the attributes of oceanic island basalts (OIB) or intraplate metasomatic basalt. In addition, the formation of trachybasaltic lava and its associated volcanic activity occurred in an extensional tectonic environment at about 1.81 Ma, which may be related to the roll-back after the subduction of the Pacific plate under the northeastern Eurasia continent.
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Lithofacies Types and Genesis of Fine-Grained Sediments in Terrestrial Depression Lake Basin: Taking Upper Cretaceous Qingshankou Formation in Songliao Basin as an Example
Meng Qingtao, Hu Fei, Liu Zhaojun, Sun Pingchang, Liu Rong
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 20-37.   DOI: 10.13278/j.cnki.jjuese.20230314
Abstract929)      PDF(pc) (42719KB)(90)       Save
Shale oil is currently a hot and difficult topic in unconventional oil and gas research. The analysis of the types and genesis of fine-grained sedimentary lithofacies is an effective way to study the “source and reservoir” characteristics of shale oil and predict its “sweet spot”. The fine-grained sediments of the Qingshankou Formation in the Songliao basin are widely developed and are effective intervals for shale oil enrichment. Based on four parameters, including organic matter abundance, mineral composition, lithology, and sedimentary structures, six kinds of lithofacies of fine-grained sedimentary rocks of the Qingshankou Formation in the Songliao basin are divided in this paper, as clay shale with high content of organic matter and mud-grade lamination(A), felsic shale with medium-high content of organic matter and fine silt-grade lamination(B), felsic shale with medium-low content of organic matter and coarse silt-grade lamination(C), layered siltstone with low content of organic matter(D), layered ostracoid limestone with low content of organic matter (E) and layered dolomite with low content of organic matter (F). Then, the genesis of different lithofacies types were discussed from the perspectives of hydrodynamics and organic matter enrichment, and corresponding sedimentary models were established. In the static and salty water environment below the base of storm waves with high lake productivity, planktonic algae and clay flocs are uniformly suspended and settled, forming organic-rich clay lamination and lithofacies A is deposited. In a relatively static and brackish water environment below the normal wave base (with local turbulence near the wave base) with high lake productivity, the fine silt particles brought by delta runoff and flood flow continue to move towward the center of the lake basin, forming a felsic lamination through uniform suspension and sedimentation, and a clay lamination is formed during the period of intermittent suspension and sedimentation, and lithofacies B is deposited. Below the normal wave base, the flood which carries silt-grade particles are transported to the outer front of delta along the underwater distributary channel, and enter the front delta in the form of stable turbidity current. As the flow velocity gradually decreases, it forms a coarse to fine silt lamination, clay lamination is formed during the period of intermittent suspension and sedimentation, and lithofacies C is deposited. Below the normal wave base, the early sediments of the delta front, under the action of paroxysmal turbidity currents, collapse into deeper water, forming lithofacies D and E. Between the normal wave base and storm wave base, lithofacies F is formed in saline water environment under a relatively dry climate.

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 Petrogenesis and REE Occurrence State of Mesozoic Dachuan Alkaline Granite in Tonghua Area: Constraints from Geochemistry, Zircon U-Pb Dating and Hf Isotope
Zhang Tingting, Dong Guozhen, An Yuwei, Chu Xiaolei, Bai Chenglin, Sun Jinggui
Journal of Jilin University(Earth Science Edition)    2023, 53 (3): 946-963.   DOI: 10.13278/j.cnki.jjuese.20220290
Abstract923)      PDF(pc) (19037KB)(37)       Save
 The southern part of Jilin is located in the eastern section of the northern margin of the North China craton, which has experienced a long geological evolution in the Archean, Proterozoic, Paleozoic, Mesozoic and Cenozoic. The alkali-feldspar granite enriched in rare earth elements in the Late Mesozoic is widely developed in this area. In this paper, the Dachuan granite enriched in rare earth elements was selected to carry out petrography, zircon U-Pb dating and Hf isotope, petrogeochemistry analysis. The results show that the granite is mainly composed of fine-grained, medium-grained and coarse-grained biotite alkali-feldspar granite, followed by granite-pegmatite. The main elements have the characteristics of high silicon (w (SiO2) =72.56%-84.09%), low aluminum (w (Al2O3) =8.15%-14.76%), quasi aluminum-strong peraluminum (A/CNK= 0.98-1.60), belonging to the high potassium calc-alkaline series. The samples have a high rare earth mass fraction (w (ΣREE) =88.53×10-6-839.95×10-6), (La/Yb)N=2.30-41.24, enriched in light rare earth elements, depleted in heavy rare earth elements. The partition pattern of rare earth elements is right-leaning type, with obvious negative Eu anomaly and δEu value ranging from 0.05 to 0.60. The differentiation index (ID=86.72-97.69) is high, and the consolidation index (IS=0.16-1.13) is low, indicating that the magma evolution has experienced different degrees of separation and crystallization of plagioclase, biotite, apatite and other minerals. Combined with the petrographic characteristics, the Dachchuan alkali-feldspar granite is preliminarily considered as highly differentiated granite. The single zircon U-Pb isotopic age of coarse-grained biotite alkali feldspar granite is (120.8±1.6) Ma. The εHf(t) values of zircons are all negative (-10.7--5.2), and the corresponding Hf isotope second-order model ages of the zircons are 2 587-2 090 Ma. Based on isotope and petrogeochemical data, the initial magma originated from partial melting of the Neoarchean and Paleoproterozoic continental crust, and the rock mass was the product of magma emplacement after magma crystallization differentiation in the homologous magma chamber. Mineral identification and whole rock trace elements show that with the evolution of magma, the quartz content gradually increased, the biotite content gradually decreased, and the total rare earth contents also gradually decreased. The rare earth elements are mainly enriched in coarse-grained biotite alkali feldspar granite phase.
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Petrogenesis and Geodynamic Setting of Mesozoic Intermediate-Acid Complex in Dashihu-Dataizi Copper Mineralization Area, Ji’an, Southern Jilin Province
Chang Xiang, Sun Jinggui, Chen Xu, Liu Yanpeng, Bai Chenglin, Xu Zhikai
Journal of Jilin University(Earth Science Edition)    2023, 53 (3): 920-945.   DOI: 10.13278/j.cnki.jjuese.20230064
Abstract922)      PDF(pc) (65532KB)(43)       Save
 Hydrothermal copper mineralization in the Dashihu-Dataizi area of Ji’an area, southern Jilin Province is closely related to the intermediate-acid complexes such as monzonite diorite, diorite porphyrite, monzonite porphyry and syenite granite. In order to determine the lower limit of metallogenic ages and geodynamic background, the lithography, zircon U-Pb isotopic geochronology, geochemistry and zircon Lu-Hf isotope of the medium-acid complex have been studied on the basis of field investigation. The results reveal that monzonite diorite, diorite porphyrite, monzonite porphyry and syenite granite are all products of the Early Cretaceous magmatism, and the zircon U-Pb crystallization ages are (122.7±1.8)(122.0±1.9)(120.1±1.5) and (121.4±1.9) Ma, respectively. The magma emplacement of the mineralized system occurred in the Early Cretaceous (122.7-120.1 Ma), indicating that the mineralization age of the Dashihu-Dataizi copper mineralization area was later than or approximately equal to 120.1 Ma. The geochemical data reveal that they are all enriched in light rare earth elements (LREEs) and large ion lithophile elements (LILEs), relatively depleted in high field strength elements (HFSEs) such as Nb, Ta and Ti, and the Eu anomaly is not obvious. All of them present high potassium calc-alkaline quasi-aluminous rocks, which are the products of different evolutionary sequences of homologous magmas. The results of zircon Lu-Hf isotope analysis shows that εHf(t) values of monzonite diorite range from -7.5 to -5.2 and TDM2 range from 1 647 to 1 500 Ma, and εHf(t) values of syenite granite range from -13.1 to -4.2 and TDM2 range from 2 004 to 1 445 Ma, fLu/Hf ranges from -0.99 to -0.95, indicating that the magma originated from the partial melting of ancient crustal materials in the Mesoproterozoic, during which there was the addition of mantle end-member materials, and the ancient materials were mixed during the ascent and emplacement of the syenogranite magma. Combined with relevant research results, it is concluded that the Early Cretaceous granitic magmatism in the study area was formed in the extensional environment formed by the subduction and roll-back of the Paleo-Pacific plate to Eurasia.
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Origin and Evolution of Ore-Forming Fluids of the Sandaocha Gold Deposit in the Jiapigou Glod Ore Concentration Area, Jilin Province: Constraints from Fluid Inclusions and H-O Isotopes
Zhang Xiaotian, Sun Jinggui, Han Jilong, Wang Shu, Yu Ridong, Liu Yang, Feng Yangyang
Journal of Jilin University(Earth Science Edition)    2023, 53 (3): 748-766.   DOI: 10.13278/j.cnki.jjuese.20210324
Abstract915)      PDF(pc) (30080KB)(63)       Save
The Jiapigou gold ore concentration area, located in the collage section between the northeastern margin of the North China craton and the Xing’an-Mongolian orogenic belt, is one of the most important gold-producing areas in China. However, the origin of the ore-forming fluids and genetic types of the gold deposits in the Jiapigou gold ore concentration area  are still widely disputed. Moreover, there is still a chronic lack of systematic research on evolution of the ore-forming fluids and ore-forming mechanism. To address the problems above, this paper selects the most representative Sandaocha gold deposit in the Jiapigou gold ore concentration area  as an example to carry out a detailed analysis of fluid inclusions, laser Raman spectroscopy and H-O isotopes. Four stages of mineralization have been identified in the Sandaocha gold  deposit: (Ⅰ) milky quartz, (Ⅱ) quartz-pyrite, (Ⅲ) quartz-polymetallic sulfide, and (Ⅳ) quartz-carbonate. The stages Ⅱ and Ⅲ represent the main gold mineralization. Three types of primary fluid inclusions (FIs) are identified in quartz formed at different stages: NaCl-H2O-CO2 (C-type), NaCl-H2O (W-type) and pure CO2 (PC-type). The early-stage quartz contains C- and W-type FIs, which have homogenization temperatures of 283-411 ℃ and salinities of 4.26%-17.48% NaCl equiv. The main-stage quartz contains all three types of FIs, with homogenization temperatures of 210-288 ℃ and salinities of 2.07%-15.76% NaCl equiv. The late-stage quartz contains only W-type FIs with homogenization temperatures of 131-210 ℃ and salinities of 2.57%-14.04% NaCl equiv. The H-O isotope results indicate that the initial ore-forming fluid is the mixture of magmatic water and a small amount of meteoric water, and the meteoric water was continuously added to the ore-forming fluids during mineralization. The ore-forming fluid system evolved from a moderate-temperature and moderate- to low-salinity NaCl-H2O-CO2 system in the early stage to a NaCl-H2O system with a low temperature and salinity in the late stage. Water-rock interactions generally occurred between ore-forming fluids and metamorphic wall-rocks during fluids migration. The sudden decompression and the addition of meteoric water led to fluid immiscibility and the exsolution of CO2, H2S, and other volatiles. This process destroyed the stability of Au-S complexes and facilitated the precipitation of gold and other ore-forming elements. Comprehensive studies of geology, fluid inclusions and H-O isotopes confirm that the Sandaocha gold deposit is a mesothermal hydrothermal vein gold deposit.
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 Geochronology of Lengshuigou Cu-Mo-Au Deposit in the Shanyang-Zhashui Area of South Qinling and Its Geological Significance
Chen Lei, Yan Zhen, Liu Kai, Dai Junzhi, Guo Xianqing, Nie Xiao, Pang Xuyong
Journal of Jilin University(Earth Science Edition)    2023, 53 (3): 713-727.   DOI: 10.13278/j.cnki.jjuese.20210430
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 Lengshuigou Cu-Mo-Au deposit is located in the Shanyang-Zhashui ore concentration area, and is one of the representative deposits of the Late Mesozoic porphyry-skarn Cu(Mo) deposits in the South Qinling orogenic belt. In addition to the porphyry-skarn Cu-Mo mineralization, structural-altered rock-type Au mineralization in the Lengshuigou deposit is also developed, but there are always doubts about whether there is a genetic connection between Cu-Mo mineralization and Au mineralization. Therefore, Re-Os dating of molybdenite from the porphyry-skarn Cu-Mo mineralization and 40Ar-39Ar dating of altered potassium feldspar and sericite from structural-altered rock-type Au mineralization were carried out, respectively, in order to be able to pass mineralization ages to determine their genetic relationship between the two mineralization types. The results show that the Re-Os isochron age of molybdenite is (147.4±8.4) Ma, the 40Ar-39Ar ages of the altered potassium feldspar and sericite are 144 Ma, and these ages are consistent within the error range. It indicates that the porphyry-skarn Cu-Mo mineralization and structural-altered rock-type Au mineralization were formed in the Late Jurassic-Early Cretaceous, and they are the products of the same mineralization and magmatic events in the South Qinling orogenic belt. Combined with the regional tectonic evolution, the results show that the Lengshuigou Cu-Mo-Au deposit was formed in the background of the tectonic regime transition of the Qinling orogenic belt during the Late Mesozoic. In addition, the metallogenic epoch of Lengshuigou Au mineralization also shows that the Late Jurassic-Early Cretaceous Au mineralization existed in the South Qinling orogenic belt, which has important indicative significance for regional gold exploration.
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 Zircon U-Pb Geochronology, Geochemical Characteristics and Geodynamic Significance of the Early Jurassic Syenogranite in Kaoshan Area of Central Jilin Province
Ye Xiqing, Sun Liying, Xu Zhitao, Yan Donghan, Feng Jingqiao , Cao Rongji
Journal of Jilin University(Earth Science Edition)    2023, 53 (3): 964-983.   DOI: 10.13278/j.cnki.jjuese.20210147
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 The Early Jurassic medium-grained syenogranite in Kaoshan area of central Jilin Province is exposed in the southern part of Zhangguangcai range, and emplaced in contact with the Middle Triassic granitoids and Devonian-Carboniferous intrusive rocks. Its main rock-forming minerals are composed of K-feldspar, quartz, plagioclase and biotite. In order to explore the diagenetic age, geochemical characteristics and geodynamic background of the granites in Kaoshan area, we carried out petrographic, chronological, geochemical and Hf isotope studies on the Early Jurassic non-orogenic A-type medium-grained syenogranite exposed in the study area. Zircon U-Pb geochronology and geochemical studies show that: The concordant age of the medium-grained syenogranite in the study area is (193.2±0.9) Ma, and the diagenetic time should be attributed to the Early Jurassic. It has a high SiO2 (75.49%-75.82%) and total alkali (8.28%-9.17%) mass fraction, together with high A/CNK (1.08-1.13), LREE (20.89×10-6-46.38×10-6) and FeO/MgO (3.29-5.83) values. It is also enriched in large ionic lithophile elements (LILE, such as Rb, K and Pb) and high-field strength elements (HFSE, such as Th, U, Hf, Nb and Zr). It has low MgO (0.06%-0.14%), TiO2 (0.05%-0.12%), P2O5 (0.02%-0.04%), Sr (24.20×10-6-62.59×10-6), HREE (5.14×10-6-11.80×10-6) mass fraction and medium δEu (0.41-0.56) value, which is similar to the lithogeochemical characteristics of non-orogenic A-type granite.  Hf isotopic analysis results of zircons show that the εHf (t) values range from 9.7 to 15.7, and the two-stage Hf-isotope model ages (TDM2) range from 612 to 225 Ma. Combined with the regional research data, we think the diagenetic parent magma of the medium-grained syenogranite in the Kaoshan area was probably derived from the juvenile lower crust in an extensional environment. The tectonic environment of asthenosphere mantle upwelling and back-arc extension caused by the subduction of the early paleo-Pacific plate, may be an important geodynamic factor for the Early Jurassic non-orogenic A-type granitic magmatism in the study area.
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The Relationship Between Isotopic Compositions of Metals, Non-Metal, and Rare Gases in Seafloor Hydrothermal Sulfides and Its Geological Significances
Zeng Zhigang
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 1-19.   DOI: 10.13278/j.cnki.jjuese.20230310
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The isotopic composition of seafloor hydrothermal sulfides can not only trace their sources but also record the fluids and their precipitation processes. This article analyzes the isotopic compositions of metals (lead, rhenium, osmium, iron, copper, zinc), non-metal (sulfur), and rare gases in fluid inclusions of global seafloor hydrothermal sulfides, and explores the relationship between the isotopic compositions of metals, non-metal, and rare gases in sulfides. The results indicate that there is a negative correlation between sulfur isotopic composition and osmium, iron isotopic compositions, as well as between iron, lead, and helium isotopic compositions in seafloor hydrothermal sulfides. There is a positive correlation between osmium isotopic composition and iron isotopic composition, and between xenon isotopic composition and lead, osmium isotopic compositions. During the stage of magma degassing and material injecting fluid, sulfides are formed with the characteristics of low δ34SVCDT values (about 0‰) and high 3He/4He (>8 Ra), 40Ar/36Ar (>300), and 129Xe/132Xe (>0.99) ratios. In the stage of fluid-rock interaction, as lead-containing minerals in the rock continue to dissolve, i.e., the degree of fluid-rock interaction increases, the lead content of pyrite, chalcopyrite, and sphalerite precipitated in the fluid increases, accompanied by a slight decrease in the 206Pb/204Pb ratios. In the fluid-seawater mixing stage, with the increase of seawater influence degree, the Os content (about 0×10-9) in sulfides can sharply decreased, and the δ57Fe value (<-1.6‰), the 187Os/188Os ratio (>1)  significantly increases; With the enhancement of fluid-seawater mixing degree, the δ34SVCDT values of pyrite in sulfides will increase with a slight decrease in the 3He/4He, 40Ar/36Ar, and 129Xe/132Xe ratios in its fluid inclusions, while their 3He/4He ratios will decrease with a decrease in its 130Xe/132Xe ratios. The above indicates that by comprehensively analyzing the isotopic composition and content of metals, non-metal, and rare gases, and discussing their relationships, the effects of magma degassing, fluid-rock interaction, and fluid-seawater mixing on seafloor hydrothermal circulation can be revealed, and the degree of fluid-rock interaction and fluid-seawater mixing during sulfide precipitation can be understood.

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 Metallogenic Fluid Properties and Mineralization Mechanism of Jinya Gold Deposit in Northwest Guangxi
Li Xinhang, Bai Ling’an, Hu Qiaofan, Xie Lanfang, Pang Baocheng, Yue Zhiheng
Journal of Jilin University(Earth Science Edition)    2023, 53 (3): 840-852.   DOI: 10.13278/j.cnki.jjuese.20210327
Abstract907)      PDF(pc) (17455KB)(52)       Save
Jinya gold deposit is one of the typical Carlin-type gold deposits in the “Golden Triangle” area of Yunnan, Guizhou and Guangxi provinces. The ore bodies are obviously controlled by fault structures and are mainly layered, pod-shaped, and lenticular in argillaceous siltstone and silty mudstone of the Middle Triassic Baifeng Formation. In order to explore the metallogenic fluid properties and mineralization mechanism, the petrographic study, micro temperature measurement and Laser Raman spectroscopy analysis on the fluid inclusions in the study area were carried out. The metallogenic hydrothermal process of this deposit can be divided into three metallogenic stages: Quartz-pyrite stage (Ⅰ), pyrite-arsenopyrite stage (Ⅱ) and quartz-carbonate stage (Ⅲ), and stage Ⅱ is the main metallogenic stage. The petrographic study of fluid inclusions shows that the fluid inclusions in the metallogenic period are mainly two-phase vapor inclusions, and the liquid phase is mainly water; The gas composition is mainly CO2, N2, SO2 and CH4, and the average homogenization temperature from Ⅰ stage to Ⅲ stage is 189, 157, and 137 ℃, respectively; The average w(NaCleq) is 6.01%, 4.18%, and 2.01% in sequence. The initial ore-forming fluid is characterized by H2O-NaCl system fluid with medium-low temperature, low salinity, low density and contains volatile components such as CO2, N2 and SO2. In the early stage of mineralization, the hot brine in the basin with medium-high temperature and reducibility had a strong water-rock reaction with the surrounding strata, activating and migrating Au and S; In the main metallogenic period, the ore-forming fluid continuously flows upward driven by abnormally high pressure and faulting activities, and reacts with Fe and other elements in dolomite to form pyrite and arsenopyrite. At the same time, it mixes with atmospheric precipitation, the temperature and salinity drop rapidly, and Au and other ore-forming elements are unloaded in large quantities. In the late stage of mineralization, the ore-forming elements in the fluid were consumed, the atmospheric precipitation continued to mix in, the temperature and salinity dropped significantly, and the mineralization ended. The mineralization mechanism is fluid mixing and water-rock reaction.
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 Au Mineralization Process in the Jiapigou Mining District of Northeast China: Evidences from U-Pb Dating and Trace Element of Zircon of the Binghugou Gold Deposit
Han Jilong, Sun Jinggui, Zhang Yong, Zhang Xiaotian, Liu Yang, Wang Shu, Chu Xiaolei
Journal of Jilin University(Earth Science Edition)    2023, 53 (3): 728-747.   DOI: 10.13278/j.cnki.jjuese.20210414
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 The Jiapigou mining district (JMD) is famous in the world for its numerous quartz vein- and altered rock-type gold deposits. The gold deposits in the JMD belong to mesothermal gold deposits and are characterized by fluids with moderate temperature and low salinity, Middle Jurassic mineralization, and genesis related to synchronic magmatism. In order to depict the process of synchronic magmatism-hydrothermalism, and tace the process of Au mineralization in this region, we present the deposit geology, petrology, and mineralogy, geochronology, and geochemistry of zircon from the Binghugou gold deposit in the JMD. The results show that: 1) Gold mainly occurs in cements of the shattered breccia; 2) Based on the morphology, internal structure, trace element composition, and U-Pb age, the zircons in the cements of the hydrothermal breccia and breccia-type ore can be divided into the captured (Group Ⅰ: 195-185 Ma), inherited (Group Ⅱ: 175-172 Ma) and hydrothermal zircons (Group Ⅲ: 176-173 Ma), and the U-Pb age of the hydrothermal zircons (Group Ⅲ) at 176-173 Ma indicating that Au mineralization occurred in the Middle Jurassic; 3) The zircons in the Groups Ⅱ-Ⅲ have low w(Y) values and high Y/Ho ratios, indicating that the late stage granitic melts coexist with the P- and Ti-rich hydrothermal fluids, and have systematic trends between w(Hf)-Th/U and w(Hf)-Yb/Gd, indicating that magma experienced gradual cooling and differentiation, and finally formed hydrothermal fluid; 4) The Ce/Ce* and Eu/Eu* ratios of the Group Ⅱ zircons are obviously higher than those of the Group Ⅲ zircons, indicating that the magma has high oxygen fugacity, and the hydrothermal fluid has low oxygen fugacity, while the values of the incompatible elements (P, Y, LREE, Nb, Th, and Pb*) gradual increase with the increase of the values of w(Hf) of the zircons (from the Group Ⅱ to Ⅲ), indicated that incompatible elements gradually entered the hydrothermal fluid phase and enriched during magmatic differentiation and magmatic-hydrothermal transition. Combined the geological observations, the magma is characterized by high temperature, high oxygen fugacity and volatile-rich components, which hindered the crystallization of sulfides in the early stage of its evolution, and promoted the enrichment of Au, S, Fe and incompatible elements in the late stage of its evolution/ hydrothermal fluid, resulting in the formation of the initial ore-bearing fluids. In the process of upward migration, abundant gold and sulfides precipitated from the ore-bearing fluids due to its unstable state caused by the intense fluid-rock interaction and decrease of pressure, temperature and oxygen fugacity, resulting in the formation of gold deposit. Combined with the regional metallogenic setting, ore geology, element geochemistry, ore-bearing fluid, and chronology of magmatism and mineralization, the above geological process is likely to have resulted in the giant gold mineralization observed in the JMD.
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Zircon U-Pb Geochronology, Geochemistry and Tectonic Environment of the Volcanic-Subvolcanic Rocks at Yidong Linchang Gold Polymetallic Deposit, Lesser Xing’an Range (Northeast China)
Zhao Zhonghai, Liang Shanshan, Sun Jinggui, Wang Xing, Li Chenglu, Zhou Jiazheng, Jing Zhaoyi
Journal of Jilin University(Earth Science Edition)    2023, 53 (3): 785-808.   DOI: 10.13278/j.cnki.jjuese.20210317
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 Yidong Linchang gold polymetallic deposit is a recently discovered gold deposit in Lesser Xing’an range. The volcanic-subvolcanic rocks are widely distributed in the mining area, among which the diorite porphyrite and dacite are closely related to the mineralization. In this contribution, we reported petrogeochemistry,zircon U-Pb ages and Sr, Nd and Hf isotope compositions of the diorite porphyrite and dacite at Yidong Linchang gold polymetallic deposit. Geochemical studies show that the volcanic-subvolcanic rocks closely related to mineralization are peraluminous calc-alkaline volcanic rocks. All these rocks have arc magma characteristics related to subduction and are enriched in LREEs and weak negative Eu anomaly, enriched in large-ion lithophile elements (Rb, Ba) and incompatible elements (Th, U), and relatively depleted of high field-strength elements (Nb, P and Ti). Zircon U-Pb ages of diorite porphyrite and dacite are (99.60±0.62) Ma and (98.50±0.50) Ma, respectively, both formed in the Early Cretaceous. Sr-Nd-Hf isotope analysis showed that the samples have high (87Sr/86Sr)i ratios (0.707 20-0.707 70), low εNd(t) values (-3.47--2.42) and εHf(t) values (-2.22-4.11), revealing that the source area is mainly mantle with the strong contamination of crustal materials. Research results reveal that the diorite porphyrite and dacite in Yidong Linchang gold polymetallic deposit were formed in the continental arc environment of the active continental margin. The magmas were likely derived from deep-formed magmas by the partial melting of the overlying mantle wedge by the fluids released by the dehydration of the subducting Pacific Oceanic plate, and are strongly contaminated by the crust during the evolution process. On the basis of the above research and combined with the regional geological background, it is inferred that the volcanic-subvolcanic rocks of the Early Cretaceous were formed in the tectonic background of lithospheric extension as a consequence of the rollback of the subducted Paleo-Pacific Oceanic plate.
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 Geochronology and Ore-Forming Fluid Characteristics of Baituyingzi Molybdenum Deposit, Inner Mongolia
Zhao Keqiang, Sun Jinggui, Cheng Lin, Ma Shengming, Wang Zhenliang, Gu Alei
Journal of Jilin University(Earth Science Edition)    2023, 53 (3): 822-839.   DOI: 10.13278/j.cnki.jjuese.20210363
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Baituyingzi molybdenum deposit is located in the south of the Xilamulun molybdenum metallogenic belt, which is a new exploration discovered medium porphyry type molybdenum deposit in recent years. This paper reports the geological characteristics, Re-Os age of molybdenite, fluid inclusions and H-O-S-Pb isotope data of  Baituyingzi molybdenum deposit to determine its metallogenic age and fluid characteristics. Molybdenum mineralization mainly exists in veinlet-disseminated, breccia-type and vein-type forms in Indosinian granite porphyry. The Re-Os isochron age of (245.4 ± 4.1) Ma for the molybdenite indicates that molybdenum mineralization occurred in the Middle Triassic. Four types of inclusions were identified: gas-liquid two-phase inclusions (W), CO2-bearing three-phase inclusions (C),  daughter crystals-bearing three-phase inclusions (S) and pure gas-phase inclusions. The Ore-forming fluid in the early stage of mineralization belongs to the CO2-H2O-NaCl system with medium-high temperature and medium-low salinity, while the main mineralization stage is characterized by medium temperature, high-salt and low-salinity coeval, and the gas-phase composition is gradually transformed into H2O-based. The fluid undergoes immiscibility during the ore-forming process, accompanied by the separation and precipitation of a large number of metal minerals. With the continuous reduction of temperature and pressure, and the addition of atmospheric water, the fluid evolved into H2O-NaCl system with medium-low temperature and low salinity and low CO2 in the late stage of mineralization. Combined with the H-O-S-Pb isotopic data, it is believed that the ore-forming materials are mainly derived from the mantle, the crust-derived materials are added in the late stage of mineralization, and the source of the crust-mantle mixture as a whole. The ore-forming fluid is derived from magmatic hydrothermal solution in the early stage, atmospheric water is added in the late stage. Therefore, we suggest that  Baituyingzi porphyry-type molybdenum deposit was formed in the post-orogenic extension environment in the Early-Middle Triassic. The source of the ore-forming materials in porphyry molybdenum deposits is mainly crust-mantle mixed or crust, while the source of ore-forming materials of copper is mantle. The oxygen fugacity and pH value of the fluid are two of the main factors for the precipitation of molybdenite.
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Micro Pore Throat Structure and Fractal Characteristics of Tight Sandstone Reservoir#br#
Liu Shuo, Wang Fei, Yu Rui, Gao Jianxing, Shi Hao, Zhu Yushuang
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 96-107.   DOI: 10.13278/j.cnki.jjuese.20220166
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The quantitative evaluation of pore throat microstructure has always been a hot and difficult point in the study of tight sandstone reservoirs. Taking fractal dimension as a breakthrough point, 12 core samples of Chang 6 Member of Yanchang Formation of Upper Triassic were collected from different wells in Zichang area of Ordos basin. The pore throat structure and fractal characteristics of tight sandstone samples were studied by means of scanning electron microscope, casting thin section, high pressure mercury injection and other experimental methods and fractal theory. The results show that the pore types of tight sandstone reservoirs in the study area are mainly composed of residual intergranular pores, dissolution pores and intercrystal pores. There is a obvious negative correlation between total fractal dimension and porosity and permeability, which indicates that the complexity and heterogeneity of pore throat structure of tight sandstone reservoirs in the study area have a certain impact on the physical properties. The correlation between the fractal dimension of mesopores and pore throat structure parameters is better, which indicates that the heterogeneity and surface roughness of mesopores mainly affect the reservoir space and seepage properties. There is a positive correlation between the quality of tight sandstone reservoir and the fractal dimension. The more favorable the reservoir is for oil and gas enrichment, the smaller the corresponding fractal dimension is.
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Sedimentary Characteristics and Evolution Model of Middle and Lower Ordovician in Tahe Area, Tarim Basin#br#
Guo Chuntao, Shi Jiangtao, Liu Liang, Jing Xueting, Liu Yangjin
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 68-82.   DOI: 10.13278/j.cnki.jjuese.20220206
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The environment plays a fundamental role in the development of karst reservoirs and affects the scale and strength of karst bodies. Strengthening the study of sedimentary environments can be beneficial to the exploration and prediction of high-quality karst reservoirs. In order to deeply understand the sedimentary characteristics of the Middle and Lower Ordovician in Tahe area, the sedimentary environment is finely identified and divided by using core, logging, seismic and regional macro-sedimentary data on the basis of field survey. At the same time, the petrological and petrographic indicators, such as rock color, type and combination, structure, paleontology, geochemical characteristics, and so on, are also used to identify sedimentary environments. The results show that the rock types in the study area are mainly granular limestone, micritic limestone, biological limestone and transitional rocks. There are five types of sedimentary environments developed in total. The Penglaiba Formation is dominated by restricted and semi-restricted platform, and the Yingshan Formation is dominated by semi-restricted platform and open platform, while the Yijianfang Formation is dominated by open platform, platform margin and submerged platform. A total of 11 seismic facies are developed, which have an obvious corresponding relationship with various sedimentary facies. In general, the study area is dominated by platform facies, with obvious differences in space-time evolution. Vertically, the sea waterbody gradually deepens from the Penglaiba Formation to the Yijianfang Formation, and the sedimentary environment gradually changes from restricted to open platform. Laterally, the main body of the study area is dominated by open platform and platform margin, and gradually transits to slope and basin facies from east and south to the outside of the study area. Based on previous data, the evolution model of the study area is established. This model shows that the sedimentary environment has evolved gradually from restricted platform of the Lower Ordovician Penglaiba Formation →semi-restricted platform → open platform of the Middle and Lower Ordovician Yingshan Formation → platform margin of the Middle Ordovician Yijianfang Formation → submerged platform of the late Yijianfang Formation and the Tumuxiuke Formation.
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Detailed Characterization of Neogene Relative Sea Level Change in Pearl River Mouth Basin and Its Control over Delta Sedimentary Evolution:Taking Hanjiang Formation and Zhujiang Formation of Oilfield A in Enping Sag as an Example

Wang Hua, Dai Jianwen, Chai Yukun, Heng Liqun, Song Gang, Sun Shuang, Li Rui
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 359-370.   DOI: 10.13278/j.cnki.jjuese.20220279
Abstract871)      PDF(pc) (20018KB)(13)       Save
Oilfield A in Enping sag was located in the ancient Pearl River delta front in the Neogene period. The sand bodies were generally thin, which made it difficult to predict the reservoir. The alternating of fluvial and oceanic processes also complicated the sedimentary microfacies transformation. These factors affect the increase of reserves and production in the future. Concerning the above problems, based on fine layer correlation and logging interpretation results, the average sandstone volume fraction in sand sets is used to characterize the relative sea level changes according to the characteristics of flat terrain and fewer changes in stratum thickness of ancient delta. Research shows that the average sandstone volume fraction of Zhujiang Formation and Hanjiang Formation in the study area can better represent the relative sea level changes and accurately describe the fifth order relative sea level change. By analyzing the sedimentary microfacies of sand sets, it revealed a good correspondence between relative sea level changes and the sedimentary microfacies evolution of deltas. The feasibility of characterizing relative sea level changes based on the average sandstone volume fraction of sand layers was verified, which can be used to predict the evolution of deltas and the superposition relationship of sand bodies.
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Source and Sink System and Exploration Practice in Early Wenchang Period  on  East Side of Huilu Low Uplift
Lei Yongchang, Qiu Xinwei, Wu Qiongling, Zhu Hongtao, Xiao Zhangbo, Li Min
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 413-428.   DOI: 10.13278/j.cnki.jjuese.20220340
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The east side of Huilu low uplift is Lufeng south hydrocarbon rich depression. In order to clarify the source and sedimentary reservoir distribution law on the east side of the low uplift, the research comprehensively uses the drilling and 3D seismic data to restore the ancient source area, describe the source to sink system elements, predict the plane distribution of sand rich sedimentary bodies, and discuss the control factors of sand body differential enrichment. The results show that Huilu low uplift develops a complete source and sink system controlled by paleogeomorphology. The lower Wenchang Formation of Paleogene in the study area can be further divided into eight uplift group units: A-H. On the basis of paleogeomorphology restoration, the eight uplift group units can be divided into 17 source and sink systems composed of independent watersheds and corresponding sedimentary areas. Among them, six independent source and sink systems composed of Watershed 1-6 are developed on the east side of Huilu low uplift, and Watershed  2, 4, and 6 have a large denudation range and denudation strength, and a large number of water systems, which are relatively concentrated. They are the main dominant source supply areas. The large denudation area, granite and volcanic rocks in Watershed 2 (eastern gentle slope of Lufeng 13 east sag) provide the material basis for the development of a large braided river delta and high quality reservoirs. The advantageous convergence of multiple water systems provides good development conditions for high-quality underwater distributary channel sandstone reservoirs.

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Micropore Structure Evaluation of Chang 7 Tight Sandstone in Zhijing-Ansai Area, Ordos Basin#br#
Yu Guangzhan, Wang Jian, Wu Nan, Xu Qinghai, Liu Xianfeng, Fu Qingmeng
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 83-95.   DOI: 10.13278/j.cnki.jjuese.20220270
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The study of micropore structure in reservoirs is of great significance for oil and gas exploration and development. This article uses experimental methods such as nitrogen adsorption, blue-dye thin section observation, scanning electron microscopy (SEM) observation, X-ray diffraction (XRD), and nuclear magnetic resonance to study the micropore structure of the tight sandstone in the Yanchang Formation 7 Member of the Zhijing-Ansai area. The pore structure parameters and distribution are calculated, and the types of micropores are analyzed. The mineral composition, particle size, and sorting parameters that affect the development of micropores are discussed. The results show that the lithology of the Chang 7 Member is mainly feldspar sandstone. The micropore structure of tight sandstone is complex, mainly existing in the form of clay intergranular dissolution pores, feldspar dissolution pores, etc. The Chang 7 Member mainly develops small pore throats, with an average pore volume of 6.19 × 10-3 mL/g, indicating poor pore development. In the sandstone samples of the Chang 7 oil layer, the average BET (Brunauer-Emmett-Teller) specific surface area of the Chang 7 Member is 4.252 m2/g, the average total pore volume is 0.018 3 mL/g, and the average maximum pore size is 185.9 nm. The sandstone pores are mainly mesopores, followed by macropores and micropores.
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 Genesis of Granodiorite and Its Implications for Mineralization in Laozuoshan Gold Deposit, Heilongjiang Province: Zircon U-Pb Isotopic Dating and Geochemical Characteristics
Li Yixin, Geng Rui, Xiao Fengli, Bai Chenglin, Sun Jinggui
Journal of Jilin University(Earth Science Edition)    2023, 53 (3): 809-821.   DOI: 10.13278/j.cnki.jjuese.20210405
Abstract863)      PDF(pc) (23174KB)(72)       Save
Laozuoshan gold deposit in Heilongjiang Province is a large-scale gold deposit located in the north-central part of Jiamusi block, Xing-Meng orogenic belt. The ore bodies are closely related to skarn, and hosted in the contacting belt between granodiorite and calcium marble and gneiss schist of Mashan Group, as well as in the ore-controlling structures such as the NW and NWW-trending extensional fractures. The studies of deposit geology, petrography, zircon U-Pb isotope chronology and geochemical characteristics reveal that Laozuoshan gold deposit develops two superimposed mineralization stages, including the skarn-type mineralization in late Middle Permian of Variscan and the hydrothermal mineralization in Yanshan Peried. The skarn-type mineralization during the main metallogenic period is closely related to the granodiorite, and its diagenetic age is (262.6±3.9) Ma. The Variscan granodiorite in this deposit is a kind of weak peraluminous and high potassium calc-alkaline rock series, characterized by high w(SiO2), low Mg# value and MgO, with features of enrichment of large ion lithophile elements and light rare earth elements, while depletion of high field strength elements and heavy rare earth elements, showing the characteristics of I-type granite, and the magma source originates from partial melting of crustal materials. The comprehensive studies show that the Variscan skarn-type mineralization and magmatism occurred during the transition period of the tectonic regime from ocean-continent subduction to continental collision, and the granodiorite is the product of partial melting of crustal materials.
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Zircon Trace Element Geochemical Characteristics of Ore-Bearing Igneous Rocks from Duhuangling High-Sulfidation Epithermal Gold Deposit and Its Geological Significance, Yanji Area, Jilin Province
Chai Peng , Sun Jinggui, Yuan Lingling , Men Lanjing
Journal of Jilin University(Earth Science Edition)    2023, 53 (3): 767-784.   DOI: 10.13278/j.cnki.jjuese.20210331
Abstract862)      PDF(pc) (14596KB)(61)       Save
 Duhuangling gold deposit is one of the high-sulphidation epithermal gold deposits in  Yanji area, northeast China, where a large number of Early Cretaceous igneous rocks are developed. In order to understand the magmatism, magma sources and ore-forming condition of  Duhuangling gold deposit, integrated with the results of previous research, we conducted trace element analyses of zircons from the ore-bearing quartz diorite, granodiorite and granodiorite porphyry in ore district. The majority of zircons possess high Th/U values (>0.1), and their chondrite-normalized REE patterns of all zircons are characterized by HREE enrichment relative to LREE and MREE with distinctive positive Ce and negative Eu anomalies, which are typical of magmatic zircons. All the zircons yield different Ti-in-zircon temperatures, with most zircon crystals between 700 to 900 ℃. Zircon trace elements provide that the ore-bearing rocks were derived from the partial melting of the lower crustal materials and formed in the arc environment related to the plate subduction. In addition, the zircon grains have higher Ce4+/Ce3+ values and lower temperature in the melt of ore-forming granodiorite porphyry than pre-ore rocks, indicating that granodiorite porphyry has high oxygen fugacity, water contents and ore-forming potential. Therefore, the difference in magmatic oxygen fugacity and water contents may be the reasons why the quartz diorite and granodiorite are not mineralized
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Geochemical Characteristics and Source of Crude Oil in Shawan Depression, Junggar Basin

Deng Gaoshan
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 389-412.   DOI: 10.13278/j.cnki.jjuese.20220216
Abstract859)      PDF(pc) (28827KB)(8)       Save
As an important oil and gas enrichment depression in the northwestern margin of Junggar basin, Shawan depression has significant oil and gas discoveries in Hongche fault zone and slope area. In order to clarify the source of crude oil in the structural periphery of Shawan depression, the geochemical indexes of four sets of hydrocarbon source rocks and crude oil in the northwestern margin of Junggar basin were analyzed, and the oil-source correlation was studied using the whole-hydrocarbon geochemistry. It is believed that the crude oil in Shawan depression can be divided into five types with different characteristics in biomarkers and carbon isotopes. Based on the geochemical characteristics of each set of hydrocarbon source rocks, it is considered that the Subtype A1  of crude oil in Shawan depression origins from the high matured source rocks of the Xiawuerhe Formation of Permian, the Subtype A2  of crude oil comes from the normal matured source rocks of the Xiawuerhe Formation, the  Type B of crude oil derives from the intermixture of the products of the source rocks of the Fengcheng Formation and the Xiawuerhe Formation, the  Type C of crude oil originates from the normal to high matured source rocks of the Fengcheng Formation of Permian, and the  Type D of crude oil are the product of the Jurassic source rocks.
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Prediction Method of Hydrocarbon Migration and Accumulation Space Distribution Positions in Different Layers Controlled by Oil Source Faults and Its Application

Xu Fengming
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 461-469.   DOI: 10.13278/j.cnki.jjuese.20220220
Abstract847)      PDF(pc) (5198KB)(6)       Save
In order to study the distribution law of oil and gas near oil source faults in petroliferous basins, based on the study of spatial distribution of oil and gas migration and accumulation in different layers controlled by oil source faults, through the oil source faults transporting favorable positions of oil and gas in the lower reservoir, the spatial distribution position of oil and gas migration and accumulation between source rock and lower cap rock controlled by oil source faults is determined. The spatial distribution of hydrocarbon migration and accumulation between source rock and middle cap rock controlled by oil source faults is determined through the oil source faults transporting favorable parts of oil and gas in the lower reservoir and the leakage parts of regional mudstone caprock in the lower reservoir. The spatial distribution of oil and gas migration and accumulation from the source rock to the upper cap rock controlled by oil source faults is determined by the oil source fault in the favorable part of oil and gas transmission in the lower reservoir and the leakage parts of the lower and central regional mudstone cap rocks. A prediction methods of hydrocarbon migration and accumulation space distribution positions in different layers controlled by oil source faults was established by the combination of the three. The results show that, except the western end, the rest parts are the spatial distribution parts of oil and gas migration and accumulation from the source rock of the Es3 Formation to the caprock of the Es1z Formation controlled by Gangdong fault. The spatial distribution of hydrocarbon migration and accumulation in the source rock of the Es3 Formation and the caprock of the Ed2 Formation, which are controlled by Gangdong fault, are distributed in its middle part, the former is slightly larger than the latter. These position are respectively beneficial to oil and gas generated by the source rock of the Es3 Formation migration and accumulation to the reservoirs under the regional mudstone caprock of the Es1z Formation, the Ed2 Formation and Nm Formation near Gangdong fault, it is consistent with the oil and gas distribution found in the reservoirs under the regional mudstone caprock of the Es1z Formation, the Ed2 Formation and Nm Formation near Gangdong fault at present, indicating that the method is feasible to predict the hydrocarbon migration and accumulation space distribution positions in different layers controlled by oil source faults.
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Volcanic Rock Distribution Based on  Characteristics of Pathway and Magma Chamber:An Example from  Lower Cretaceous Yingcheng Formation in Changling Fault Depression of Songliao Basin 

Hu Jia, Wang Lili, Wang Lixian, Han Haotian, Tao Peng, Tang Huafeng
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 429-446.   DOI: 10.13278/j.cnki.jjuese.20220167
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The distribution pattern of volcanic rocks in a scale of fault depression requires a unified analysis, starting from the deep magma chamber, to the transport system, and then to the eruption and distribution. However, the dominating of individual factor analyses in research process generally leads to an insufficient understanding. To fully understand the spatial distribution of the Lower Cretaceous Yingcheng Formation volcanic rocks in Changling faulted depression, the controlling effects of the magma chamber and ascending pathways are analyzed based on drilling data, seismic data and deep structures. The results are as follows: Laterally, the volcanic rocks of the Yingcheng Formation exhibit characteristics of east-west zonation and north-south blockiness, concentrating in the central depression zone. Horizontal fault throw is a sensitive parameter for determining the development of volcanic rocks, while vertical fault throw has a more significant impact on volcanic rock thickness. Faults are only a necessary condition for the development of volcanic rocks, not a sufficient one. The distribution of volcanic rocks is also constrained by up-doming of the asthenosphere and thinning zones in the crust due to extension. Volcanic material filling corresponds to the basin subsidence center in general. When the volume of volcanic rocks is limited, hydrocarbon source rocks can form a good source-reservoir combination with volcanic rocks. However, when the volume of volcanic rocks is large, it significantly reduces the deposition space for fine-grained sedimentary rocks and limits the spatial extension of hydrocarbon source rocks.


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Mesozoic-Cenozoic Tectonic Transition and Its Significances for Petroleum Exploration in the Southern Jizhong Depression 

Wang Qi, Sun Yonghe, Fu Xiaofei, Zhang Wanfu, Li Xiwei, Wang Yougong, Peng Xianfeng
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 447-460.   DOI: 10.13278/j.cnki.jjuese.20220175
Abstract840)      PDF(pc) (17705KB)(9)       Save

In order to analyze the Mesozoic-Cenozoic tectonic transition and its significance for oil and gas distribution in the southern Jizhong depression, based on seismic data, geological structure characteristics, structure evolution and tectonic transfer of the southern Jizhong depression are analyzed, at the same time, the geological significance for petroleum exploration are discussed. The study shows the differences in the geological structure and evolution on the two sides of the Hengshui accommodation zone (HAZ). The northern part of the HAZ is characterized by a half-graben controlled by double detachment faults with opposite dips, and the southern part of the HAZ is characterized by a compound half-graben controlled by a single detachment fault with multiple faults. The Mesozoic-Cenozoic evolution of the southern Jizhong depression can be divided into the following five periods: basement evolution stage (Mesozoic), initial rift evolution stage (Ek-Es4), strong rift evolution stage (Es3-Es2), weak rift evolution stage (Es1-Ed) and post-rift evolution stage (after Ng). The southern Jizhong depression has experienced a tectonic transition from basement NNE structural systems to Cenozoic NE systems, and the change of the stress field during the Mesozoic to Cenozoic is the dynamic reason for the formation of multi-directional complex structures. The Cenozoic transition affects the distribution of effective source rocks by affecting the migration of troughs, and influences reservoir sand distribution by controlling sand entry channels. The gradient change of displacement of main faults during structural transformation results in transverse anticline forming a favorable position indicating oil and gas enrichment. The transform structures formed by the tectonic transfer in different scales have a certain exploration potential.

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CH4-CO2 Competitive Adsorption and CO2 Sequestration in Na-Montmorillonite  Silt

Gong Fengming, Hou Dali, Qiang Xianyu, Xiang Xueni, Huang Sijing, Han Xin, Yu Yangyang, Gu Kangfu
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 470-478.   DOI: 10.13278/j.cnki.jjuese.20220230
Abstract835)      PDF(pc) (9358KB)(11)       Save

Shale is mainly composed of organic kerogen and inorganic clay minerals, and the adsorption of kerogen and clay minerals on CH4 is the main source of shale adsorbed gas. In order to study the adsorption behavior of CH4, competitive adsorption behavior of CH4-CO2 and the law of CO2 embedding in inorganic clay minerals, using Na-montmorillonite to characterize clay minerals in shale, and using Lammps software to simulate fluid adsorption at different pressures, temperatures and pore sizes based on the grand canonical Monte Carlo method. The results show that with the increase of pressure, the excess adsorption capacity of CH4 increases first and then decreases at each pore size, and reaches a peak value between 11 and 12 MPa. With the increase of temperature, the excess adsorption amount of CH4 decreased gradually at each pore size. With the increase of pore size, the excess adsorption amount of CH4 decreased gradually. At small pore size, CH4 mainly exists in the form of adsorption in Na-montmorillonite, and with the increase of pore size, the adsorption state and the free state of CH4 coexist in Na-montmorillonite, and the action type of Na-montmorillonite on CH4 is physical adsorption. The CO2 displacement efficiency increases with the increase of initial CO2 pressure and pore size. CO2 storage decreases with increasing temperature, increases with increasing injection pressure, and decreases with increasing pore size. The competitive adsorption ratio of CO2 and CH4 decreased with the increase of pressure and increased with the increase of pore size.

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Genetic Mechanism of Relatively High-Quality Reservoirs of Middle Jurassic Shaximiao Formation Tight Sandstone in  Transition Zone Between  Central and Western Sichuan Basin

Song Linke, Liu Sibing, Zeng Qinggao, Zhou Dong, Tang Dahai, Wang Jinxi
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 371-388.   DOI: 10.13278/j.cnki.jjuese.20220208
Abstract815)      PDF(pc) (41013KB)(12)       Save
The Shaximiao Formation in the transition zone between the central and western Sichuan basin has great potential for natural gas exploration, which has become a hot spot of exploration in  Sichuan basin in recent years. At present, there are many aspects restricting the exploration and development of tight sandstone natural gas in the Shaximiao Formation. The formation mechanism and synthesized prediction of “relatively high-quality reservoirs” are one of the key issues that need to be resolved urgently. In this paper, a series of analysis methods were performed, including systematic physical property analysis, blue-dye thin section identification, scanning electron microscopy analysis, and reservoir geochemical analysis, to determine the genetic mechanism of relatively high-quality reservoirs in the Shaximiao Formation. The results indicate that the tight Shaximiao sandstones are dominated by lithic feldspar sandstone and feldspar lithic sandstone. The average volume fraction of quartz,feldspar,and rock debris in the Second Member of the Shaximiao Formation (SMSF) are 35.27%,  35.37%, and 29.36% respectively. The average volume fraction of quartz,feldspar,and rock debris in the First Member of the Shaximiao Formation (FMSM) are 37.79%, 24.01%, and 38.20% respectively. The volume fraction of feldspar is relatively high compared to the FMSM,and the volume fraction of rock debris is relatively high compared to the SMSF. In terms of type and content of lithic fragments, sandstones in the SMSF are dominated by metamorphic fragments, accounting for 55% of the whole lithic fragments. By contrast, those in the FMSF are dominated by magmatic fragments, making up to 43% of the whole lithic fragments. In addition, the reservoir pore system is predominately composed of primary pores followed by feldspar dissolution pores, in which the FMSF is characterized by a higher content of those pores than the SMSF. In the SMSF, samples with porosity above 12%  account for 38.00%, but with permeability above 1×10-3μm2 account for 25.25%. Those values in the FMSF are 3.09% and 41.22%, respectively. It is generally reflected that some relatively high-quality reservoirs tend to be developed under a tight background. The fact, that the SMSF reservoir is characterized by better porosity and the FMSF has better permeability, demonstrates that the pore structure of the FMSF reservoir is relatively better. Besides, The tight sandstone reservoir in Shaximiao Formation is controlled by litho-mineral association, hydrocarbon source system and diagenetic system. The litho-mineral association provided a material basis for the diagenetic evolution. The hydrocarbon source system controlled the dissolution intensity, and provided ions for main authigenic minerals precipitation in sandstone. The opening degree of the diagenetic system had an effect on the ions’ in-and-out, and affected the dissolution and precipitation of the diagenetic products. The difference of litho-mineral association, variation of sedimentary environment, hydrocarbon source system and opening degree of diagenetic system in SMSF and FMSF are the main reasons for the differential diagenesis.
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1203-.  
Abstract525)      PDF(pc) (14784KB)(145)       Save
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1174-.  
Abstract512)      PDF(pc) (33769KB)(36)       Save
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1127-.  
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1091-.  
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1348-.  
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1360-.  
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1328-.  
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1302-.  
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1275-.  
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1107-.  
Abstract432)      PDF(pc) (45259KB)(55)       Save
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1369-.  
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1286-.  
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1234-.  
Abstract416)      PDF(pc) (12229KB)(70)       Save
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1265-.  
Abstract412)      PDF(pc) (5380KB)(53)       Save
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1338-.  
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1223-.  
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1153-.  
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1314-.  
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1255-.  
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1215-.  
Abstract312)      PDF(pc) (4072KB)(48)       Save
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Remote Sensing Image Target Detection Algorithm Based on Improved YOLOX
Li Meilin, Rui Jie, Jin Fei, Liu Zhi, Lin Yuzhun
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1313-1322.   DOI: 10.13278/j.cnki.jjuese.20220197
Abstract271)      PDF(pc) (13416KB)(324)       Save
Target detection is a fundamental and routine task in remote sensing image processing. In this paper, we design a target detection algorithm for remote sensing images based on the YOLOX network. Firstly, ASFF is added to the feature extraction module PANet to deeply mine the fine features with inconsistent scale in target detection. Secondly, an ECA-based feature extraction module is designed with efficient channel interaction to reduce the complexity of the model while paying more attention to the positive sample feature information in the feature map. Then, to avoid the problem of gradient disappearance and weak activation effect caused by overfitting, the use of swish activation function is proposed. Finally, experiments are conducted on DOTA to verify the best mechanism and effectiveness of the improved method through qualitative analyses of the ablation experiments and quantitative comparison experiments. With the addition of ASFF and ECA mechanisms and the optimization of the swish activation function, the improved network model achieves an mAP of 74.42%, an improvement of 12.75% over the original network. Compared with the current widely used target detection algorithms Mobilenet-YOLOv4, YOLOv4, YOLOv5 and YOLOX, the proposed  algorithm achieves an improvement of 11.42%-17.84% in mAP accuracy.
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Frequency Division Compression Technology of Prestack Seismic Data Based on EZW Algorithm
Yan Haiyang, Zhou Hui, Liu Haibo, Xu Zhaohong, Sun Zandong, Liu Zhao, Luo Minxue
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1238-1238.   DOI: 10.13278/j.cnki.jjuese.20230010
Abstract265)      PDF(pc) (28797KB)(175)       Save
With the significant improvement of high-density acquisition and daily acquisition efficiency, the amount of exploration data is growing exponentially. In order to save storage space and improve transmission efficiency, the research on high-fidelity compression and reconstruction of prestack seismic data is extremely urgent. EZW (embedded zerotree wavelet) algorithm has excellent compression performance. The traditional EZW algorithm for seismic data compression is based on data in the t-x domain. Because the wavenumber of prestack seismic data is wide and the frequency band is limited, the energy of the discrete cosine transform (DCT) data is mainly concentrated in the low-frequency in the DCT domain. This paper proposes a frequency division seismic data compression technology. Firstly, 2D-DCT is performed on the t-x data, and then frequency division is applied to the 2D-DCT data to obtain high-frequency and low-frequency data. By separately coding high-frequency and low-frequency data based on EZW, the low-frequency data has a high coding level to ensure the signal-to-noise ratio (SNR) of the reconstructed data, and the high-frequency data has a low coding level to improve the data compression ratio (CR). The synthetic data and field data experiments show that the compression ratio with the proposed method is higher than that with the conventional EZW at the same SNR.
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1037-.  
Abstract260)      PDF(pc) (37528KB)(52)       Save


1.中国石油西南油气田公司勘探开发研究院,成都610041

2.油气藏地质及开发工程国家重点实验室(成都理工大学),成都610059

 

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Possible Problems of Groundwater Evrionment  in the Exploitation of Geothermal Energy
Xu Tianfu, Chen Jingyi, Feng Bo, Jiang Zhenjiao
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1149-1162.   DOI: 10.13278/j.cnki.jjuese.20210382
Abstract229)      PDF(pc) (5927KB)(335)       Save
Geothermal energy exploitation and utilization are closely related to groundwater transport and the evolution of water environment. In this study, wereviewed the development status and typical mining technologies for the shallow geothermal energy stored in the soil and phreatic aquifers, median-to-high-temperature geothermal energy in deep aquifers, and high-temperature geothermal energy stored in the hot dry rocks for informational purposes of sustainable development and utilization of large-scale geothermal resources. In particular, the shallow geothermal energy can be classified into ground source heat pump and ground water heat pump according to the subsurface heat source; Median-to-high-temperature geothermal energy can be exploited mainly by direct mining, combination of production and injection and standing column well system; And high-temperature geothermal energy can be exploited using enhanced geothermal systems (EGS) through reservoir reconstruction technique such as hydraulic fracturing or chemical stimulation. Furthermore, the potential impact of geothermal energy exploitation on the groundwater resources was analyzed and summarized following the reported site cases, mainly focused on the cold and heat accumulation brought by heat pump technology, the decline of groundwater level caused by hydrothermal exploitation and the possibility of microseismic events or fracturing fluid leakage caused by hydraulic fracturing of hot dry rocks. In the end, the approaches were proposed to promote the sustainable development of geothermal resources and reduce the negative impacts on groundwater resources, including improving the recharge capacity, maintaining the water balance in the process of mining and irrigation, maintaining the heat exchange efficiency and the re-balance of underground heat, and adopting new materials. 
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Numerical Simulation and Dispersion Characteristics Analysis of Crack Model Wavefield Based on Peridynamic Theory
Zuo Pengfei, Liu Cai, Guo Zhiqi, Feng Xuan
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1250-1261.   DOI: 10.13278/j.cnki.jjuese.20220221
Abstract165)      PDF(pc) (5044KB)(104)       Save
Peridynamic theory uses integral form of motion equations, which can effectively avoid the problem that the spatial partial derivative does not exist. It is widely used in simulating discontinuous problems such as crack propagation and fracture damage in different material models. However, there are few studies on wave propagation and dispersion characteristics in peridynamic theory model. In order to study the propagation law of waves in peridynamic theory model, in the case of plane stress, the equations of motion in integral form are established, and the wavefield numerical simulation of isotropic plate model and plate model with parallel cracks are carried out, and the wavefields of longitudinal and shear waves in the classical continuum theory are compared and analyzed. Based on motion equations of ordinary state-based peridynamic theory, the dispersion relations for 1D and 2D are derived in detail. The influences of peridynamic parameters such as the number of material point, the radius of the horizon and the shape parameter on the dispersion curves are comprehensively discussed. In wavefield numerical simulation, the wavefield numerical simulation results of the linear peridynamic solid (LPS) model and the linear elastic solid of the classical continuum theory are in good agreement. The existence of cracks in the model will cause reflection and diffraction of waves during propagation. In the analysis of dispersion characteristics, the dispersion characteristics of LPS model are more consistent with those of the classical continuum model when the  radius of the horizon is smaller and the  shape parameter is larger.
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Geochemical Characteristics of Source Rocks and Oil Origins of Jiufengshan Formation in Southern Depression of Dayangshu Basin
Fu Li
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1001-1015.   DOI: 10.13278/j.cnki.jjuese.20220104
Abstract150)      PDF(pc) (11207KB)(274)       Save
Dayangshu basin is a Late Mesozoic residual basin with a low degree of exploration and research. It shows a good exploration prospect with the industrial oil flows obtained from several wells in recent years in the southern depression. A systematic understanding of the source rocks and the hydrocarbon origin of Jiufengshan Formation is still uncertain. Based on the geochemical analysis data of source rocks and crude oils, including TOC、Rock-Eval、GC-MS, and carbon isotope, the hydrocarbon generation potential of source rocks of Jiufengshan formation are evaluated, the properties of crude oils and oil source are studied. The results show that medium-good source rocks are developed in the first member (K1j1) and the third member(K1j3) of Jiufengshan Formation, with w(TOC) of 1.76% and 2.59%, w( S1 + S2) of 4.44 mg/g and 7.36 mg/g, bitumen of 0.21% and 0.09% respectively. The organic matter type of the K1j1 is mainly type Ⅱ1 including some typeⅠ, K1j3 is mainly type Ⅱ1 including some typeⅡ2, and the vitrinite reflectance (Ro) of the source rocks in K1j1 is mainly 0.70% to 1.60%, at the mature to high mature evolution stage. Ro in K1j3 is mainly from 0.50% to 1.10% and at the mature evolution stage. The hydrocarbon generation threshold of the source rock is about 1 300 m, and the hydrocarbon generation peak is about 1 750 m. The source rock has the characteristics of early hydrocarbon generation. The crude oils are light to medium, characterized by high viscosity, high wax, low sulfur, and high saturated hydrocarbon. The crude oil enriches light carbon isotope with δ13Coil from -30.40‰ to -29.38‰, δ13C sat from -30.78‰ to -29.07‰, and δ13Caro from -29.73‰ to -27.91‰, which indicates the source of lacustrine algae. The main peaks of alkane in oil are nC19 and nC21, OEP is 1.07 to 1.08, and Pr / Ph is 0.83 to 1.10. The crude oil can be divided into two groups based on terpenoid steroid marker. Group one includes the crude oil of Wells YC1 and Y3, with relatively high tricyclic terpane, C30D, Ts/Tm, C29Ts/C29 hopane, sterane C27R/C29R, regular sterane / hopane, rearranged sterane / regular sterane, C2920S / 20 (S+R), C29ββ/(ββ++αα) and low β-carotene. Group two includes the crude oil of Well YX4 and Well Y6, with high β-carotene and relatively low sterane terpane ratios, indicating that the maturity of Well YC1 and Well Y3 oil is higher than that of Well YX4 and Well Y6, and there are slight differences in sedimentary environment and parent material source. The oil and rock correlation of biomarkers shows that the crude oil of Wells YC1 and Y3 mainly comes from the source rock of K1j1, and the crude oil of YX4 and Y6 wells mainly comes from the source rock of K1j3. The potential hydrocarbon accumulations in this area are source-reservoir integrated accumulations and lower source rocks generation-upward migration accumulations.
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Powdered Activated Charcoal Enhanced the Removal of Iron and Manganese by Ozone Oxidation
Zhang Shaojie, Liu Shibo, Yang Wu, Chen Siqi
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1228-1237.   DOI: 10.13278/j.cnki.jjuese.20210369
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In order to effectively solve the problem of iron and manganese overload in groundwater, this paper proposes a new method of removing iron and manganese by combining powdered activated carbon (PAC) and ozone, and explores the mechanism of the effect of PAC in treating iron and manganese in water by ozone oxidation. The effect of PAC and ozone on the treatment of Fe and Mn alone was firstly investigated; Then the effect of PAC and ozone on the treatment of Fe and Mn in combination was investigated, and the effect of different conditions (pH, temperature, PAC dosage, and oxidant concentration) on the removal of Fe and Mn in water was investigated; Finally, the mechanism of the effect of PAC on the treatment of Fe and Mn in ozone oxidation water was investigated. The results showed that PAC could enhance the oxidation of Fe and Mn by ozone under different conditions. Under the conditions of PAC dosage of 0.3 g/L, ozone mass concentration of 5 mg/L, pH of 7.0, and room temperature, the mass concentration of Fe and Mn mixed solution rapidly decreased from 0.5 mg/L to 0.1 mg/L within 5 min, which met the requirements of corresponding emission standards; With the increase of PAC dosage, the residual concentrations of Fe and Mn gradually decreased, which indicated that the reaction was highly dependent on the active sites on the surface of PAC, further confirming the effect of PAC on the removal of Fe and Mn from water. The characterization results such as scanning electron microscopy (SEM) and Mapping analysis showed that the reaction formed iron oxide and manganese oxide coatings on the surface of PAC, and these oxide coatings would further accelerate the removal of free iron and manganese from water.
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Mineralization Potential Analysis of Sandstone-Type Uranium Deposits in Northern Songliao Basin
Li Yan, Nie Fengjun, Wang Dongxu, Jia Licheng, Lu Shengjun, Yan Zhaobin, Luo Min, Liu Xiaohui
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1075-1089.   DOI: 10.13278/j.cnki.jjuese.20210194
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 A lot of geological work has been carried out in the prospecting for sandstone-type uranium deposits in the southern Songliao basin, resulting in significant achievements. In contrast, the geological exploration work for uranium deposits in the northern Songliao basin is currently inadequate. In this paper, based on the analysis of uranium mineralization conditions, such as uranium-bearing rocks, basin tectonic evolution, paleoclimate, stratigraphic evolution, distribution of sedimentary facies, development of sand bodies and epigenetic reformation, etc., the mineralization potential of sandstone-type uranium deposits in the northern Songliao basin is comprehensively evaluated, and its prospecting direction is discussed. The northern Songliao basin is rich in uranium sources and has good metallogenic conditions. Since the Cretaceous, the basin has experienced four periods of tectonic inversion, forming two main uranium prospecting targets, Upper Cretaceous Yaojia Formation and Sifangtai Formation. Inside the basin, the Yaojia and Sifangtai Formations have well-developed sedimentary facies and sandbody conditions, and the oxidation is noticeable in some areas, and the oxidation zone and uranium mineralization are also relatively developed, providing important clues for ore prospecting. Comprehensive analysis shows that the overall uranium metallogenic conditions are good in the northern Songliao basin, with the Yaojia Formation being the key prospecting strata in the eastern section, and the Sifangtai Formation in the western section. The ore exploration type is interlayer oxidation zone type.
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Extraction Method of Alternation Anomaly Information Based on Remote Sensing Prospecting in the Jianbian Farm Area, Heilongjiang Province
Zhao Zhonghai, Qiao Kai, Sun Jinggui, Chen Jun, Cui Xiaomeng, Liang Shanshan, Manirambona Alain Jospin
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1275-1275.   DOI: 10.13278/j.cnki.jjuese.20210046
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The Jianbian farm area in Heilongjiang Province is located at the intersection of the Great and Lesser Xing’an Ranges. The multi-stage magmatic and tectonic evolution history in this area has resulted in a complex and diverse geological background for mineralization. Based on the interpretation of Landsat ETM image data in the Jianbian farm area of Heilongjiang, this paper combined the mineral spectral characteristics and the basic geological data, and used the method system of “de-interference, principal component analysis, and ratio method combined with anomaly screening” to extract the mineralized alteration information, such as iron staining and hydroxylation in the study area. Thirteen hydroxyl mineralization alteration anomalies and seventeen iron-stained mineralization alteration anomalies were identified. The mineralized alteration anomalies were mainly found in Cretaceous volcanic strata and were mainly distributed along the intersection of NE- and NW-trending faults, NNW- and SN-trending faults. They were closely related to the contact zone of Mesozoic volcanic rocks and Early Cretaceous-Early Carboniferous intrusive rocks. Combining the known geological and mineral data and field verification results, it is found that iron-stained anomalous minerals such as limonite and hematite, as well as anomalous hydroxyl minerals such as carbonation and chloritization, were commonly developed in this area. The extracted iron-stained and hydroxyl mineralized alteration anomalies closely matched physical and chemical exploration anomalies, and were highly consistent with known Au, Cu and Mo occurrences and mineralized occurrences. This provides a theoretical basis and direction for the next step of mineral exploration in the study area.
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Thickness Prediction of Reservoir Effective Sand Body by Deep Fully Connected Neural Network
He Ting, Zhou Ning, Wu Xiaoyu
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1262-1274.   DOI: 10.13278/j.cnki.jjuese.20220143
Abstract138)      PDF(pc) (17189KB)(176)       Save
Channel sand is one of the important oil and gas reservoirs. The quantitative prediction of sand body thickness is the key to improve the efficiency of oil and gas development. With the enhancement of non-homogeneity of target reservoir, the relationship between seismic attribute and reservoir lithology, physical property and pore fluid becomes more complicated. How to achieve efficient and intelligent quantitative prediction of complex reservoirs under the condition of limited geological information is currently a hot and difficult topic in the field of reservoir prediction. To achieve high accuracy and intelligent prediction of the tight sandstone reservoir, a reservoir effective sand thickness prediction method based on deep fully connected neural network is proposed in this paper. The method constructs a multilayer stacked fully connected neural network to optimize the seismic attributes predicted for the effective sand thickness of the reservoir layer by layer, and maps the optimized attributes directly to the sand thickness. We first analyze the influence of training samples on fully connected neural network modeling, and then compare the performance of the deep and shallow morphology of this network in the case of small samples when the model size is larger than the number of training samples and the model size is smaller than the number of training samples, and find that the deep network outperforms the shallow one when the training samples are small, provided that the number of training samples is larger than the model size. Finally, we apply the deep fully connected neural network to the effective sand body thickness prediction from real data of Shengli oilfield, and the application results show that the method achieves effective identification of sand bodies around 4 m in a tight sandstone reservoir, reflecting the ability of this end-to-end intelligent modeling method to mine latent geological information from seismic attributes, thus confirming its effectiveness in quantitative reservoir prediction.
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Karst Rocky Desertification Mapping and Causes Analysis Based on Sentinel-2A Imagery
Xi Jing, Jiang Qigang, Liu Huaxin, Gao Xin
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1301-1312.   DOI: 10.13278/j.cnki.jjuese.20220239
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Karst rocky desertification is one of the serious ecological and environmental problems in Southwest China. As the inheritance and continuation of Landsat and SPOT (systeme probatoire d’observation de la terre) series satellite data, Sentinel data has better application prospect in ecological and environmental monitoring. By the traditional method, the Karst rocky desertification mapping extracted from Sentinel-2A is only at 20 m resolution and this method wastes the detailed information. In order to extract the Karst rocky desertification more accurately, this research constructs 10  m resolution rocky desertification index for rocky desertification mapping of Beimen River basin in Wenshan, Yunnan based on the characteristic of Sentinel-2A data and analyzes the geological causes. By comparing four fusion algorithms, à trous wavelet transform has the better effect than high pass filtering, principal component analysis and  Gram-Schmidt transform  in short-wave infrared band (B12). The results show that the 10 m  normalized differential rocky index (NDRI) and rock exposure rate (fr )  have good correlation with 20 m NDRI and fr (the correction coefficients are 0.90 and 0.81, respectively), and they can provide more information of different ground objects. It indicated that the 10 m resolution index of Sentinel-2A has better performance for Karst rocky desertification mapping in this study.  The geological causes analysis of Karst rocky desertification in  Beimen River basin shows that the Karst rocky desertification mainly consists of  potential Karst rocky desertification and light Karst rocky desertification, which account for  40.66% and 16.97% of the total  basin area.  Karst rocky desertification is distributed mostly in the Gejiu  Formation and Banna  Formation. Within slope range of 0°-25°, all types of Karst rocky desertification are concentrated development , accounting  for 82.71% of the total area of Karst rocky desertification. 
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Zircon U-Pb-Hf Isotopic Compositions and Their Geological Significance of Early Devonian Granites in Wenquan, Xinjiang
Jia Yinggang, Zhao Jun, Guan Liwei, Duguer Weiwei, Chen Youxin, Chen Jian
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1132-1148.   DOI: 10.13278/j.cnki.jjuese.20210358
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There are numerous Late Paleozoic acidic intrusive rocks in Wenquan area, which is located on the northern margin of the Yili block. In this paper, we present new zircon U-Pb geochronology, Lu-Hf isotopic and geochemical studies of the Early Devonian granites from Wenquan area, aiming to confirm their timing, discuss their petrogenesis, and explore their tectonic evolution process. The zircon LA-ICP-MS U-Pb age of the monzogranites is (418±7) Ma which indicates that their crystallization age is the product of Early Devonian magmatic activity. Meanwhile, the zircon Hf isotope compositions of the monzogranite are typically characterized by high εHf(t) values (8.2-14.0, with an average of 11.3), and the young two-stage model ages (TDM2=863-492 Ma), implying their derivation from a relatively juvenile crust. These two types of granites are characterized by high SiO2, weakly peraluminous, as well as low CaO and MgO contents. The trace elements of the granites are characterized by depletion in high field strength elements (Nb, Ti, P), and enrichment in large ion lithophile elements (K, Rb). The standardized distribution pattern of rare earth elements in chondrites is enriched in light rare earth elements and depleted in heavy rare earth elements, with significant negative Eu anomalies. The low zircon saturation temperature, negative correlation between P2O5 and SiO2, and other geochemical features suggest the granites are I-type granites. Several tectonic discrimination diagrams shows that they were formed in a continental magmatic arc setting. Combined with the regional tectonic background and the evolution information of magmatic rocks in the adjacent area, it is speculated that the granites were mainly derived from the crustal accretion in response to subduction of the Junggar-Balkhash Ocean. 
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Complex Structural Characteristics and Evolution of Magmatic Diapirism Reformed Subsag: A Case of Lufeng 22 Subsag, Pearl River Mouth Basin
Wu Qiongling, Peng Guangrong, Xiao Zhangbo, Lei Yongchang, Shen Mengrong, Qiu Xinwei, Li Min
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1048-1065.   DOI: 10.13278/j.cnki.jjuese.20230001
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The Lufeng 22 subsag is a magmatic diapir reformed subsag in Dongsha uplift,Pearl River Mouth basin. In order to clarify the structural deformation characteristics and evolution process of such kind of subsag, the research reconstructed the evolution process of the study area based on the structural interpretation of seismic data, the analysis of residual stratum thickness, and the balanced profile technology. it is found that, The west slope and the east sub-depression of Lufeng 22 subsag was subjected to three stages of strong magmatic diapirism, and the most active diapri is in member 4 of Wenchang Formation. The effect of magma diapirism on the depression structure is mainly shown in three aspects. First, magma diapir destroyed the initial structural style of the subsag, caused the boundary fault to bend and even break, showed a characteristics of plane zoning; Second, the strong uplift of magma lead to the strong tilting of the strata, thus the gentle slope strata was greatly uplifted and subjected to strong denudation; Third, the magma diapir produced secondary bulge, which influenced the location, scale and evolution of the sedimentary center, thus showed a very complex structural characteristics and evolution process. The west slope and eastern subsag with strong magmatic diapirism only experienced evolution stages of fault-down thrown basin and faulted-sag basin, while the western subsag, high-in-sag and east slope with weak magmatic diapirism completely developed three evolution stages of fault-down thrown basin, faulted-sag basin and sag basin. The tectonic units showed lateral zoning characteristics.
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1065-.  
Abstract127)      PDF(pc) (9962KB)(59)       Save
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Determination Method of Oil-Source Fault Transporting Oil and Gas Evolution Stage and Its Application
He Chunbo, Zhang Yaxiong, Yu Yinghua, Yuan Hongqi
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1066-1074.   DOI: 10.13278/j.cnki.jjuese.20230018
Abstract125)      PDF(pc) (7656KB)(148)       Save
In order to study the law of hydrocarbon enrichment at the oil-source fault in the petroliferous basin, based on the study on the conditions and evolution stage of oil-source fault transport, the method of determining the evolution stage of oil-source fault transport is established by determining the activity period of oil-source fault and the formation period of the oil-source fault transport in the oil source and the oil source outside the oil transfer station. The method is used to determine the evolution stage of oil and gas transport from Nandagang fault to the Lower Member of the Shahejie Formation in Qikou sag, Bohai Bay basin. The results show that, the oil and gas stage of Nandagang fault to the Lower Member of the Shahejie Formation to the Third Member of the Shahejie internal transfer station starts from the deposition of Guantao Formation to the middle deposition of Minghuazhen Formation; The oil and gas stage of the transfer station of the third stage is from the middle deposition to the end of the Minghuazhen Formation. After two evolutionary stages, the oil and gas transporting period is relatively long, which is conducive to the large-scale accumulation and accumulation of oil and gas from the underlying source rocks of the Third Member of the Shahejie Formation in the Lower Member of the Shahejie Formation. According to the method of this paper, it can reasonably explain the phenomenon of oil and gas enrichment in the lower sub-member of the Nandagang fault. This method is suitable for determining the evolution stage of oil and gas transport by oil-source faults.
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Experiment on Concrete Building Erosion by Underground Water in Gypsum Rock Formation
Wang Fugang, Pan Huilin, Li Shengwei, Wang Donghui, Wu Mingjie, Ping Shifei, Cao Yuqing
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1185-1194.   DOI: 10.13278/j.cnki.jjuese.20220042
Abstract124)      PDF(pc) (5833KB)(100)       Save
During underground engineering construction in gypsum-enriched formations, the reaction between  gypsum and groundwater leads to the dissolution of Ca2+ and SO42-, which enhances the erosion effect on the concrete foundation of underground structures and affects the safety of underground engineering. In order to investigate the erosion characteristics and mechanisms of concrete under different  formation environmental conditions, commonly used C20 and C30 concrete in underground engineering construction were studied. The study focused on the gypsum-containing formation  conditions in the southern part of Chengdu basin and explored the erosion characteristics and mechanisms of concrete in both gypsum-containing and non-gypsum-containing formations under changing underground temperature conditions. The results show that: 1) The erosion degree of C20 and C30 concrete in gypsum-containing formations is significantly greater than in non-gypsum-containing formations. Under the erosionby different geological groundwater, the  maximum mass change rates of C20 and C30 concrete are 1.80% and 0.87%, with the maximum compressive strength reduction rates of 20.14% and 12.80%, respectively. C30 concrete exhibits a smaller attenuation in compressive strength under different groundwater conditions, making it more suitable as a construction material for underground engineering. 2) Increasing temperature enhances the erosion effect of SO42- on concrete, leading to a decrease in compressive strength. Among them, the maximum compressive strength reduction rates of C20 concrete under Quaternary and Guankou  Formation groundwater erosion reach 6.89% and 3.89%, respectively. 3) Concrete erosion occurs from the outside to the inside, where Ca2+ and SO42- in groundwater recrystallize to form gypsum on the  external surfaces of the concrete and then diffuse along cracks towards the interior, resulting in the formation of ettringite crystals, expansion forces, crack formation, and a decrease in compressive strength. Through correlation analysis, a relationship equation between the mechanical properties of concrete and temperature was established, achieving quantitative calculation of long-term changes in the mechanical properties of concrete in gypsum-containing formation engineering construction.
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Prediction of Dry-Hot Rock Targets with Multivariate Information in Guide Basin Based on Remote Sensing Technology
Yan Baizhong, Li Yao, Qin Guangxiong, Yu Kaining, Wu Yunxia , Wang Yanan
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1288-1300.   DOI: 10.13278/j.cnki.jjuese.20220215
Abstract122)      PDF(pc) (17171KB)(150)       Save
Using Landsat 8 TIRS thermal infrared data, the surface temperature of Guide basin was identified by remote sensing through single window algorithm and split window algorithm, and the location of high temperature anomaly area was determined. Based on the formation conditions of dry hot rock, a multi information dry hot rock target prediction model including 12 factors, including strata, rock mass, faults, annular structure, linear structure, hydrothermal alteration anomaly, surface temperature anomaly, hot spring, geothermal drilling, regional gravity anomaly, regional aeromagnetic anomaly, and electromagnetic exploration information, was constructed, and the dry hot rock target in Guide basin was predicted. The results show that: 1) The Neogene, Triassic and Quaternary strata are the heat preservation covers of the dry hot rocks in Guide basin, the large NW trending Late Triassic intermediate acid concealed granite is the heat storage rock mass, the NNW trending Waligong Mountain deep fault and granite body are the heat conduction channels, the lower mantle asthenosphere heating and the partially molten layer heating are the main heat sources, and the rock radioactive heat generation is the superposition heat source. 2) The concealed rock mass prediction area, surface temperature anomaly area and hydrothermal alteration anomaly area in the basin all have the characteristics of distribution along the northwest southeast direction, and the distribution positions confirm each other. 3) According to the model, there is a large dry hot rock belt distributed along the northwest southeast direction in guide basin, with an area of about 820 km2. 
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Genesis of Early Permian Volcanic Rocks in Yitong Area, Central Jilin Province: Constraints from Zircon U-Pb Geochronology and Whole-Rock Geochemistry
Mu Ruiting, Pei Fuping, Shi Yuqin, Wei Jingyang
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1117-1131.   DOI: 10.13278/j.cnki.jjuese.20220114
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The volcanic rocks in the Yitong area of central Jilin Province are located in the eastern segment of the northern margin of the North China plate. This paper presents zircon LA-ICP-MS U-Pb geochronology and geochemical data of the volcanic rocks in this area, aiming to explore their petrogenesis. The zircons in the andesite present euhedral-subhedral, and obvious magmatic oscillation zone, with Th/U ratios of 0.06-0.95, indicating their magmatic origin. Zircon dating results indicate that basaltic andesites were formed at (285±2) Ma, the Early Permian. The rock assemblage of the Early Permian volcanic rocks is basaltic andesite and andesite. The SiO2 mass fraction of the samples is 51.29%-58.91%, and the Mg# values are 39-66, belonging to the tholeiitic series, relatively enriched in light rare earth elements (LREEs), large ion lithophile elements (LILEs), and depleted in high field strength elements (HFSEs). Comprehensive studies suggest that the Early Permian volcanic magma originated from the depleted mantle wedge metasomatized by subducting fluids, and was formed in the active continental margin environment of the southward subduction of the Paleo-Asian Ocean. Combined with regional research results, it is believed that the northern margin of the North China plate was under the southward subduction of the Paleo-Asian Ocean in the Early Permian.
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Characteristics and Mechanism of Shear Strength Variation with Time of Cohesive Soil Layers in Chongming Dongtan Reclamation Area
Wang Qing, Lü Zuojun, Yao Meng, Dong Jiaqi, Xia Weitong, Yang Tianliang, Niu Cencen
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1163-1163.   DOI: 10.13278/j.cnki.jjuese.20220011
Abstract118)      PDF(pc) (12624KB)(133)       Save
Abstract: To carry out engineering geological evaluation of hydraulic reclamation areas such as Chongming Dongtan, this paper aims at the change in shear strength of the underlying clayey soil layers in Chongming Dongtan. Considering different reclamation times, soil samples from boreholes in five different reclamation areas (within the 1949 cofferdam, 1949-1964, 1964-1976, 1976-1990, and 1990-1998) were selected for direct shear tests, and the variation of shear strength of soils in different periods and layers were analyzed.  Moreover, the microstructure of the soil samples was observed by scanning electron microscopy, and the change in shear strength was analyzed qualitatively and quantitatively from a microscopic perspective. The results revealed that: 1) The shear strength of the clayey layer varied as, the clay layer in the 1949-1964 reclamation zone had the largestshear strength, and the peak shear stress at 50, 100, 200, and 300 kPa is 33.31, 46.68, 102.10 and 147.15 kPa, respectively. Little difference in shear strength between boreholes in silty clay layer was observed under various levels of vertical pressure. From west to east, the shear strength indexes of the clay layer showed an opposite trend to that of the silty clay layer, in relation to the trend in natural water content. 2) From west to east, significant changes in the microstructure of the soil samples were observed. The soil microstructure in clay layer changed from a flocculent/aggregate to a matrix structure, and the soil microstructure in silty clay layer gradually transitioned from a skeletal/aggregate structure to a matrix structure and to a flocculent/aggregate structure. 3)  The average pore diameter of the particle was negatively related to the cohesion and positively related to internal friction angle. In addition, the average shape coefficient of the particle was positively related to the cohesion and negatively related to internal friction angle. This indicated that average pore diameter  and the average shape coefficient of the particles were directly related to the shear strength indexes of the soil.
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Enrichment Characteristics of Coalbed Methane and Optimization of Favorable Areas in Qitaihe Fault Depression, Boli Basin
Zhang Xiaoqing, Kang Yuguo, Sun Bin, Sun Qinping, Yang Qing
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1033-1047.   DOI: 10.13278/j.cnki.jjuese.20220058
Abstract117)      PDF(pc) (18875KB)(181)       Save
The Qitaihe fault depression in the Boli basin is rich in coalbed methane resources, but the exploration level is low, and the understanding of the enrichment and accumulation laws and mechanisms is insufficient, which restricts exploration practice. Based on a detailed dissection of the geological conditions of coalbed methane in the Qitaihe fault depression, this article reveals the enrichment characteristics and reservoir formation mechanism of coalbed methane in the study area. The study found that the coalbed methane reservoir in the Qitaihe fault depression has good conditions, with many coal seams in the Lower Cretaceous Chengzihe Formation, a large total thickness of coal seams, multiple developed coal rich centers, and a high degree of thermal evolution. The physical properties of coal reservoirs are favorable, and the gas content of coal seams is generally characterized by high in the west and low in the east. The structure, the hydrology,  the sealing and other preservation conditions benefit coalbed methane reservoir formation. There are three types of models of coalbed methane reservoir formation, syncline-hydraulic sealing, fault sealing-hydraulic sealing, and fault-multi seam self-sealing. Under moderate burial depth and slow stagnant water environment, the reverse fault sealing area, secondary structural high point, and middle coal seam stratification are favorable locations for coalbed methane enrichment. On this basis, a multi-level fuzzy mathematics evaluation model for coalbed methane selection was established, and favorable areas were evaluated. Seven coalbed methane favorable areas were selected, including Qinglongshan-Taoshan district and Machang district.
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Step-Like Landslide Displacement Prediction Based on Multi-Factor and Multi-Scale Analysis
Xiong Chao, Sun Hongyue
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1175-1184.   DOI: 10.13278/j.cnki.jjuese.20210403
Abstract112)      PDF(pc) (9349KB)(194)       Save
In order to quantitatively analyze the time-lag effect between displacement and inducing factors of step-like landslide, as well as to improve the accuracy of displacement prediction, in this study, the authors proposed a new prediction model and conducted comparative analysis. First, the cumulative displacement was separated into trend term and periodic term based on time series analysis. Then, using maximum information coefficient (Cmi) and multivariate empirical mode decomposition (MEMD) for multi-factor analysis and multi-scale analysis, the multi-factor and multi-scale MEMD prediction model was constructed. Finally, taking  Bazimen landslide in  Three Gorges Reservoir area as an example, the optimal lag period inducing factors were selected as the model input through Cmi, and multi-scale prediction model was established based on the decomposition of multivariate sequence by MEMD. The proposed model was compared with other models (single-factor and single-scale model, multi-factor and single-scale model, single-factor and multi-scale EMD model). The results showed that the optimal lag periods of rainfall and reservoir water level in  Bazimen landslide were 2 d and 4 d. After decomposing the landslide multivariate sequence by MEMD, three groups of mode functions were obtained, each group had seven components, and the time-scale of each corresponding component was consistent. The response of the periodic term displacement to the inducing factors had a time multi-scale characteristic. Compared with the comparison model, the root mean square error of the multi-factor and multi-scale MEMD prediction model decreased by 49.4%, 36.9% and 27.4% on average, and the mean absolute percentage error decreased by 38.0%, 26.4% and 15.8% on average.
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Geochemistry and Geological Significance of the Two Episodes of Anatectic Garnet Granites in the Khondalite Belt, Northern Margin of the North China Craton
Shi Qiang, Li Chen, Zhou Yuxin, Gao Xin, Li Huixuan, Ma Renwen, Xu Yan, Zhao Zhonghai, Xu Zhongyuan
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1090-1116.   DOI: 10.13278/j.cnki.jjuese.20220321
Abstract109)      PDF(pc) (49850KB)(227)       Save
Garnet granites and anatectic source rocks (pelitic gneiss) in Daqingshan and Jining-Liangcheng areas at the northern margin of the North China craton gradually transition and closely coexist in the field. The garnet granites contain many source rock enclaves, residual bodies and residual mineral phases/peritectic minerals. There are also a large number of garnet granite blocks in anatectic source rock. All these migmatites have heterogeneity macroscopically. Petrographic studies show that the mineral composition of garnet granites and the anatectic source rocks are similar and both contain garnet with similar characteristics. This can be considered a residual mineral/peritectic minerals facies type. Geochemical studies indicate that garnet granites are relatively well integrated with their anatectic source rocks, both have high Al2O3 values and TFeO/MgO ratio, with a large variation in CaO values and K2O/Na2O ratio. They are relatively enriched in light REE and large ion lithophile elements, and relatively depleted in Ta, Nb, Ti  and P. Deviating from the composition range of typical S-type granites in the world, garnet granites have lower SiO2(50.30%-73.10%) and greater MgO+TFeO(1.6%-14.8%). It is believed that this deviation from the normal S-type granite compositon is related to the introduction of residual garnet and the addition of mantle-derived materials. The garnet granites in the Daqingshan  and the Jining-Liangcheng areas were formed by two episodes of anatexis at the 2.45-2.37 Ga and 1.95-1.90 Ga respectively, consistent with the regional mantle-derived magma underplating in this area. This indicates that garnet granites are the products of large-scale partial melting of metasedimentary rocks caused by mantle-derived basic magma intruding into granulite facies metasedimentary rocks.
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Uniaxial Creep Mechanical Properties of Marble Under Hydration Freeze-Thaw Coupling
Zhao Yue, Li Lei, Yan Han, Xiao Wanshan, Su Yanjun
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1195-1203.   DOI: 10.13278/j.cnki.jjuese.20220055
Abstract106)      PDF(pc) (13174KB)(130)       Save
In order to explore the creep law of rock under the coupling action of hydration, freezing and thawing, taking the marble of an open-pit slope in Hubei as the research object, the uniaxial compression creep tests under different freeze-thaw cycles were carried out by soaking in acid, medium and alkali solutions, and the macro failure morphology and fracture micro characteristics of marble were compared and analyzed. The results showed that: 1) Under the same number of freeze-thaw cycles, the instantaneous, creep strain and creep rate in acidic environment were the largest, alkaline was the second, and neutral was the smallest. 2) The average long-term strength of marble was 0.685-0.812 of the instantaneous strength, and the long-term strength was greatly reduced. 3) The damage degree of acid solution to marble particle structure was stronger than that of alkaline solution, but with the enhancement of freeze-thaw effect, the damage degree of alkaline solution to rock structure was gradually close to that of acid solution.
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Organic Geochemical Characteristics of Lower Cambrian Black Rock Series in Ziyang, Shaanxi Province
Zhao Huibo, Feng Caixia, Liu Shen, Liu Fangxiao
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1016-1032.   DOI: 10.13278/j.cnki.jjuese.20220105
Abstract105)      PDF(pc) (25421KB)(128)       Save
The Lower Cambrian black rock series in Ziyang, Shaanxi Province is rich in organic matter and metal elements (Ba, V, Cr, Ni, Mo, Au), while there is still a lack of understanding of its organic geochemical characteristics. Based on the experimental results of polarized electron microscope, morphology under scanning electron microscope, organic carbon (TOC) and saturated hydrocarbon gas chromatography-mass spectrometry(GC-MS),the coupling relationship of organic matter and inorganic matter, organic matter source and maturity, sedimentary environment were discussed. The results show that the content of organic matter is high in the study area, and there are two kinds of occurrence modes, dispersed organic matter and aggregated organic matter. The relationship between dispersed organic matter and clay minerals is close. The average total organic carbon (TOC) content was 2.95%, affected by lithologic differences, pyrite content and types. All the samples were rich in n-alkanes, isoprenoids, steroids and terpenes. The distribution range of carbon number was from C14 to C34, which showed obvious bimodal distribution characteristics and no obvious odd-even advantage. Isoprenoid alkenes indications showed obvious phytoalkane advantage, with low value of Pr/nC17(0.36) and Ph/nC18 (0.50); The abundance of terpenoids was tricyclic terpane > pentacyclic terpane > tetracyclic terpane, a small amount of gamma wax, and the distribution of tricyclic terpane C21-C23-C24 is asymmetric inverted “V” with low average value of Tm/ Ts ratio(1.03); The distribution of regular steranes in steroids showed an asymmetric “V” distribution of C29>C27 > C28 with low average ratio of C27 rearranged steranes / C27 regular steranes(0.18) and pregnane/ C29-20r steranes(0.84). As indicated above, the origin of organic matter is mainly marine lower organisms (such as bacteria, algae, and microorganisms) and plankton, and a small amount of terrestrial lower plants are involved in the source of organic matter in some rocks (siliceous rocks); The organic matter of the whole rock has a high maturity, but it has not reached the stage of over maturity; The black rock series comes from the semi closed-closed alkaline seawater environment with anoxic reduction and low salinity.
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1078-.  
Abstract102)      PDF(pc) (23198KB)(42)       Save
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1052-.  
Abstract99)      PDF(pc) (26262KB)(62)       Save
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Groundwater Quality Characteristics in Coastal Areas and Its Potential Hazard Analysis to Groundwater Source Heat Pump System in Coastal Areas
Li Shijie, Luo Zujiang, Xu Mingzuan, Zhang Bin
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1204-1215.   DOI: 10.13278/j.cnki.jjuese.20220142
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The water chemical conditions of groundwater in coastal areas are complex. In order to find out the harm of groundwater quality to groundwater source heat pump system (GWHP), the harm mechanism was studied. Through the hydro-chemical analysis of the phreatic and First confined water in the Yancheng City, the main ion sources and causes were determined, and the harm of Mg2+, Ca2+ and Fe2+ was analyzed. Finally, the saturation index Is was calculated by PHREEQC, and the potential harm of groundwater overflow mixing and groundwater recharge superposition to the ground water source heat pump was analyzed. The results show that the TDS and hardness of groundwater in Yancheng area are high. Na+,Mg2+, Ca2+, Fe2+ HCO3- and  Cl- are the main abnormal ions. The diving ρ(TDS) is 180.42-4 497.00 mg/L, ρ (Na+),ρ (Mg2+),ρ (Ca2+) are 278.16,72.91,72.74 mg/L, respectively. The anions ρ(HCO3-) and ρ (Cl-) are 487.33 mg/L and 298.76 mg/L, respectively. The ρ (TDS) of  First confined water was 508.50-17 182.00 mg/L, ρ(Na+), ρ (Ca2+) and  ρ (Fe2+) were 1 595.06, 564.57 and 4.50 mg/L, respectively, and the ρ (Cl-) was 4 560.06 mg/L. The process of groundwater migration is influenced by various water-rock reactions such as dissolution and intrusion of ancient seawater. Major problems such as Fe(OH)3 scaling, CaCO3 and CaMg(CO3)2 precipitation and scaling will occur in the long-term operation of GWHP.
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Journal of Jilin University(Earth Science Edition)    2022, 52 (4): 1027-.  
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Evaluation of Selenium Bioavailability in the Soil-Plant System of Yinan, Shandong Province
Feng Aiping, Kang Pengyu, Liu Chuanpeng, Deng Jun, Liang Cheng, Liu Tong
Journal of Jilin University(Earth Science Edition)    2023, 53 (4): 1216-1227.   DOI: doi:10.13278/j.cnki.jjuese.20230049
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To evaluate the bioavailability of selenium in selenium-rich soil of Yinan, Shandong Province in different crops, and to speculate its source, soil, plant, and rock samples were collected accordingly from the research area, then the total   selenium content in each sample and the content  of five forms of selenium in water-soluble, weak acid extracted, reducible, oxidizable, and residual states were tested by ICP-MS, and the results were compared and analyzed. The results showed that: the total selenium content in soil is significantly constrained by spatial location and water system constraints; The effective selenium content  is positively correlated with the total selenium content, and the spatial distribution is consistent; The total selenium content in soil is positively correlated with the nitrogen and phosphorus content; The main form of selenium in soil is selenite. The fruits of three crops, peanuts, walnuts, and watermelons, grew on selenium-rich soil in the research area are enriched with selenium element. The selenium source in selenium-rich soil is related to shale, mudstone, and upstream iron ore in the regional strata, and it is speculated that the above rocks were weathered into soil and later transported to the clay and sandy clay areas by water flow, where they were adsorbed and deposited by soil clays to form selenium-rich areas.
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Source and Migration of  Selenium  in the Soil
Lei Wanshan, Lin Xin, Duan Xingxing, Liu Tuo, Yang Shengfei, Zhang Haidong, Liu Yunhua
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 264-278.   DOI: 10.13278/j.cnki.jjuese.20220084
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Natural processes and human factors can activate and migrate the selenium into and out of the soil. Finding out the provenance and migration mechanism of selenium in soil is of great scientific and practical significance for selenium-rich land management and selenium-rich industrial development. The lithosphere and dry and wet deposition of atmosphere are the most basic sources of soil selenium. Surface runoff, groundwater lixiviation, crop harvesting and volatilization of plants and microorganisms are the main ways of selenium loss. The migration of selenium in soil can be attributed to hydrodynamic migration mechanism, solid phase adsorption mechanism and absorption, degradation and volatilization mechanisms. Soil composition and physicochemical conditions affect the migration and redistribution of selenium in soil by changing the process of the above mechanism. Climate, topography and agricultural activities indirectly affect the migration and redistribution of selenium in soil by changing soil composition and physicochemical conditions. Geological background, climatic conditions, and topographic factors are very important for the distribution of selenium on a regional scale (such as continents, countries and provinces), while on a local scale (such as counties, townships and farmland), the impact of human activities, especially agricultural farming, is more significant. Based on the behavioral characteristics of selenium in soil, a series of selenium resource management strategies have been developed:1) Biofortification and remediation regulate selenium distribution and bioavailability in soil through animal and plant transformation, which is considered to be an ecologically Selenium management solution. 2) The irrigation mode adjusts the physical and chemical conditions of the soil by changing the hydrodynamic conditions, thereby changing the solid phase adsorption of the soil and the transformation of animals and plants. The water management mode combining flood irrigation and aerobic irrigation is believed to improve the availability of soil selenium. 3) Agronomic measures such as applying selenium fertilizer, phosphate fertilizer, sulfur fertilizer and liming adjust the distribution and availability of soil selenium by directly changing soil composition and physical and chemical conditions. This is a traditional selenium-rich agronomic measure, but it may also produce certain ecological effects. risk.

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The Nature of the Cenozoic Western Qaidam Basin
Wang Qianqian, Yuan Sihua, Wang Yadong, Li Weimin, Liu Yongjiang, Zheng Shigang, Zhao Yingli
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 160-181.   DOI: 10.13278/j.cnki.jjuese.20220224
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The characteristics of different stages of petroliferous basins are of great significance for the restoration of basin evolution and the evaluation of hydrocarbon generation, storage and transportation conditions. In this study, we systematically reviewed previous studies on the nature and evolution of the Cenozoic western Qaidam basin. Based on the interpretation of seismic profiles combining with the basin tectonic geometry, sedimentation rate, sedimentation phase, sedimentation cycle, sedimentation center migration and unconformity contact relationship within the basin, we concluded that the Cenozoic western Qaidam basin, as a large intracontinental depression in a compressional environment, has an asymmetric geometric configuration in the seismic section, high deposition rate but slightly lower than the western typical foreland basin, and migration of sediment centers due to strong shortening under overcompensation, with obvious reverse cycling sedimentary-tectonic development. Importantly, the deposition of Shizigou Formation is considered as the sedimentary boundary of the Cenozoic western Qaidam basin, showing that in the early stage, fine-grained far-source sediments were developed, belonging to a depression basin; While, in the later period, the sedimentation rate increased significantly, and the coarse-grained deposition developed, which had the characteristics of atypical foreland basin. The fact significantly suggests that it’s controlled by the combination of tectonic activity of the surrounding mountains and overcompensation state of the basin.
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Multidisciplinary Advancements in Geomagnetically Induced Currents Research
Yu Nian, Zhang Xuejian, Kong Wenxin, Wei Chang
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 54-67.   DOI: 10.13278/j.cnki.jjuese.20230289
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Geomagnetically induced currents (GIC) are currents induced in conductive materials on the Earth’s surface due to Earth’s magnetic field variations. GICs have the potential to cause severe damage to manufactured infrastructure, including power grids, oil and gas pipelines, and high-speed railways, resulting in adverse consequences such as power system failures, communication disruptions, and damage to electronic equipment, ultimately affecting the stability and functionality of these systems. The significance of studying GIC lies in understanding their generation mechanisms and influencing factors, thereby providing a scientific foundation for developing effective prevention and mitigation strategies. Based on an in-depth review of the progress in GIC research, this paper elaborates on the mechanisms of GIC generation and the influencing factors, encompassing the impacts of space weather, Earth’s environmental conditions, and the power system on GIC. It provides an overview of the current state of GIC research, offering integrated assessments from space physics, geophysics, and electrical engineering. Furthermore, the paper provides a detailed description of the steps involved in estimating GIC, including using geomagnetic field data and modeling, along with calculating electric fields and GIC within conductors. It emphasizes analyzing how various geophysical parameters affect GIC estimates and their interrelationships. In conclusion, the paper discusses the challenges in GIC research, highlights the potential contributions of geophysics in addressing related issues, and provides a perspective on the future of GIC research.
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Magnetic Source Variable Depth Imaging Method Based on Different Order Analytic Signals#br#
Wang Yanguo, Tian Ye, Deng Juzhi, Ge Kunpeng, Chen Xiao
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 279-291.   DOI: 10.13278/j.cnki.jjuese.20220338
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Analytic signal is a common tool for magnetic data processing and interpretation. Based on the relationship of different order analytic signals and their vertical derivative, this paper introduced a magnetic source variable depth imaging function with a depth scaled factor. The new method can be used for determining the position of filed source by using the maximum value of depth imaging, and estimating structural index on basis of the inverted depth and imaging maximum value. In addition, we can use the imaging results with different depth scaled factors and different orders to improve the reliability and usability of the new method. Model tests and applications indicate that the new method can    abtain  stronger computational  stability, higher spatial imaging resolution and more accurate field source parameter inversion results using lower-order derivatives, compared with the DEXP (depth from extreme points) methods of analytic signal ratio and local wavenumber.
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Comprehensive Lithology Recognition of Altered Igneous Reservoirs Based on Machine Learning for  Wireline and Cutting Logs in Huizhou Depression, Pearl River Mouth Basin, Northern South China Sea#br#
Guan Yao, Wang Qinghui, Feng Jin, Yang Qing, Shi Lei
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 345-358.   DOI: 10.13278/j.cnki.jjuese.20220310
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Lithology recognition plays an important role in reservoir logging evaluation, influencing the accuracy of critical parameters such as development degree and porosity. In Huizhou  26-6 well block within the Pearl River Mouth basin in the northern South China Sea, the lithology of igneous rocks is intricate, with widespread alteration significantly impacting conventional logging data. As a result, the conventional lithology identification faces difficulty in satisfying the exploration needs. To enhance the accuracy of identifying altered igneous rocks, we integrate conventional logging and element cutting logging to establish lithology identification methods through diverse machine learning algorithms. A comparative analysis leads to a comprehensive identification method of discerning altered igneous rocks. Initially, a core element data-based correction method for element cutting logging is established to obtain reliable data. Subsequently, the k-nearest neighbor (KNN) method and the support vector machine (SVM) method are employed to identify the lithology of six igneous rocks in the study area—diorite, tectonic schist, altered diabase, granodiorite, altered granite, and granite.  In the target layer of four wells with rock slice identification data in Huizhou 26-6 well block, data points (145 in total) are extracted according to the corresponding depth, of which 80% are used as training samples and the remaining 20% as test samples. Taking  sample test accuracy and  whole well lithology recognition effect as  evaluation indicators, the results of comparing the two algorithms indicate that the recognition accuracy of KNN and SVM algorithms is both 92.65%, but the whole well recognition effect of KNN algorithm is more in line with the distribution characteristics of stratigraphic lithology, indicating that the comprehensive lithology recognition based on KNN algorithm is more suitable for the study area.
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Influence of Different Power Supply Direction Excitation on Three-Dimensional Induced Polarization Exploration Effect with  #br# Central Gradient Array of Multi-Group Power Supply Pole Distance Combination#br#
Gu Guanwen, Wang Shunji, Li Tonglin, Wu Ye, Xu Zhihe
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 292-309.   DOI: 10.13278/j.cnki.jjuese.20220345
Abstract34)      PDF(pc) (20242KB)(57)       Save
This study investigates the impact of different power supply direction excitation on the exploration effect of the three-dimensional (3D) induced polarization (IP) method, for a central gradient array of  multi-group power supply pole distance combinations. We employ the 3D unstructured finite element numerical simulation for direct current  point power supply and the incomplete Gauss-Newton 3D inversion. The goal is to provide a basis for the rational selection of power supply directions for 3D IP measurements. First, we design various 3D geoelectric models and conduct forward and inverse modeling for three power supply modes: transverse, longitudinal, and transverse/longitudinal bidirectional combinations. Then we perform 3D inversion on IP measured data obtained in a mining area under these three power supply modes. Finally, the 3D inversion results of theoretical model synthesis data and measured data and the existing geological data of the mining area are synthetically analyzed. We find that 3D inversion results for IP data under transverse, longitudinal, and transverse/longitudinal bidirectional combination power supply modes can effectively depict the lithological and structural distribution characteristics. In terms of revealing local anomaly information, the bidirectional combined power supply IP data yields the most abundant and complete information. By contrast, the inversion results of single-directional power supply IP data may lack some effective anomaly information, presenting incomplete anomaly details.
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Mechanism of Ion Erosion on Concrete Under  Action of Dry-Wet Cycles
Wang Boxin, Huang Zhixin, Bi Guangze
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 558-569.   DOI: 10.13278/j.cnki.jjuese.20220334
Abstract33)      PDF(pc) (22908KB)(7)       Save

In order to address the significant degradation of concrete durability caused by long-term external sulfate and carbonate corrosion under dry-wet cycle conditions. This article investigates the erosion and migration patterns of sulfate and carbonate ions inside concrete under dry-wet cycling conditions. Firstly, the damage mechanism of the two ions on concrete erosion was analyzed and compared through the chemical reaction process of ion erosion on concrete and scanning electron microscope (SEM) experiments. Then, the transmission and exchange laws of sulfate ions and carbonate ions at the interface between the concrete surface and the outside world were analyzed by referencing the room model.  The results indicate that, 1) Within 180 days, ion erosion mainly occurs within the range of 0-20 mm on the concrete surface, and the predicted value of the room model deviates from the actual value by about 0.75. 2) The depth of concrete erosion is positively correlated with the water cement ratio, and the room model can predict the degree of concrete erosion. 3) The failure of concrete can be explained from the perspective of the expansion pressure caused by the chemical reaction products of sulfates and carbonates.

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Theoretical Framework of L-S Thermoacoustoelasticity Based on Rational Extended Thermodynamics

Li Yuanxie, Liu Cai
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 655-687.   DOI: 10.13278/j.cnki.jjuese.20230002
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This paper combines L-S thermoelasticity with acoustoelasticity based on  continuum mechanics and analysis process of rational extended thermodynamics to establish the basic framework of L-S thermoacoustoelasticity, including four components: kinematics, mechanics and thermodynamics, constitutive equations and evolution equations, and fundamental field equations. In the kinematic part, Lagrangian description and Eulerian description are distinguished, as well as three different states and configurations, while two types of transition processes from the natural state to the initial state are defined for the case of thermoacoustoelasticity; In the mechanics and thermodynamics part, the laws of conservation of mass, conservation of momentum, conservation of angular momentum, conservation of energy, and the entropy production inequality are given, which lead to the limitations of classical irreversible thermodynamics; In the part of the constitutive equations and evolution equations, the principle of extended irreversible thermodynamics is introduced, and the constitutive equations and evolution equations of thermoacoustoelasticity from the natural state to the initial state and those from the initial state to the final state are derived based on the process of rational extended thermodynamics, taking heat flux as the constitutive independent variable and considering the correlation of heat flux with strain and temperature; In the last part, the equations of motion and the first-order velocity-stress- heat flux-temperature differential equations for numerical simulations are given.
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Study on Water Restoration in the Dried-up River of the Fuyang River Basin Based on the SWAT Model#br#
Hong Mei, Zhao Mingming, Wei Tao, Lin Haodong
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 253-263.   DOI: 10.13278/j.cnki.jjuese.20220051
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In order to achieve the goal of restoring water to the river as long as possible and to restore the basic ecological functions, a SWAT (soil and water assessment tool) hydrological model for the Fuyang River basin was established based on the current status of water conservation measures and water transfer projects. The different ecological water replenishment scenarios were designed, the variation of runoff volume and the restoration of the annual number of days with water were analyzed for different scenarios. Ecological restoration effects were analyzed based on the ecological base flow standard. The results show that the river ecological restoration effect is better in the water conservation scenario and the water transfer scenario in the Handan section of Fuyang River basin, and 184 days of water restoration from May to October can be achieved through the upstream water conservation measures and the scenario of 1.00×108 m3/a of supplemental annual water transfer, and the restored runoff volume of 3 486.7×104 m3/a, the water replenishment can reach the ecological baseflow standard and guarantee the basic ecological function of the river. The Xingtai section in the lower reaches of Fuyang River has less restored runoff under water-saving and water transfer scenarios, so the number of days with water in the river does not meet the standard, and it needs to supplement the external water transfer volume of 1.50×108 m3/a under the upstream water conservation condition to achieve the restoration of the annual number of days with water is 304 days and the restored runoff volume of 1 906.5×104 m3/a, and Xingtai section under the scenario of achieving the target of restoring water. The ecological replenishment scheme of increasing water transfer for single point replenishment in different periods needs to be considered as it cannot reach the ecological base flow standard of the river.
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Fractal Structure and Application Prospect of Xingguo-Ningdu Fluorite Metallogenic Belt in Southern Jiangxi, China#br#
Cui Zhongliang, Zhou Jiaxi, , Luo Kai,
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 108-124.   DOI: 10.13278/j.cnki.jjuese.20220186
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As one of the important non-metallic strategic mineral resources, the metallogenic regularity, ore prospecting and exploration of fluorite are widely investigated byeconomic geologists. The Xingguo-Ningdu metallogenic belt in southern Jiangxi Province, located at the intersection of the NE-trending Wuyishan metallogenic belt and EW-trending Nanling metallogenic belt, develops a series of fluorite deposits. Previous studies have primarily attributed the deposits to fault control, but the quantitative characterization of the coupling relationship between fractures and the spatial distribution of the fluorite deposits is seldom reported. Based on fractal theory, this paper aims to describe the fractal textural characteristics between fractures and fluorite deposits in Xingguo-Ningdu metallogenic belt to identify key ore-forming and prospecting areas of fluorite. The results show that: 1) The NE-NNE-trending fracture capacity dimension, information dimension and correlation dimension of the study area are 1.609 0, 1.608 9, and 1.594 7, respectively, indicating superior metallogenic geological conditions and a strong relationship between NE-NNE faults and fluorite mineralization in the study area; 2) The capacity dimension, information dimension and correlation dimension of fluorite deposits are 0.937 9, 0.921 5 and 0.926  2, respectively. When there is a statistical center deposit, the fractal dimension of the number fractal distribution of fluorite deposits is 0.784 1, and the fractal dimension of the density fractal distribution is 0.784. When there is no statistical center deposit, the fractal dimension of the number fractal distribution of fluorite deposits is 1.129 6, and the fractal dimension of the density fractal distribution is 1.130; 3) According to the coupling characteristics of the fractal dimension value of fracture and the spatial distribution of fluorite deposits in the study area, as well as the fractal characteristics of the number and density of fluorite deposits, the three-level favorable metallogenic areas are comprehensively delineated, in which the I-level favorable metallogenic area is the area with the best metallogenic condition and the largest metallogenic potential; 4) According to the coupling characteristics of fracture dimension value and spatial distribution of deposits, the number and density fractal characteristics of deposits, the key ore forming and prospecting areas in the fluorite ore concentration area or metallogenic belt controlled by fracture system can be quickly and effectively delineated, which is expected to provide important reference information for the resource exploration of fluorite.
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Multiple Suppression Method of Parabolic Radon Transform Based on L1/2   Regularization#br#
Wu Qiuying, Hu Bin, Liu Cai, Gao Rui
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 323-336.   DOI: 10.13278/j.cnki.jjuese.20220307
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In the context of seismic data processing, the presence of multiples poses inherent challenges to the imaging and interpretation of seismic data. The effective suppression of these multiples stands as a key issue in seismic exploration. Leveraging its high efficiency, the parabolic Radon transform emerges as a widely used technique for multiple suppression. However, in field seismic data acqisition, due to the limited offset, energy diffusion and illusions reduce the effect of multiple suppression in the Radon domain. In response to this challenge, we propose a L1/2-regularized high-resolution parabolic Radon transform with sparse inversion, where the inverse problem is solved by  generalized iterated shrinkage algorithm (GISA). The L1/2 regularization chosen for its robust sparse constraint capabilities plays an important role in enhancing the solution sparsity and improving the signal-noise separation. Compared with the least square inversion and the sparse inversion method based on L1 regularization, the L1/2-regularized sparse inversion of using the high-resolution parabolic Radon transform can suppress multiples effectively and ensure the consistency between the reconstructed data and the original data.
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The Discovery and Geological Implications of Late Neoarchean Kaligranites in Benxi Area, Liaoning Province#br#
Yin Zhigang, Li Mengmeng, Wu Zijie, Chen Jundian, Jiang Ran, Zhang Kaiqiang, Jiang Qi, Guo Hao
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 125-139.   DOI: 10.13278/j.cnki.jjuese.20220150
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The Benxi area of Liaoning Province is located in the northeastern part of the eastern North China craton, where Neoarchean plutonic intrusive rocks and metamorphic supracrustal rocks are widely developed, but no kaligranites have been reported. The formation process of kaligranites is an important symbol of the maturation and stability of the early continental crust. The discovery of kaligranites is significant for the systematic study of the formation and evolution of the early continental crust in the North China craton. In this paper, the petrology, diagenetic age, and petrogeochemistry of kaligranites in Majiagou, Benxi area are studied, and the petrogenesis and tectonic setting of formation are discussed. Majiagou pluton is a gneissic medium-fine-grained biotite monzogranite. The  zircon U-Pb dating data show that the 207 Pb/ 206 Pb weighted average age is (2 490±21) Ma, suggesting the kaligranites formed in the Late Neoarchean. The granite is weakly peraluminous and high potassium calc alkaline kaligranite. The high field strength elements La, Zr, Th and large ion lithophile elements K, Nd are enriched, while high field elements P, strength elements Nb and large ion lithophile elements Sr, Ti are depleted. The REE partition curve is rightward with negative Eu anomalies, indicating S-type granite. The magma originated from the crust and the product of partial melting of metamorphic mudstone, which formed in an extensional environment after collisional orogenesis at active continental margins. It represents the last magmatic activity before the formation of the consolidated basement of the Archean craton in North China, and marks the completion of the collage of micro-blocks in Benxi area in the Late Neoarchean, and together with other regions, forming a stable North China Archean craton.
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Resonance Data Based on Differential Structure
Zhang Yang, Wang Meiting, Shang Xinlei
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 46-53.   DOI: 10.13278/j.cnki.jjuese.20230288
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Surface nuclear magnetic resonance (SNMR) emerges as a non-invasive geophysical method with widespread applications in the qualitative and quantitative detection of groundwater. Its utility extends to resource exploration, geological disaster warning, and environmental monitoring. However, the practical implementation of this method encounters challenges as weak SNMR signals often contend with the pervasive noise in complex environments, hampering effective signal acquisition. In response to this issue, we propose a novel SNMR data noise suppression technique based on a differential structure. This method involves the strategic placement of two receiving coils equidistantly above and below the transmitting coil. This configuration can cancel out a significant portion of ambient noise and mitigates the effects of transceiver coil coupling in real time. Numerical experiments verify that the new method can achieve noise suppression and the reliable acquisition of free induction decay (FID) signals.

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Application of In-Situ Stress Measurement Technology of  Ultra Deep Survey Borehole ASR Method#br#
Zhang Xiaolin, Ying Li, Zhao Dong’an
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 198-207.   DOI: 10.13278/j.cnki.jjuese.20220118
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Baolingshan tunnel is a key and difficult control engineering in the first section of a certain railway. The depth of survey Borehole DZ-06 is 2 118.00 m, which is the deepest survey borehole in this railway. Appropriate cores were selected at the depths of 2 072.53 m and 2 084.27 m, and in-situ stress test was carried out by anelastic strain recovery method(ASR). The results show that in the depth range of 2 072.53-2 084.27 m, the average values of the maximum principal stress, intermediate principal stress and minimum principal stress obtained from the two measuring points of ASR method are 59.70, 54.03 and 30.74 MPa respectively. The maximum principal stress is nearly horizontal and the direction is close to SN direction, indicating that the area is dominated by horizontal tectonic stress. The average value of the maximum principal stress test result of ASR method is in good agreement with the regression value from the hydraulic fracturing method test, the consistency of the minimum principal stress test value and the regression value of the hydraulic fracturing method test result is in a reasonable range, and the horizontal principal stress direction test results from the two methods are basically consistent.
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Lithology Identification Method for Logging While Drilling Based on Random Tree Embedding
Wang Xinling, Zhu Xinyi, Zhang Hongbing, Sun Bo, Xu Kexin
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 701-708.   DOI: 10.13278/j.cnki. jjuese.20230193
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Lithology identification is an important task in reservoir evaluation. With the development of machine learning methods, intelligent lithology identification has become a popular research direction. Logging while drilling (LWD) technology has been widely used. However, in the actual production process, due to the high-temperature and high-pressure operating conditions, only a few logging parameters can be measured by LWD. Due to the small number of logging parameters,  machine learning model is not able to fully tap into the few parameters. To solve this problem, this paper introduced random tree embedding into LWD lithology identification. The low dimensional LWD data was encoded by the binary tree and transformed into high dimentional sparse features, and  the upgraded data was used for training to improve the discriminative ability of the machine learning model. The comparative experiment results in this paper show that the random forest method with random tree embedding has the best recognition effect, the accuracy and F1 value are improved by 3.16% and 3.25% respectively, compared with the direct use of random forest, and outperforms the gradient boosted tree, extremely random tree and particle swarm optimization support vector machine algorithms.

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Destabilization Mechanism of Ziquejie Terrace

Ouyang Qi, Chen Xin, Wei Runchu, Wu Shimeng, Zhu Zhiyuan
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 581-591.   DOI: 10.13278/j.cnki.jjuese.20220268
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In order to discuss the influence of rainfall infiltration on the stability of granite terrace slope, this paper takes the Ziquejie terrace in Hunan Province as an example. Based on the analysis of the geological conditions of Ziquejie terrace, the seepage field and stability of different slope gradients and different  soil layer thicknesses under rainstorm conditions were analyzed based on the coupling of multiple modules of the finite element numerical simulation software Geostudio. The results show that under the working condition of 90 mm/d rainfall intensity and 5 days  rainfall duration, the slopes with 35° and 40° gradients are in a state of destabilization, and the stability coefficient is negatively correlated with the increase of slope gradient; The thicker the fully weathered soil layer is, the lower the safety factor of the slope is. After 5 days of rainfall, the stability coefficients of different soil layers under different working conditions are similar. However, when there is no rainfall, the thinner the fully weathered soil layer is, the more stable the slope is.


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Three Roaming Algorithms of Chongqing City Based on Cesium and Their Comparative Analyses
Li Ying, Zhao Ningxi
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 709-720.   DOI: 10.13278/j.cnki.jjuese.20230029
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The roaming function is widely used in the fields of digital earth, virtual reality and simulation. Previous researches mostly focused on desktop applications under client/server(C/S) structure. This paper constructs a virtual Earth based on Cesium, an open-source 3D geography framework on the Web side under browser/server(B/S) structure and designs three different roaming algorithms: conventional algorithm, callback function algorithm and Lagrange interpolation algorithm. Then, the tilting photography model of downtown Chongqing was successfully loaded on the virtual Earth’s surface to realize the roaming functions of the three different algorithms. Finally, the effectiveness of the three algorithms was compared in terms of frames per second (FPS) and network latency (NL). The results show that the average FPS in the first 50 s for conventional algorithm, callback function algorithm and Lagrange interpolation algorithm are 70, 74 and 80 Hz, respectively; The average NL in the first 50 s for conventional algorithm, callback function algorithm and Lagrange interpolation algorithm are 14.145, 13.166 and 12.419 ms, respectively. In terms of FPS, callback function algorithm is 5.714% higher than conventional algorithm, while Lagrange interpolation algorithm is 14.286% higher than conventional algorithm. In terms of NL, callback function algorithm is 6.921% shorter than conventional algorithm, while Lagrange interpolation algorithm is 12.202% shorter than conventional algorithm. Overall, the final order of the three algorithms’ running efficiency from largest to smallest is: Lagrange interpolation algorithm, callback function algorithm, and conventional algorithm. Namely, callback function algorithm and Lagrange interpolation algorithm have certain improvements compared with conventional algorithm in the process of roaming, and Lagrange interpolation algorithm can achieve the most efficient and smooth operation and rendering effects.

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Evaluation of Eco-Geological Environment Quality in Strait Coastal Areas Based on AHP:Taking Southwest Coastal Areas of Malaysia

of North Coast of Malacca Strait as an Example

Wu Dongzhe, Jiang Qigang, Gu Zongrui, Zhang Sen, Fu Changliang
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 619-632.   DOI: 10.13278/j.cnki.jjuese.20220170
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The eco-geological environment quality shows the overall situation of regional geological action and ecological spatial distribution. In order to provide the basis for the ecological protection and restoration of the southwest coastal areas of Malaysia of the north coast   of Malacca Strait and the investment and construction of “One Belt and One Road”, GIS technology and hierarchical analysis method are combined. Based on the data set of Malaysia basic geology and geological disaster remote sensing geological application and mapping project results, the eco-geological environment quality evaluation index system of the southwest coastal area of Malaysia along the north coast of  Malacca Strait was constructed and comprehensively evaluated. Through the analysis of the results, the eco-geological environment quality of the study area was divided into four grades: excellent, good, medium and poor. The area of excellent and good area was larger, which was 2 753.31 km2 and 2 960.33 km2, respectively, accounting for 34.19% and 36.76% of the total area of the study area, and mainly distributed in the hilly areas of the northern coastal plain. The medium and poor districts are 1 702.72 km2 and 618.57 km2, accounting for 21.37% and 7.68% of the total area of the research area, respectively, and are mainly distributed in southern Sembilan central , Selangor and northern Malacca. According to the evaluation results, the eco-geological environment quality of this area is good on the whole. The  excellent area and good area account for 70.00% of the total area of the study area. The medium  area and poor area are mainly restricted by the stratigraphic structure and ecological conditions, so it is necessary to carry out environmental protection and ecological restoration according to specific problems.

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Genesis of Neoproterozoic Granite Gneiss in Xinyi Area of Sulu Orogenic Belt and Its Response to the Breakup of Rodinia Supercontinent#br#
Zhang Qi, Zhou Qizhong, Sun Chao, Shi Jianbin, Wang Bo, Hou Qi, Luo Yue, Feng Xuezhi, Wang Guoqiang
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 140-159.   DOI: 10.13278/j.cnki.jjuese.20220115
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The granite gneiss in the Xinyi area is located on the western margin of the Sulu orogenic belt. This paper discusses its petrogenesis and tectonic environment by examining petrography, rock geochemistry, and zircon U-Pb isotopic chronology of the granite gneiss. It also reveals the repercussions of the breakup event of the Rodinia supercontinent in this area. The findings indicate that the granite gneiss in the study area belongs to the meta-aluminous-weak peraluminous A-type granite, characterized by high SiO2 content, rich alkali, low CaO and Al2O3 contents, and a right-dipping seagull-type rare earth distribution pattern. It is enriched in Rb, Zr, Hf elements, while being severely depleted in Sr, Eu, Nb, Ta elements. The age of the granite gneiss is 746.0-742.5 Ma. The granite gneiss in the Xinyi area originated from the partial melting of lower crustal material and a small amount of mantle-derived material. In the process of magma evolution, it underwent the separation and crystallization of potassium feldspar and plagioclase, and eventually formed through ultra-high pressure metamorphism. The granite gneiss in the Xinyi area was formed in a post-collisional extensional environment in the Neoproterozoic, marking the initial response to the Rodinia supercontinent breakup event in study area of the Sulu orogenic belt.
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Application of Tilt-Euler Method Based on Regularization  in Edge Depth Inversion
Luo Xingang, Wang Wanyin,
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 633-646.   DOI: 10.13278/j.cnki.jjuese.20230035
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The edge depth of geological bodies plays a critical role in the semi-quantitative interpretation of gravity and magnetic field data. Since gravity and magnetic anomalies and their derivatives of all orders satisfy the Euler homogeneous equation, the tilt-Euler method is favored for inversion of edge depth. However, it is found that when the total horizontal derivative or the total gradient mode of gravity or magnetic anomalies is equal to zero, the first-order derivative of the tilt angle cannot be calculated, resulting in the tilt angle cannot satisfy the Euler equation, and the tilt-Euler method cannot be used. In order to solve this problem, based on the regularization idea, we modified the first-order derivative of the tilt angle, so that the first-order derivative of the tilt angle can still be calculated when the total horizontal derivative or the total gradient mode of gravity or magnetic anomalies is equal to zero, and the modified derivatives of the tilt angle still satisfy the Euler equation. We call the improved method the rtilt-Euler method. At the same time, the normalized vertical derivative of the total horizontal derivative (NVDR-THDR) with higher edge recognition accuracy was used to constrain the inversion results and eliminate the bad points deviating from the edge position. The results of the model test show that the improved method eliminates the problems that the tilt angle derivative cannot be calculated and the instability of the inversion restults when the total horizontal derivative or the total gradient mode of gravity or magnetic anomalies is zero or very small.   This method was applied to the edge depth inversion of iron oxide, copper-gold (IOCG) deposit of the Olympic Dam in Australia. The results show that the edge depth of the iron oxide, copper-gold deposit is mainly concentrated in the depth ranges of 0-100 m and 100-200   m, which is consistent with the edge depth of 0-200 m shown by the sedimentary profile, proving the effectiveness of the method.

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Deep Metallogenic Prediction Based on 3D Geological-Geophysical Model:A Case Study of  Yongxin Gold Deposit in Heihe Area

Zhao Zhonghai, Cui Xiaomeng, Sun Jinggui, Chen Jun, Qiao Kai, Liang Shanshan, Manirambona Alain Jospin
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 498-515.   DOI: 10.13278/j.cnki.jjuese.20210124
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Heilongjiang Yongxin gold deposit is located at the intersection of the Xing’an and Songnen blocks in the eastern section of the Xingmeng orogenic belt. It is a large-scale gold deposit newly discovered. In order to in-depth explore the metallogenic potential of the periphery and depth of the Yongxin gold deposit, based on the analysis of typical deposits, audio-frequency magnetotelluric sounding and combined gravity and magnetic profiles, the three-dimensional geological modeling software Creatar XModeling was used to construct three geological model models of the region and the deposit. The three-dimensional morphology of the main ore-controlling geological bodies was depicted, and the deep structural geological characteristics of the area, the spatial distribution characteristics of the ore bodies, and the relationship with geological elements were revealed. Then, using the cube prediction model prospecting method, according to the weight of evidence method, multi-source information such as geology and geophysics of the study area was fused, eight deep prospecting prediction targets were delineated. The drilling verification of some of these deep targets area obtained multiple mineralization information, which verified the accuracy and reliability of this deep prediction, indicating significant metallogenic potential in the deep part of the study area.


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Distribution Characteristics and Influencing Factors of Aboveground Biomass in Typical Grassland Ecosystem in Xilin River Basin

Liu Tingxi, Zhao Xinyu, Duan Limin, Wang Yixuan, Li Mingyang, Li Yuankang
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 604-618.   DOI: 10.13278/j.cnki.jjuese.20220145
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In order to systematically quantify the synergistic relationship between environmental factors and their regulation of spatial and temporal patterns of biomass, taking the Xilin River basin as the study area, this study measured the aboveground biomass (AGB), soil water content, soil density, organic carbon mass fraction, total nitrogen mass fraction, soil pH and other environmental factors of the typical grassland ecosystem from May to September 2020. The relationship between AGB and driving factors were analyzed by using the geographic detector method. The results show that: 1) Watershed-level AGB increases stably at the beginning stage of the growing season, displays the highest increase rate in July, and reaches the maximum on September 3rd. AGB in the upstream and downstream is 209.12 and 147.19 g/m2, respectively. AGB in the upstream of the watershed is significantly higher than that in the downstream (significance level p<0.05), and the overall spatial pattern of AGB shows a decreasing trend from the southeast to the northwest in the watershed. 2) During the entire vegetation growing season, meteorological factors (precipitation and air temperature) are key factors driving the changes in AGB, with an explanation rate of more than 60.0% in the regression model. At the end of the growing season, in addition to meteorological factors, soil pH also significantly influences the dynamics of AGB in time and space. 3) At each stage of the growing season, the interaction between environmental factors shows nonlinear enhancement and double-factor enhancement. At the beginning of the growing season, the interaction between precipitation and  dry density of soil shows the most influential. When soil water content reaches a relatively high level, the interaction of soil dry density with other environmental factors (precipitation, air temperature, pH) exerts a significant impact on the AGB in the peak and late stages of the growing season vegetation growth in the basin.

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Elemental Composition and Metallogenic Significance of  Ore Minerals in  Na’e Granite-Pegmatite Type Beryllium Deposit in Western Yunnan Province

Ming Tianxue, Tang Zhong, Li Rong, He Xiaohu, Tian Sumei, Yin Wei, Qin Yongkai, Bao Congfa, Li Liang, Yang Siqi, Zhang Zijun
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 479-497.   DOI: 10.13278/j.cnki.jjuese.20230126
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Na’e small pegmatitic beryllium deposit has recently been proved in the western Yunnan Province. The ore bodies are found in garnet and albitite granite pegmatite dikes within monzonitic granite. These ore bodies range from 100-1 150 m in length, 0.43-3.70 m in thickness ,and contain BeO, Ta2O5, Rb2O in concentrations of 0.007%-1.790%, 0.003 2%-0.053 3% and 0.041%-0.317%, respectively. The mainly major useful element in the ore is beryllium, associated with tantalum and rubidium. Some few ore mainly contains tantalum, and associated with beryllium and rubidium. The ore minerals include beryl, niobium tantalite, muscovite and K-feldspar. The beryl-bearing pegmatite is a siginificant prospecting indicator in the area, followed by garnet bearing albionite pegmatite. EPMA results show that beryl falls into the alkali-free beryl to low alkali beryl. The molecular formula for beryl is Be2.8928-2.9481Al1.9766-2.0225Si6O18. Muscovite contains w(Li2O) 0.500 1%-2.427 9% and w(Rb2O) 0.730 3%-2.304 2%, belonging to muscovite-polysilica muscovite-Li-rich muscovite. K-feldspar has a high w(Rb2O) content of 0.486 1%-1.033 4%, with a molecular formula of K0.8932-0.9713 \[Al1.0013-1.0151 Si2.9809-2.9990O8\]. Energy spectrum of garnet is characterized by the development of Mn and Fe bipeaks, mainly spessartine (Spe) and almandine (Alm), with spessartine accounting for 67.02%-69.07%, indicating a magmatic origin of spessartine. Beryllium is mainly occurred in beryl, rubidium in K-feldspar and muscovite, and lithium in muscovite-polysilica muscovite-Li-rich muscovite. The composition of muscovite and berylite shows that lithium was not initially enriched in granitic magmas in the Na’e  area, but the late pegmatite evolution involving highly enriched F-Li fluid activity in magmas played an important factor in the abnormal enrichment of rare metals in this area.

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Response to the Magmatic Process of Mantle Plume with Basalt in the Shawan Area#br#
Cheng Lian, Xi Aihua, Hu Youshan, Ge Yuhui, Ren Jie, Zheng Jiang, Jiang Huan
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 182-197.   DOI: 10.13278/j.cnki.jjuese.20220048
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A large area of Permian basalt is exposed near Shawan District, Leshan City, which is an important part of Emeishan large igneous province. Petrological and geochemical analysis show that the basalts are mainly dense massive pyroxene basalts, oblique porphyry basalts and trachyte basalts. The major elements indicate  that basalts belong to high-titanium tholeiite series. The normalized rare earth element pattern of chondrites for basalts in the Shawan area exhibits right-dipping patterns with LREE enrichment and a high degree of fractionation of light and heavy rare earth elements. The normalized trace element distribution map of the primordial mantle shows that they are enriched in large ion lithophile elements (LILE) such as Th、 U etc, but depleted in trace elements related to fluids (Sr and P) with negative Eu anomalies. It is similar to the ocean island basalts (OIB) and high-titanium basalts that erupted in the late period near Binchuan, Yunnan, suggesting that the basalts around Emeishan were formed in an intraplate rift environment induced by a mantle plume. The magma originated from the low-degree partial melting of the garnet peridotite and the separation and crystallization of plagioclase, and weak crustal contamination occurred during the ascent. The geochemical comparison between the basalts in the intermediate zone and the basalts in the inner zone of the large igneous province reveals that the basalts in Shawan area are the product of late magmatism in the large igneous province, and the main body is characterized by the edge of the mantle plume itself.
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Cluster Analysis of Influencing Factors of Surface Subsidence in Shield Interval of Sandy Gravel Stratum#br#
Wang Wei, Wang Xing, Zhou Xun, Wei Shengda
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 219-230.   DOI: 10.13278/j.cnki.jjuese.20220088
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In order to grasp the comprehensive influence law of shield tunneling parameters and geological conditions on surface subsidence between shield intervals in sandy gravel stratum, a shield interval of Chengdu Metro is chosen as a case study, combined with the relationship between the surface subsidence and tunneling parameters of the our study team in the early stage, the total thrust,cutter head speed,screw machine speed,overlying soil thickness,groundwater level and gravel stratum thickness are determined as clustering indexes. The K-means algorithm is applied to cluster the actual monitoring data of each parameter index, and the influence of each index on the surface subsidence is analyzed comprehensively. The research results show that: 1) According to the results of K-means clustering, the monitoring points, corresponding to construction sections, are divided into three risk levels of surface subsidence, 1-3 is strong dangerous (Grade Ⅰ), 7-13, 16-19, 25-34 are weak dangerous (Grade Ⅱ), 4-6, 14-15, 20-24 are safe (Grade Ⅲ). 2) According to the clustering results, there is a positive and negative correlation between tunneling parameters, stratum structure and surface subsidence in a specific range. 3) Through an analysis of the relationship between geological structure, tunneling parameters and surface settlement, it is determined that when the overlying soil layer is thick, the groundwater level is low, and the gravel layer is thick, the control range of excavation parameters is a total thrust of 29 034.00-31 181.95 kN, cutterhead rotation speed of 1.25-1.32 r/min, and screw conveyor rotation speed of 6.13-6.98 r/min. When the overlying soil layer is thin, the groundwater level is low, and the gravel layer is thin, the control range of excavation parameters is a total thrust of 34 419.89-36 867.28 kN, cutterhead rotation speed of 1.44-1.45 r/min, and screw conveyor rotation speed of 5.74-6.99 r/min.
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Creep Damage Constitutive Model of Marble Under Hydration Freeze-Thaw Coupling#br#
Zhao Yue, Si Yunhang, Zhang Yidan, Zhao Jingyu
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 231-241.   DOI: 10.13278/j.cnki.jjuese.20230153
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To describe the creep characteristics of rocks under hydration freeze-thaw coupling conditions, uniaxial compression creep and nuclear magnetic resonance tests were conducted on marble under acidic, alkaline, neutral solutions and different freeze-thaw cycle conditions. T2 spectrum distribution and creep test results were analyzed, and coupled damage evolution was carried out. Finally, a new creep damage constitutive model considering the coupling of hydration freeze-thaw and stress was obtained. The results show that: 1) The T2 spectrum of marble exhibits three peaks, and pore in the rock is mainly composed of large size pores. 2) The freeze-thaw cycle promotes the development of pores in marble, and the influence degree of different solution environments on pore development from high to lower is acidic, alkaline, and neutral. 3) The hydration freeze-thaw and load damage variables were constructed to establish a new creep damage constitutive model of marble under the coupling conditions of hydration freeze-thaw. 4) The average R2 of 50 freeze-thaw cycles of three different solutions of marble simulated by a new model is 0.985 4, while the average R2 of the basic model is only 0.919 4.
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Attribution of Neoproterozoic Meta-Volcanic Series  in Gengji-Banqiao Area, Northern Hubei Province:Evidence from Zircon U-Pb Dating and Hf Isotopes

Yuan Dongyang, Shi Wei, Liu Demin, Huang Tiantong, Xu Longsheng, Chen Chao, , Kong Lingyao
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 516-530.   DOI: 10.13278/j.cnki.jjuese.20220199
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There are two sets of meta-volcanic series scattered among the Sinian-Ordovician in  Gengji and Banqiao area of Zaoyang City, northern Hubei Province, Northern Yangtze craton. Their attribution is disputed by the Wudang Group and Huashan Group, and has lacked in-depth research for a long time. Through systematic field investigation, LA-ICP-MS zircon U-Pb dating and Lu-Hf isotopic analysis, we propose that the meta-volcanic series in the Gengji area were mainly light gray and grayish white metamorphic acidic pebbly pyroclastic tuff, crystalline tuff, vitroclastic tuff and siltstone, associated with the siliceous striated stromatolite dolomite of the Dagushi Group. The zircon age for the metamorphic pyroclastic tuff from Gengji is 821.7 Ma with zircon εHf(t) values of -2.44-9.70, indicating that they may be part of the Huashan Group in the Northern Yangtze craton. However, the meta-volcanic series in the Banqiao area were mainly composed of grainy and white metamorphic acid clastic rock tuff, volcanic tuff, acid volcanic rock and siltstone, and associated with a large number of basic intrusive rocks. The zircon age of the metamorphic acid volcanic rocks from Banqiao is 741.2 Ma with zircon εHf(t) values of 4.62-9.56, indicating they belong to the Wudang Group in the South Qinling orogen, and may be a remnant of the thrust nappe during Indosinian.


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Transient Electromagnetic Weighted Laterally-Constrained Inversion of Inclined Strata in Coal Mine#br#
Gao Xiaowei, Su Chao, Pang Shaodong
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 310-322.   DOI: 10.13278/j.cnki.jjuese.20230025
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The traditional single-set one-dimensional(1D) inversion is the most widely used technique for the processing and interpretation of transient electromagnetic data in coal mines. However, this approach becomes inadequate when the stratum exhibits a significant dip, as the single-set horizontal layered model fails to accurately represent the electrical distribution characteristics. To address this limitation, we employ the weighted laterally-constrained inversion method to constrain the layer interface depth and incorporate the difference in geoelectric parameters between adjacent measurement points into the objective function as a constraint term. We describe the transient electromagnetic 1D forward and inversion theory, and detail the inversion method with weighted lateral constraints. The influence of the weighting factor on inversion results is analyzed using the H-type and K-type models with varying inclinations. Compared with  the traditional 1D inversion, the weighted laterally-constrained inversion is a pseudo-2D inversion method by establishing   layer parameters and  depth-weighted constraint equations  and synthesizing total inversion equations. The obtained resistivity profiles exhibit strong agreement with actual models and demonstrate good longitudinal and transverse continuity. The employed method effectively restores the electrical distribution of inclined strata, and the inversion results match the actual geological data.
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One-Dimensional Secondary Consolidation Creep Constitutive Model of Soft Mudstone Based on Fractional Order Theory#br#
Ren Siyuan, Ni Wankui, Chen Junting, Tuo Wenxin, Yang Zhenzhen
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 242-252.   DOI: 10.13278/j.cnki.jjuese.20220119
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Disasters induced by rock creep in engineering are common, and soft rock creep is also more common in actual engineering. In order to explore the soft rock creep characteristics and accurately predict the soft rock creep deformation. In this study, firstly, a one-dimensional secondary consolidation creep test was carried out on the soft mudstone in Lund area of Guyuan City, Ningxia, and the creep characteristics of soft mudstone under the one-dimensional secondary consolidation creep test were analyzed. Secondly, the concept of fractional order theory was introduced to derive the fractional order Burgers model constitutive equation which can describe the nonlinear creep characteristics. Finally, the lsqcurvefit algorithm in Matlab was used to numerically solve the one-dimensional secondary consolidation creep test data of soft mudstone, and the effect of fractional order number on the one-dimensional secondary consolidation creep curve of soft mudstone was analyzed. One-dimensional secondary consolidation creep test shows that the creep mechanism of soft mudstone conforms to the three stages of transient deformation, consolidation deformation, and stable deformation in consolidation creep, and shows obvious nonlinear characteristics. And the undisturbed sample, remodeled sample in the consolidation process produced a large degree of secondary consolidation creep, the maximum deformation can account for 59% of the total deformation. Numerical simulation results show that the fractional order Burgers model can better describe the nonlinear characteristics of the sub-consolidation creep; Model fractional order γ has a strong sensitivity to reflect the elasticity of the fitted curve and the nonlinear viscoelasticity after the stage, and fractional order  β  sensitivity is poorer than the viscoelasticity stage of the creep tendency to make a subtle response.
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Petrogenesis of  Cenozoic Basalts in Bohai Bay Basin:Geochemical and Sr-Nd-Hf-Pb Isotopic Evidences
Sun Jing, Jiang Leiyin, Hou Wen
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 531-545.   DOI: 10.13278/j.cnki.jjuese.20230173
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The Cenozoic basalts in the Bohai Bay basin are an important part of the Cenozoic basalts in the northeast of the North China craton. However, the limited exposure of basalt on the surface in the region hinders research of this place. In this study, we selected drill core samples from Liaohe oil field and analyzed their major and trace elements, and Sr-Nd-Hf-Pb isotopic compositions. The Cenozoic basalts from the Bohai Bay basin in this study are mainly tholeiite and trachybasalt. Their SiO2 and MgO contents are ranging from 49.08% to 50.70%, and 2.63% to 5.80%, respectively. Moreover, they are enriched in LREEs with highly fractionated LREEs and HREEs ((La/Yb)N = 7.96-11.61 and (Dy/Yb)N =1.71-1.84). These samples are enriched in high field strength elements (HFSE) and large ion lithophile elements (LILE), with evidently positive Nb, Ta and Sr and without Eu and Ce anomalies. The Sr, Nd and Hf isotope ratios of the whole rock are (87Sr/86Sr)i=0.704622-0.706581, εNd(t)=1.1-1.9, εHf(t)=1.6-4.6, respectively. The ratios of (206Pb/204Pb)i,(207Pb/204Pb)i and (208Pb/204Pb)i are 17.257 7-17.409 9,15.201 5-15.335 4 and 37.185 8-37.912 9, respectively. All these characteristics are similar to those of the oceanic island basalts (OIBs). The geochemical features, combined with petrographic observations and Sr-Nd-Hf-Pb isotopic compositions, suggest weak crustal contamination and fractional crystallization in their origin. In conclusion, the Bohai Bay Cenozoic basalts were derived from slight partial melting of asthenospheric mantle.
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Numerical Simulation of Groundwater Flow in a Karst Area with Conduits Generated by Gaussian Distribution
Liu Guodong, Du Chenghong, Hou Jie, Yang Mengxi, Chen Yu, Xie Yang
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 592-603.   DOI: 10.13278/j.cnki.jjuese.20220255
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In order to simulate the groundwater movement in the karst area more accurately, a karst hydrogeological unit in Pu’an County, southwest Guizhou Province was taken as the research area. The FEFLOW software based on the finite element method was employed to establish a numerical simulation model that couples karst conduits with equivalent porous media for groundwater flow in the area. Gaussian random distribution was employed to generate conduits for underground rivers controlled by the geological conditions such as fault, fissure, fracture etc. The water flow in the equivalent porous medium was described by the partial differential equation of the 3-D transient flow, and the water flow in the conduit was described by the Manning-Strickler equation. The water conducting fault is treated as a strong permeable block, the infiltration coefficient of rainfall in the catchment areas of the sinkhole is set to 1, and the spring is treated as a pumping well with a constant head in the numerical model. The simulation results showed that the determining coefficient of the relationship between the calculated water level and the measured water level at 25 observation wells can reach 0.998 5, and the Nash-Sutcliffe efficiency coefficient reaches 0.998 2, which is very close to 1. It shows that the groundwater simulation model based on these treatments reflects the characteristics of karst groundwater movement and has strong simulation ability, which can be used to improve the evaluation accuracy of karst groundwater resources.

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Optimization and Application of Organic Carbon Logging Prediction Models for Source Rocks: A Case Study of Chang 9 Member of Yanchang Formation in Ansai Area, Ordos Basin
Feng Ruoqi, Liu Zhengwei, Meng Yue, Jiang Liting, Han Zuowei, Liu Linyu
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 688--700.   DOI: 10.13278/j.cnki.jjuese.20230004
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Total organic carbon (TOC) mass fraction is an important index of source rocks evaluation. In order to evaluate the organic carbon of source rocks in Chang 9 Member of Yanchang Formation in Ansai area, southeast Ordos basin, firstly,this article  establishes w(TOC) models for quantitative prediction of well logging by applying the multiple regression model, the traditional Δlog R model, the improved Δlog R model and the generalized Δlog R model, based on core analysis of measured w(TOC) data and  the response characteristics of source rocks to different logging curves.  Secondly, by   analyzing and combining  these models,  the fitting superposition coefficient  extracted from the improved Δlog R model is applied  to the calculation of two generalized Δlog R models, and the application effect is  good. Finally, the four models are compared and optimized, and the most suitable quantitative prediction model for source rocks in the study area is proposed. The results show that the generalized Δlog R model considering the density factor has the highest accuracy, with an average relative error of 7.78%; The multiple regression  model   has the second highest accuracy, with an average relative error of 9.65%. Both of them can meet the accuracy requirements of quantitative prediction of w(TOC).
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P-Wave Traveltime Calculation Equation Based on Coefficient Matching and Integration Processing#br#
Wei Jian, Sun Xiang’e
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 337-344.   DOI: 10.13278/j.cnki.jjuese.20220309
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The traveltime formula based on Taylor expansion is a common method to calculate P-wave traveltime. The Taylor expansion is accurate only near the calculation point, and the inaccuracy of the traveltime approximation is further magnified in the medium of   transverse isotropy  with vertical  symmetry axis   (VTI). An improved method for calculating P-wave traveltime is presented in this paper. This method utilizes the 8th-order offset-traveltime equation based on the Taylor expansion, and the coefficient matching method is used to determine the coefficients of the series expansion. Then the integration processing is used to optimize the parameters. Finally, the 4th-order P-wave traveltime calculation method is formed  based on  coefficient matching and parameter integration. The test results for horizontal layered VTI medium models show that the proposed method has relatively small numerical errors and relatively good performance at the far offset. The experimental results for 3D VSP data show that after parameter adjustment, the method effectively analyzes the data, exhibiting stable performance at middle offsets and a certain advantage at far offsets. 
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Reliability Evaluation of Empirical Formula Between Shear Wave Velocity and Depth of Conventional Soils
Lu Dawei , Sun Yihan, Liu Hongshuai
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 546-557.   DOI: 10.13278/j.cnki.jjuese.20220271
Abstract19)      PDF(pc) (7322KB)(7)       Save

The statistical relationship between shear wave velocity and depth for conventional soil types (“Relationship Between Shear Wave Velocity and Depth of Conventional Soils”,by Liu Hongshuai, et al,power function and one-quadratic model equations in Tables 2 to 5) is a national empirical equation. It has become an important reference for testing and comparing empirical equations in many regions, but lacks a more systematic evaluation of reliability. Therefore, the statistical empirical equation of shear wave velocity and depth in typical domestic regions (Beijing, western Shandong, Chengdu,Tianjin, Changzhou and Wuhan) are selected to test the reliability of the empirical equation of the national shear wave velocity and depth of conventional soils. The results show that: The power function model predicts that the shear wave velocity increases with depth, which is consistent with qualitative understanding, while the quadratic model may exhibit unreasonable bending anomalies and should not be used. The prediction accuracy of the national shear wave velocity empirical equation varies significantly in different regions. In most regions, the absolute relative errors of the prediction for the vast majority of soil types are generally less than ±20%. The absolute relative errors are larger only within 20 m of the near-surface, with a maximum of about 40%. In a few areas, the absolute relative errors of the prediction are greater than 20%. It is recommended to prioritize the selection of shear wave velocity empirical formulas suitable for local conditions; When there is a lack of local equations and it is necessary to choose the national power function type empirical equations for shear wave velocity, it should be tested and confirmed by the local measured data before use; The shear wave velocity within the 20 m range is best determined by actual measurement, which helps to reduce the significant errors brought by the national shear wave velocity empirical formula. 

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Journal of Jilin University(Earth Science Edition)    0, (): 1244-1254.  
Abstract19)      PDF(pc) (35376KB)(17)       Save
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Calculation Model for Water Level and Settlement of  Soft Foundation Treated by Siphon Drainage#br#
Yuan Shuai, Wang Jun, Wu Zhaofeng, Shen Qingsong, Shu Junwei, Sun Hongyue
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 208-218.   DOI: 10.13278/j.cnki.jjuese.20220095
Abstract18)      PDF(pc) (9263KB)(31)       Save
Soft soil has the characteristics of poor permeability and low bearing capacity. The treatment of soft soil foundation is always a major problem in geotechnical engineering. With the characteristics of free power in drainage, the siphon drainage method can be applied in soft ground the treatment to improve the properties of the soil. Based on the discretized Theis well flow model and the nonlinear layered summation method of settlement, this paper constructs a water level and settlement calculation model considering the changes in permeability coefficient and compressive modulus by settlement with porosity as the core for the unique fixed-deck precipitation model of the siphon drainage method. The effect of the siphon drainage method in soft foundation treatment is analyzed from the aspects of soil permeability coefficient, drainage board spacing, and site size. The results mainly focus on the following three aspects. First, the calculation outcomes are compared with numerical simulation results and the reliability of the calculation model is verified. And the siphon drainage method can perform well in drainage and consolidation for soils of different permeability coefficients in Zhejiang coastal areas. Second, adjusting the spacing of drainage plates can significantly control the drainage consolidation time and the groundwater level. Third, the additional stress caused by drainage will extend into the soil as the site area increases, and for a 50 m×50 m site, the effective influence depth can reach 27.31 m below the surface, which is far beyond the limit of siphon lift. Therefore, the siphon drainage method will get a better effect in practical large-area soft soil foundation treatment.
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New Progress on the Study of Dinosaur Eggs in Laiyang, Shandong
Wang Qiang, Wang Xiaolin
Journal of Jilin University(Earth Science Edition)    2024, 54 (1): 38-45.   DOI: doi:10.13278/j.cnki.jjuese.20230320
Abstract16)      PDF(pc) (23066KB)(16)       Save
This paper briefly reviewed the history of the discovery and research of dinosaur eggs in Laiyang, Shandong Province, China. Combining with the new discoveries in the Laiyang basin in recent years, the composition of the Laiyang dinosaur egg fauna was revised from 4 oofamilies, 5 oogenera and 11 oospecies to 6 oofamilies and progress on the dinosaur eggs, 10 oogenera and 12 oospecies, 1 oofamily indet. and 1 doubtful oospecies. Compared assemblages with other dinosaur egg faunas in China, the Laiyang dinosaur egg fauna is a typical representative of the Late Cretaceous dinosaur egg fauna with diverse egg types and distinctive assemblage characteristics. At the same time, this combination also well reflects the high diversity of dinosaurs in the Wangshi Group of the Jiaolai basin during the Late Cretaceous. Further study on it will provide detailed paleontological evidence for further discussion on the paleogeography and paleoenvironment of Laiyang area in the Late Cretaceous.

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Influence of High Thermal Conductivity of Thermal Pipe in a Short Period of Subgrade Filling

Han Changyu, Zhao Haoting
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 570-580.   DOI: 10.13278/j.cnki.jjuese.20220265
Abstract16)      PDF(pc) (6947KB)(5)       Save

To study the influence of high thermal conductivity of thermal pipe on the temperature field of frozen soil under the subgrade in permafrost regions in the short term after subgrade filling, the temperature field change in the short term after subgrade filling was studied by numerical simulation method based on the coupling effect of water and heat. The results show that, due to the high thermal conductivity of the thermal pipe, the frozen front of the subgrade is concave along the thermal pipe in the short term after filling. Filling in June is easy to cause hydrothermal erosion at the slope toe and evaporation section;Filling in July, the lowest point of the freezing front is deeper than the embedded depth of the thermal pipe, which is the most unfavorable for the stability of the thermal pipe;Filling in August and September, the influence time of high thermal conductivity of hot rod is short. The effect of high thermal conductivity of thermal pipe on temperature field increases with the increase of filler temperature and thermal conductivity. In order to reduce the impact of high thermal conductivity of the thermal pipe in the short term after filling, construction from June to July should be avoided. During construction, the temperature of subgrade filler should be reduced as much as possible, and the thermal conductivity of the material can be appropriately reduced without affecting the cooling effect.


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Amplitude Extraction of Ground-Airborne Frequency-Domain Electromagnetic Signals Based on Synchroextracting Transform

Chen Liang, Zhang Tianyu, Wang Yanzhang, Zhou Haigen, Jiang Chuandong,
Journal of Jilin University(Earth Science Edition)    2024, 54 (2): 647-654.   DOI: doi:10.13278/j.cnki. jjuese.20230084
Abstract15)      PDF(pc) (8077KB)(12)       Save
The detection signal of the ground-airborne frequency-domain electromagnetic method (GAFDEM) is multi-frequency non-stationary signal, when extracting its amplitude using conventional Fourier transform methods, the resolution is poor. To solve the above problem, this paper proposes an amplitude extraction  method of ground-airborne  frequency-domain electromagnetic  signal  based on synchroextracting transform (SET). This method  performs SET on the electromagnetic data to obtain high-resolution time-frequency graph, and uses energy operator to make the energy of time-frequency spectral electromagnetic data more concentrated. At the same time, the greedy algorithm is used to realize the ridge extraction method to obtain the high energy band of the time-frequency graph. By filling in zero values in the ridges adaptively through autoregressive model, the endpoint effect problem caused by the window function is solved.  according to the complex value of the time-frequency-diagram at the ridge location, the variation of the amplitude of each frequency component with time is obtained, and the accuracy of the amplitude extraction of electromagnetic signals in the ground-airborne frequency-domain based on SET is investigated under different signal-to-noise ratios. Through calculation, when the signal-to-noise ratio  is greater than or equal to 10 dB, the average relative root mean square error  of the amplitude extraction result is less than 5%; When the signal-to-noise ratio  is less than 10 dB, the average relative root mean square error of the amplitude extraction result is less than 10%, achieving good extraction results. This method is applied to the GAFDEM delection  of the Huola Mountain tunnel project in Xinjiang, and the amplitude of each frequency component of the multi-frequency electromagnetic signal is successfully extracted. Compared with the method of extracting non-stationary signal amplitude using the Fourier transform, this method effectively improves the resolution of amplitude extraction results.
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