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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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Table of Content
26 May 2016, Volume 46 Issue 3
LA-ICP-MS Zircon U-Pb Dating and Hf Isotope Feature of Gabbro Xenolith and Its Geological Significance in Huziyan Basalt of Daoxian County, Southern Hunan Province
Kong Hua, Xu Mingzhu, Zhang Qiang, Tang Yuqiang, Zhao Jiajin
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  627-638.  DOI: 10.13278/j.cnki.jjuese.201603101
Abstract ( 448 )   PDF (6959KB) ( 364 )  

There are many gabbro xenoliths in Huziyan alkali basalt pipe in Daoxian County. The geochemical analysis of one gabbro dating sample show that it has high content of K2O, Fe2O3 and TiO2, compared with other gabbro samples, which suggests that the gabbro xenolith is product of crystallization differentiation of late-stage magma. The K* value (2KN/(TaN+LaN)) is 7.60 (>1), displaying the magma source experienced metasomatism. The Nb* value(2 NbN/(KN +LaN)) is 0.11(<1), implying crust contamination during basic magma intrusion. Zircon grains are chosen from gabbro xenolith for LA-ICP-Ms U-Pb dating and Hf isotope analysis. Zircon grains in the gabbro have clear crystallization zoning, the ratio of Th/U is 0.91~4.35, these features imply that these zircon grains have magmatic origin. The average age of 206Pb/238U is (201.50±0.53) Ma(1σ, MSWD=4.6), which represents the emplacement age of the gabbro xenolith. According to Hf isotope compositions, the calculated model age is 751 Ma, indicating the earlier crustal material gave contributions to source area, the values of εHf(t) are -0.88~4.45, in the figure of εHf(t)-t, the points of zircon grains lie in the area neighbored to evolution curve of chondrite mantle, which are different apparently from their Nd isotope geochemistry. Geochemical characteristics show that the deeply strong material exchange progress between deep crust and mantle in southern Hunan area. In Late Indosinian epoch, there occurred mantle uplift induced by partial extensions, which resulted in progressively the mantle melting to from gabbro magma. The gabbro magma underplated at the bottom of lithosphere and became one part of its consistent.

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Geological Characteristics and Hydrocarbon Accumulation of Ucayali Basin, Peru
Wang Jianjun, Li Haowu, Hu Xiangyu, Wang Qing, Wang Bin, Yang Cang
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  639-650.  DOI: 10.13278/j.cnki.jjuese.201603102
Abstract ( 373 )   PDF (8758KB) ( 289 )  

Based on the geological and hydrocarbon accumulation characteristics, there will be other types of hydrocarbon traps in Ucayali basin, such as extensional fault block, buried hill, reef, stratigraphic pinchout, channel sand and the footwall of thrust fault, besides the discovered thrust anticline/faulted anticline oil & gas fields. The in-sequence thrust anticline/faulted anticline will be the main traps. The traps were not well developed before the foreland orogeny, and the current hydrocarbon accumulations were mostly the product of secondary migration. The intrusion of freshwater mildly degraded most of oil in shallow reservoirs. Due to the separation of the Shira uplift, it was difficult for the hydrocarbon generating in the Western Sub basin to migrate into the Eastern Sub basin. The source rocks in the Eastern Sub basin was not buried deeply enough, the Ene Formation had limited distribution, the Ambo Group was gas prone, only limited liquid were generated in oil window, and the traps were growing, so the filling of traps were generally low. The active faults also are barriers for hydrocarbon parallel migration, the traps in the eastern side often have charge risk, and have little chance to form large oil accumulation. The Southern and Western Sub basins had good conditions for hydrocarbon accumulation, the thrust folds were well developed, the traps were continuously charging, and most likely to form gas fields. The foot wall anticlines of thrust faults will be the potential targets in Southern Sub basin. The Ene Sub basin is in low degree of exploration, and with perfect source rocks, so it has the potential to find large structural traps.

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Key Formations of the Permian Hydrocarbon Source Rocks and Oil-Source Correlation of well KD1 in Yecheng Depression of Southwestern Tarim Basin
Du Zhili, Zeng Changmin, Qiu Haijun, Yang Youxing, Zhang Liang
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  651-660.  DOI: 10.13278/j.cnki.jjuese.201603103
Abstract ( 340 )   PDF (5824KB) ( 315 )  

Permian is the main period for the accumulation of the hydrocarbon source rocks in the Yecheng depression of southwestern Tarim basin. Previous works hitherto have commonly treated simply the Permian oil-shales as a marine or lacustrine hydrocarbon source rocks, which have ignored an important fact that different formations of the Permian formed in different sedimentary environments, and show different sedimentary facies and have different oil and gas potentials. Based on the geological survey in Yecheng depression, combined with the drilling data, our results indicate that the key source units include Qipan and Pusige Formations. They are the main Permian source rocks in Yecheng (in the northwest) and Hetian (in the southeast) areas of the Yecheng depression. According to facies analysis and organic geochemical results, we interpreted that the Qipan Formation was deposited in a shallow marine shelf environment and distributed in Heshilafu-Momoke area of the northwestern Yecheng depression. The average thickness of source rock is more than 100 meters, the type Ⅱ organic matter have reached a high maturity evolution stage. In contrast, Pusige Formation was deposited in a lacustrine facies sedimentary environment and distributed in Pusha-Duwa area, the average thickness of source rock is more than 200 meters. It shows an average TOC content of 0.97% and type Ⅱ or Ⅲ organic matter which has reached the peak stage of hydrocarbon generation. Concerning the hydrocarbon potential of the two formations, Upper Pusige Formation is better than Qipan Formation. In order to trace the oil-source of a nearby commercial well KD1, we correlate the data sets of radiometric carbon isotope ratios and biomarkers of normal alkanes between the oil and different source rocks. Our results show that the oil trapped in the well KD1 comes from the Upper Pusige Formation source rocks. Combined with the comprehensive analysis of the petroleum system, we indicated that the most favorable exploration target in the region is the area of Fusha-Keliyang in the eastern Yecheng depression.

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Characteristics and Its Significance of Soft Sedimentary Deformations of the Upper Triassic Bagong Formation in Southeastern Qiangtang Block
Du Fangpeng, Wang Jianqiang, Niu Junqiang, Tan Furong, Yang Chuang, Yan Mingming
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  661-670.  DOI: 10.13278/j.cnki.jjuese.201603104
Abstract ( 340 )   PDF (8301KB) ( 237 )  

Within the Bagong Formation of Upper Triassic in Suoxian-Baqing, southeastern Qiangtang block, there are a large number of soft sedimentary deformation which formed in unconsolidated sediments. Their morphological characteristics mainly figured as pillow, ball, chain and curl. There are 7 layers of soft sedimentary deformation have been recognized along Zhadegai section with a total length of 100 m. Based on a detailed description and comparison of the deformation characteristics, these soft sedimentary deformations are classified as seismite, some deformations clearly show that the deformation is controlled by tensile stress. Seismite is the record of palaeotectonic activities in soft sediments. Densely dispersed soft sedimentary deformations in Bagong Formation shows that it was a tectonic active area at Upper Triassic. Compared with seismites in earlier Upper Triassic strata, we find that the tectonic activities are more intensely in Middle-Late Norian, which responds to ages of volcanic rocks in central Qiangtang block.

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Characteristics of Oil Shale of Oligocene Dingqinghu Formation and Its Geological Significance, Lunpola Basin
Du Baiwei, Xie Shangke, Dong Yu, Peng Qinghua, Zheng Bo
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  671-680.  DOI: 10.13278/j.cnki.jjuese.201603105
Abstract ( 411 )   PDF (3490KB) ( 423 )  

Oil shale of Oligocene Dingqinghu Formation orientating in NW-SE with about 50 km in length is discontinuously distributed. There are 18 to 22 oil shale layers ranging from 0.70 m to 2.00 m in thickness, of which the thinnest layer is 0.10 m and the thickest layer is 8.81 m. The results of industrial analysis show that Lunpola oil shale is a kind of high content of ash, medium to low oil yield and low calorific value. Organic carbon content of oil shale ranges from 2.40% to 20.23% with an average of 7.38%, indicating a relatively high abundance. Microscopic observations indicate that organic matter of oil shale is a kind of sapropel type kerogen. Vitrinite reflectance of kerogen range from 0.43% to 0.71% with an average of 0.52%, indicating that organic matter of oil shale underwent a stage of immature to low maturation. Abundant biomarkers, including n-alkanes, isoprenoid, terpanes and steranes from oil shale have been detected by GC and GC-MS. GC-MS characteristics of saturated hydrocarbon show that organic matter is characterized by aquatic phytoplankton. The characteristics of biomarkers and field observation reveal that oil shale forms in low-salinity anoxic semideep-deep lake environment. Phytoplankton and algae in the lake provide main origin of organic matters for oil shale formation, and stable structure and anoxic environment are beneficial for the conservation of organic matters.

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Features and Origin of Super-Large Oil Shale Deposit in Southeast Uplift of the Songliao Basin
Wen Zhiliang, Jiang Fuping, Zhong Changlin, Jiang Xuefei, Wang Guoqian, Qi Yan
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  681-691.  DOI: 10.13278/j.cnki.jjuese.201603106
Abstract ( 455 )   PDF (3964KB) ( 284 )  

The oil shale deposit is located in the southeast uplift area of Songliao basin, and belongs to a third-class structural unit of Songliao central fault depression in the Jilin-Heilongjiang geosyncline fold system. The studied area was mainly filled with Mesozoic Cretaceous clastic rocks. On the basis of the core observation and "Fischer" oil content test classification, it is concluded that the oil shale developed in dark and brown-black mudstone layers, which mainly distributed in the Qingshankou Formation and the Nenjiang Formation of Cretaceous. The oil shale layers correlation among boreholes and the lateral distribution characteristics show that the oil shale is layered in a large scale, stable distribution, and better continuity. The bulk organic geochemistry data shows the oil yield of oil shale is closely related to organic matter type and total organic carbon content. Meanwhile, oil shale has high ash content, it is low quality oil shale ores. Combining the oil shale features and sedimentary environment, it is concluded that the origin of the oil shale was sapropelic oil shale.

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Joint Optimization of Coal-Bed Methane and Tight Gas in the Upper Paleozoic of the Ordos Basin
Liu Peng, Wang Weifeng, Meng Lei, Jiang Shuai
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  692-701.  DOI: 10.13278/j.cnki.jjuese.201603107
Abstract ( 392 )   PDF (7182KB) ( 248 )  

Through a comprehensive analysis of accumulation conditions of coal-bed methane (CBM) and tight sandstone gas in the Upper Paleozoic of Ordos basin, it is conducted that the Upper Paleozoic is favorable to form coal-bed methane and tight sandstone gas resources. They have the same source rock, the tight sandstone reservoir and coal seam developed interbedded, which provide favorable conditions for the joint exploration and development of coal-bed methane and tight gas. Based on the accumulation conditions of both CBM and tight sandstone gas, this paper has established an evaluation parameter system, including coal thickness, Ro, gas generating intensity and tight gas reservoir thickness. Using the evaluation system, 5 blocks in Ordos basin were evaluated. The result shows that there are 3 target exploration areas and 2 favorable areas, which indicates a great exploration potential of CBM and tight sandstone gas resources in the Upper Paleozoic. The former areas are located in the east and west of Ordos basin, with thick coal layer, high intensity of gas generation, while the latter has a banding distribution in the northeast and northwest of the basin.

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Quantitative Explanation of Mechanism About Lower Wall of Antithetic Faults Accumulating More Oil-Gas than Upper Wall of Consequent Faults
Wei Danning, Fu Guang
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  702-710.  DOI: 10.13278/j.cnki.jjuese.201603108
Abstract ( 426 )   PDF (2693KB) ( 346 )  

To study the control effect of faults to oil-gas accumulation and distribution in oil-gas bearing basins, based on the study of mechanism and influence factors of faults lateral sealing, we made a quantitative explanation of mechanism about foot wall of antithetic faults accumulating more oil-gas than hanging wall of consequent faults. Antithetic faults and consequent faults both sealed oil-gas by fault rock and displacement pressure of fault rock in oil-gas migration direction, which were the main factors to influence its lateral sealing oil-gas ability. Under the similar conditions of faults buried depth and dip, layer lithology and dip, theoretically, the shale content of antithetic faults was larger than consequent faults, which mean that displacement pressure of antithetic fault rock in oil-gas migration direction was larger than consequent fault rock, and lateral sealing ability of antithetic faults was stronger than consequent faults, thus, the foot wall of antithetic faults accumulated more oil-gas than the hanging wall of consequent faults. We made an investigation on fault rock displacement pressure in oil-gas migration direction from foot wall of Banqiao fault under conditions of antithetic and consequent, in lower Es1 of Qikou sag. It indicated that, displacement pressure in oil-gas migration direction of antithetic fault rock was larger than consequent fault rock in foot wall of Banqiao fault in lower Es1, with stronger lateral sealing ability, which was favor of oil-gas accumulating in Es1, foot wall of Banqiao fault.

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Alteration Zoning and Geochemical Element Migration in Alteration Rock of Zhaotong Lead-Zinc Deposit in Northeastern Yunnan Mineralization Concentration Area
Chen Suihai, Han Runsheng, Shentu Liangyi, Wu Peng, Qiu Wenlong, Wen Dexiao
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  711-721.  DOI: 10.13278/j.cnki.jjuese.201603109
Abstract ( 432 )   PDF (4148KB) ( 275 )  

Wall-rock alteration is one of the important ore-prospecting clues in the Zhaotong lead-zinc deposit. Based on the studies of the alteration zoning and element migration in altered rock of the No.98 profile line in the 760 m level of this deposit, we discussed the relationship between the alteration and the mineralization. There develops obvious hydrothermal alteration zonation, from the center of the ore body to outside, alteration gradually weakened. In the altered center, the pyritization is most intensive, followed by dolomitization and calcitization, and silicification is the weakest, and the pyritization is closely related to mineralization. Far away from the ore body, pyritization weakened gradually, calcitization and dolomitization increased gradually. The intensive pyritization and the intensive pyritization-calcitization-silicification coarse-grained dolomite alteration are important prospecting clues. From fine-grained dolomite zone to the intensive pyritization zone, such elements as Ge, Ag and Cd, which have a close relationship to Zn-Pb of ore-forming, migrate in as a whole. Meanwile, both iron and Pro iron elements markedly enriched accompanying by the ore-forming fluids elements, which indicates that different alteration facies were reformed by the hydrothermal fluids. The index of alteration(IA) has the positive correlation with the alteration intensity.

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Critical Geological Issues About Ore-Prospecting Breakthrough of Pb-Zn-(Ag) Polymetallic Deposit in Northeast Yunnan
Tang Zhong, Li Wenchang, Wang Changbing, Ming Tianxue, Li Rong, Bao Congfa, Wang Jue, Li Yongping
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  722-735.  DOI: 10.13278/j.cnki.jjuese.201603110
Abstract ( 316 )   PDF (3361KB) ( 317 )  

Studies of the past few decades of research data and exploration experience about Pb-Zn-(Ag) polymetallic deposit in northeast Yunnan indicate that there are several critical geological issues about prospecting breakthrough difficult to be understood and resolved. According to the "Geological Body-Structure-Mineralization" prospecting prediction method, the metallogenic geological body, ore-forming structure and mineralization characteristic indications can directly influence all geological features of the deposit. However, combined with previous opinions and the latest information, we proposed that there are two main kinds of Pb-Zn deposit discovered in the area, strata-bound and structure-controlling deposits. The metallogenic geological body was depression basin of plateau land system, and main ore-controlling structure were some secondary fractures caused by SN-NW-NE trending deep fault zone. It is considered that the genesis of deposit is closely related to sedimentary and epigenetic hydrothermal transformation, the mineralization ages of these deposits are mainly in the Late Triassic, the metallogenic material mainly originated from carbonate formation of Sinian System, and their metallogenetic mechanism can be concluded as followings, the subduction of the Paleo-Tethys ocean to the southwestern edge of the Yangtze plate caused the recycling action of hot, gas and hydrothermal fluid in intracontinental basin, which resulted in consist transforming, extraction and enrichment of metallogenic elements, and led to the polymetallic mineralization.

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Petrogenic Age and Magma Source of Granite Porphyry in Lishanling Porphyry Cu Deposit in Changshan Area, Zhejiang Province
Wang Keqiang, Zhang Dehui, Zhu Yudi, Fu Fen, Yin Xianbo, Wang Chensheng
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  736-748.  DOI: 10.13278/j.cnki.jjuese.201603111
Abstract ( 376 )   PDF (5055KB) ( 348 )  

Zhejiang is well known for its abundant non-metallic mineral resource, whereas is lack of research data on metallic deposits, especially on the porphyry deposits. The Lishanling porphyry Cu deposit has been chosen as a study object, the SHRIMP zircon U-Pb dating is applied to restrict the emplacement age of Lishanling granite porphyry. Sr-Nd isotope tracing is completed to study the origin of granite porphyry. The research result not only can enhance the study on ore genesis of porphyry deposits in Zhejiang, but also is vital important for further ore exploration in western Zhejiang. The Lishanling porphyry Cu deposit is located in the east of Qinzhou-Hangzhou suture zone, and the copper mineralization occurs within the granitic porphyry. The ore-bearing porphyry is classified as the S-type granite with high silica, alkaili content, strong fractionation, and peraluminous characteristics. In the chondrite-normalized diagram, the REE patterns lean to the right, appears as a seagulls, the enrichment of LREE and negative Eu anomalies are abvious. The porphyry is rich in Nb, Ta, Zr, Hf, Ti, Y, Yb; and depleted of LILEs such as Sr and Ba. Zircon SHRIMP U-Pb age of ore-bearing granite porphyry is (131±2) Ma, which proves that the porphyry was resulted from the Early Cretaceous tectonic-magmatic activity and formed in the tectonic background of lithospheric thinning in Eastern China. The ore-bearing porphyry has relative high value of ISr(0.679 95 to 0.721 08) and low εNd(t) value (-8.4 to -5.8), with the average value of 0.701 14 and -6.7 respectively. The ore-bearing granite porphyry mainly origin from crustal rock with a small amount of mantle contamination, which can be proved by the Sr-Nd isotopic characteristics.

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Geochronology, Geochemistry and Geological Significance of Granite Porphyry in Hutouya Polymetallic Deposit, Qimantage Area, Qinghai Province
Zhang Xiaofei, Li Zhiming, Jia Qunzi, Song Zhongbao, Chen Xiangyang, Zhang Yulian, Li Dongsheng, Shu Xiaofeng
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  749-765.  DOI: 10.13278/j.cnki.jjuese.201603112
Abstract ( 404 )   PDF (11600KB) ( 228 )  

Magmatic intrusions widely distributed in Qimantage area of Qinghai Province, are mostly located around NW-extending regional structure. The granite porphyry in Hutouya polymetallic deposit occurred in the joint position of the E-W extending and northwest-extending structures. Phenocrysts mainly include quartz, plagioclase, K-feldspar, biotite and amphibole.This paper reported major, trace, rare earth elements composition and LA-ICP-MS zircon U-Pb dating result about the granite porphyry. Simultaneously, geochemistry and petrography of the ore-hosting rock in the Hutouya polymetallic deposit are studied. The granite porphyry is characterized by high silicon, high potassium and low aluminum, and belongs to the high-K calc-alkaline series metaluminous-peraluminous granite. Trace elements are enriched in LILEs, depleted in HFSEs, and with Ba, Sr, Nb negative anomaly characteristics. In the REE partition diagram, the porphyry is in seagull form, having Eu negative anomaly character. The granite porphyry can be classified into the A2-subtype granite. The granite in the Hutouya ore district has the common geochemical charactersistics, genetic type, magma source and forming environment with the granite porphyry, which indicates that they formed the granitic complex. The complex was originated from the common magma source and emplaced in the extensional environment occurring after the post-collision transitional period from compression to extension of East Kunlun orogenic belt. LA-ICP-MS Zircon U-Pb dating of the granite yielded (232.7±1.8) Ma(MSWD=1.3, n=22), representing the fact that the East Kunlun was in the end stage of the intracontinental orogeny during Indosinian. Large-scale magmatism led to the Indosinian mineralization in the Qimantage area.

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Mesozoic Volcanic Rocks in Yilehuli Area: Zircon U-Pb Ages and Their Constraints on the Magmatic Events
Yin Zhigang, Wang Wencai, Zhang Yuelong, Wang Yang, Han Yu, Cao Zhongqiang, Zheng Bei
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  766-780.  DOI: 10.13278/j.cnki.jjuese.201603113
Abstract ( 384 )   PDF (7926KB) ( 216 )  

The Mesozoic volcanic rocks in Yilehuli area consist of andesites, trachy-dacite, rhyolites, fine ash tuff rhyolitic volcanos and rhyolitic vitric tuffs.Zircons from these Mesozoic volcanic rocks has obvious oscillatory zoning, are of euhedral-subhedral shapes and high Th/U ratios (0.30-2.56), implying their magmatic origin.The mean U-Pb age of zircons in volcanic rock from the Tamulangou Formation is (161.0±1.0)Ma(n=22), suggesting the volcanic rock was formed in the Middle Jurassic; mean U-Pb ages of zircon from the volcanic rock in the Manketouebo Formation is (157.8±2.3)Ma(n=24), suggesting these volcanic rock in the Manketouebo Formation was formed in the Late Jurassic; U-Pb age of zircon grains from two volcanic rock samples in the Manitu Formation are (154.0±2.0)Ma(n=23) and (151.7±1.4)Ma(n=25) respectively, suggesting the volcanic rock in Manitu Formation was also formed in the Late Jurassic;mean U-Pb ages of zircon grains from volcanic rocks in the Baiyingaolao Formation are (124.1±1.1)Ma(n=25) and (125.1±0.7)Ma(n=23) respectively, suggesting those volcanic rocks in the Baiyingaolao Formation formed in the Early Carboniferou. The dating results of captured zircons show that the Precambrian (D4554.10:774 Ma), Caledonian (PM008TC42.17:472 Ma), Indosinian (D0350.15:214 Ma, D0350.16:210 Ma) magmatic events had taken place in the area, which is consistent with the zircon U-Pb dating results from the surrounding rocks in basement.

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Discussion on the Relationship Between Pan Pacific Plate Movement and Mesozoic Geological Evolution of Eastern Chinese Continent
Yang Haibin, Tian Xiaobo, Bai Zhiming, Zhang Zhongjie
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  781-797.  DOI: 10.13278/j.cnki.jjuese.201603114
Abstract ( 484 )   PDF (4946KB) ( 451 )  

This paper aims to reveal the relationships between the temperal-spatial distribution of geological recordings, like magmatism, structure and sedimentary basin, and the movement of Pan Pacific plate which intensively influenced the Eastern Chinese continent. As a consequence, variation of plate subducting angle, velocity and direction can produce a great impact on the continent overlying. The Eastern Chinese continent, consisting of Northeast China (NEC), North China(NC) and South China(SC), all were influenced by the Pan Pacific plate subduction on the eastern borde. Due to their various inherent properties, different plates had experienced different geological evolution. Based on discussion on some phenomena characterized as full of anomalies, some conclusions can be drawn for further test. Firstly, through mechanical analysis of possible triple junctions ever existing in eastern China continental frontier, it is suggested that the TTT, TTR or TFT modes should work there, rather than the simplified stable passive continental boundary. Secondly, the origin of west-east distribution of magmatism in central SC might call the ridge of Farallon and Izanagi plate as a reference. The NWW-extending ridge expanding of Izanagi and Pacific could result in the backward movement of plate blocks from the Late Jurassic to Early Cretaceous. Thirdly, few evidence supports the subduction ever took place in the eastern NC, which leads to the hypothesis that the Tanlu fault, the inherent weak part of NC, could have performed as other continent margin, which can be indicated by the strong coupling of plate motion and the corresponding activities of Tanlu fault in Jurassic and Early Cretaceous, instead of plate subduction under NC.

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Experimental Study on Mechanical Properties of Frozen Soft Rock of Cretaceous Formation in Bojianghaizi Mine
Zhu Jie, Xu Ying, Li Dongwei, Chen Junhao
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  798-804.  DOI: 10.13278/j.cnki.jjuese.201603201
Abstract ( 366 )   PDF (2569KB) ( 315 )  

Triaxial compression tests at different temperatures(-20~20℃) were carried out for medium sandstone and mudstone of cretaceous formation in Bojianghaizi mine.The results show that between -20~20℃ the peak strength and modulus of elasticity of the soft rock increase with temperature decreasing and confining pressure rising. The variation degree of peak strength of medium sandstone is obviously higher than that of mudstone, that is to say the former has higher sensitivity to temperature. At the same time, the peak axial strain declines with temperature decreasing.Furthermore, the peak angle of internal friction and cohesion increase with the drop of temperature, and the increase of the shear strength index mainly reflects in the cohesion.Through the analysis of experiment results, mechanical properties and law of cretaceous frozen soft rock in the different confining pressures and low temperatures are recognized, which can provide reliable basis for the design and construction of mine with freezing method in the western region.

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Pile-Soil Interaction Mechanism and a Method to Determine Vertical Bearing Capacity of Prestressed Concrete Pipe Pile
Wang Changming, Chang Gaoqi, Wu Qian, Li Wentao
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  805-813.  DOI: 10.13278/j.cnki.jjuese.201603202
Abstract ( 481 )   PDF (2590KB) ( 289 )  

In order to research further on the pile-soil interaction mechanism and the methods to determine the vertical bearing capacity of prestressed concrete pipe pile, taken three projects of the prestressed concrete pipe pile in Changchun area as examples, the squeezing effect of pile to soil and the resistance of pile tip resistance are simulated numerically and tested by loading tests. It is shown that the side friction and the tip resistance are together produced to support the top load of pile in process of pile pressed into subsoil, and thus cause compressional deformation in the subsoil around the pile and near the end of pile. With increasing in depth, the top load of pile will increase gradually, and the bigger diameter of pile is the larger top load is. The proportion of tip resistance to pile bearing capacity tends to decline in regular with increasing depth of pile. According to the relationship between the proportion of pile tip resistance to single pile bearing capacity and the depth of pile, a new method to determine the bearing capacity of single pile is suggested in this paper. The method is feasible and applicable in Changchun area as the ratio of its calculation values to the results from empirical formula is between 0.57 and 1.26.

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Quantitative Assessment for Impacts of Precipitation Variation and Runoff-Yield Change on Fenhe River Runoff
Niu Junyi, Wu Zening, Jia Hu
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  814-823.  DOI: 10.13278/j.cnki.jjuese.201603203
Abstract ( 325 )   PDF (1643KB) ( 276 )  

Quantitative analysis of the sharp decrease of runoff is an urgent problem to be solved in the water resources sustainable utilization and management in Fenhe basin. Firstly, double cumulative curve of precipitation and runoff was applied to divide the evolution process of runoff yield mechanism in the basin into two periods of 1956-1973 and 1974-2008, and the precipitation series of the basin was divided into wet, normal and dry state by means of anomaly method. On the basis of the analysis mentioned above, the multivariate dynamic regression model was established between the runoff of the current year, the precipitation of the current year and the previous year. And the multivariate dynamic regression model was applied to the quantitative assessment for the impact of the precipitation variation and runoff-yield change on Fenhe River runoff. The result showed that, under the runoff-yield condition of Fenhe basin during 1956-1973, precipitation changes caused the annual runoff volume of Hejin hydrologic station reduced by an average of about 22.71%, while under the runoff-yield condition during 1974-2008, precipitation changes in the normal and dry state years caused the annual runoff volume of Hejin station decreasing by an average of about 18.95%; under the condition of precipitation in the normal and dry state years from 1956 to 1973, the runoff-yield change of Fenhe basin led to a decrease of runoff volume about 47.11%, while under the condition of precipitation during 1974-2008, the runoff-yield change of Fenhe basin led to a decrease of runoff volume about 55.20%.

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Hydrogeological Conditions Control of Shale Gas Exploration
Zou Youqin, Liu Li, Li Hongqing, Yan Chun, Zeng Masun, Lan Yingying
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  824-830.  DOI: 10.13278/j.cnki.jjuese.201603204
Abstract ( 316 )   PDF (2080KB) ( 199 )  

By comparing the similarities between constant pressure exploration of shale gas and fixed drawdown exploitation of confined groundwater, through the establishment of correspondence indicators between the two, exampled by typical shale reservoir parameters from the USA Barnett shale annual production variation pattern, studying from a hydrogeology perspective, a hydrogeological conceptual model was established to stimulate shale gas exploitation by using GMS(groundwater modeling system) software. The result of model identification and verification shows that, among the 11 fitting values, 6 relative errors are within 5%, 4 relative errors are within 10%, and only 1 is approximately 20%, which indicates that the fitting results are quite desired; it also illustrated that hydrogeological methods in shale gas exploitation are reasonable, and it also showed that in the process of mining, shale gas production is composed of free gas and adsorbed gas, after the entire collection of free gas, the gas yield is supported by the desorbed gas basically; the desorption gas will be re-adsorbed. If there exist fractures in the overlying layer, the number of years and yield for mining decrease along with the fracture increasing. If the fractures in the overlying layer increase as many as 25%, 50%, 75%, and 100% of microfractures zone (Ⅱ/Ⅲ zone), the number of years for mining will decrease to 6 years, 4 years, 2 years, and 1 year accordingly; in different circumstances, with the same mined year, the yield decreases accordingly too. In each case, the ratio of the annual output to that of the original decreases accordingly too. When the boundary conditions change, the lateral boundary (the lower boundary or the right boundary) is set to permeable fault respectively, whether its permeable abilities are 25%, 50%, 75% or 100% of the microfractures zone (Ⅱ/Ⅲ zone), the fixed drawdown (constant pressure) mining conditions can't be met. Thus, the boundary conditions have more influence on shale gas with respect to the overlying/underlying rock. The sensitivity analysis showed that the change of source and sink terms has much greater influence on the gas yield than that of permeability.It is concluded that to promote by all means the desorption of the adsorbed gas is crucial, even determinable, to shale gas production in a certain degree of fracturing. Some suggestion is proposed to exploit shale gas.

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Shallow Groundwater Hydrogeochemical Evolution Process and Controlling Factors in Plain Zone of Guanghan City
Chen Meng, Wu Yong, Gao Dongdong, Chang Ming
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  831-843.  DOI: 10.13278/j.cnki.jjuese.201603205
Abstract ( 334 )   PDF (3199KB) ( 437 )  

Four methods, including mineral weathering system analysis, correlation analysis, principal component analysis and inverse hydrogeochemical simulation by PhreeQC are used to analyse the chemical composition, identify hydrogeochemical evolution processes and controlling factors, then complete analyzing quality and spatial temporal distribution of shallow groundwater in the plain of Guanghan City, which provides basic data for developing and utilizing groundwater resources exsisting in urban and rural planning process. The analysis showes that Gibbs plots indicate that the groundwater hydrochemical characteristics are dominated by rock weathering, the weathering processes produce ions and then secondary minerals undergo hydrolysis; aluminosilicate minerals of water samples tend to dissolve gradually in the mineral weathering system stability diagram; carbonate minerals are saturated. PhreeQC inverse hydrogeochemical simulation results show what mainly happen in the water flow path simulation are the dissolution of calcium montmorillonite and K-feldspar, the precipitation of kaolinite, quartz and albite, and the cation exchange adsorption between Ca-Na2; The analysis of ion correlation and principal component analysis verifies that leaching, evaporation and concentrating, and cation exchange adsorption are the main cause of hydrochemical process and mineral composition in the shallow groundwater. The groundwater quality in the study area generally will not cause adverse effects on human health.

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Site Selection for Offshore CO2 Geological Storage and Its Suitability Evaluation: A Case Study of Yuhuan Power Plant
Diao Yujie, Zhang Senqi, Li Fucheng, Gao Shiwang, Wang Xiaolong, Jia Xiaofeng
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  844-854.  DOI: 10.13278/j.cnki.jjuese.201603206
Abstract ( 387 )   PDF (4995KB) ( 357 )  

A large number of power plants, cement plants, refineries and other CO2 sources locate in East China and eastern coastal areas. However, deep saline aquifers for large scale CO2 storage projects lack because of long distance from onshore large and medium-sized sedimentary basins. Taking Yuhuan power plant as an example, we carried out an evaluation on suitability of Oujiang depression in the basin of East China Sea shelf for CO2 geological storage. Based on geological study, potential reservoirs and caprocks are preliminarily delineated, and then geological safety and economic suitability are studied. Using formulas proposed by CSLF (carbon sequestration leadership forum), the CO2 storage potential per square kilometers for selected reservoirs was evaluated too. And based on the index system consisting of reservoir, geological safety and economic suitability, we carried out suitability evaluation for site selection in deep saline aquifers using the GIS multi-information fusion. Finally, two sites located in west secondary Lishui depression are suggested for Yuhuan power plant. This paper could provide guidance for offshore CO2 geological storage site selection in East China and eastern coastal areas.

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Prediction Models of Deep Hydrothemal Geothermal Potential Areas Based on GIS: A Case Study of Western Anatolia, Turkey
Zhang Yanjun, Yu Hai, Li Jianming, Yu Ziwang, Zhang jianing
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  855-864.  DOI: 10.13278/j.cnki.jjuese.201603207
Abstract ( 342 )   PDF (4822KB) ( 310 )  

Geothermal exploration involves a high degree of uncertainty and financial risk, and requires reliable prediction model to identify geothermal potential areas. Mathematical prediction models were established by integrating five factors that closely related to geothermal, including earthquake epicenter, lineament, Bouger gravity anomaly, magnetic anomaly and infrared remote sensing; and the advantages and disadvantages of models were compared by an example of western Anatolia, Turkey. Index overlay(IO) and weights of evidence(WofE) were applied to establish geothermal resource potential maps, respectively. Success indices suggest that the predicting outcomes of WofE are more reliable than IO. The very favorable area and the favorable area are about 26 529 km2, accounting for 31.14% of total area, including 39 geothermal resource potential sites, which is 50.65% of the total sites.The potential areas in the WofE map are Ayd?n, Denizli, Manisa and Bal?kesir, of which the former two have been explored and exploited. This study is helpful to locate geothermal potential areas and reduce financial risk in the process of geothermal exploration.

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Scenario Simulation on Changing Pattern of Land Use for Wetland in the West of Jilin Province
Liu Yan, Liu Jiping, Sheng Lianxi
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  865-875.  DOI: 10.13278/j.cnki.jjuese.201603208
Abstract ( 317 )   PDF (5529KB) ( 243 )  

Wetlands have important eco-environmental functions in the west of Jilin Province that located in ecologically fragile zone. In recent years wetlands changed significantly in the west of Jilin Province because of more anthropogenic interference. In order to strengthen wetland functions and improve regional eco-environment, this paper simulated wetland spatial pattern in 2020 by using CLUE-S model, and set up three scenarios of wetland change, including 1) natural development scenario, 2) planning priority scenario and 3) ecological construction priority scenario based on the analysis on wetland change in the west of Jilin Province from 2000 to 2010. This paper also analyzed the characteristics of wetland spatial distribution and evaluated landscape anti-interference abilities in three different scenarios, and made clear the differences among three wetland patterns and explored reasonable wetland patterns. The results showed that average correct rate of predication on all types of land in the study area was 84.54%, with κ index of 0.83, which indicated that CLUE-S model can well simulate land-use changes in 2020, especially for marshes, waters, and residential land. Wetland patterns in three scenarios have obvious differences. The centroids of marshes and waters respectively tended to move to southwest and southeast in three scenarios, while the centroid of paddy fields of scenario 1 moved to northeast and that of scenario 2 and 3 moved to south. Marshes and paddy fields of scenario 3 have a stronger assemblage than those of scenario 1, while waters of scenario 1 have a stronger assemblage than those of scenario 3. From 2010 to 2020, in scenario 1, the landscape interference indexes of all types of wetlands all increased gradually, while in scenario 2 and scenario 3, the landscape interference indexes of marshes and waters all show a drop trend, especially the decrement in scenario 3 is the maximum, which indicated that wetland landscape has a stronger anti-interference ability when ecological construction priority scenario is implemented.

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Application of Minimum Noise Fraction on Noise Removal for Airborne Electromagnetic Data
Zhu Kaiguang, Li Yue, Meng Yang, Wang Lingqun, Xie Bin, Cheng Yuqi
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  876-883.  DOI: 10.13278/j.cnki.jjuese.201603301
Abstract ( 451 )   PDF (5958KB) ( 220 )  

There is still residual noise in time-domain airborne electromagnetic data after preprocessing, which will affect the recognition of target. We proposed an approach to remove the residual noise based on minimum noise fraction. A set of noise-contaminated data will be linearly transformed by using the rotation matrix to the minimum noise fraction components, which are arranged in signal to noise ratio (SNR) from big to small. We use the minimum noise fraction components with the bigger SNR to reconstruct the electromagnetic data for separating the signal and noise.The experiment with the simulation data test shows that the minimum noise fraction can not only effectively suppress the noise of the profile of later channels, but also accurately identify the information of the target. The SNR has improved by 11.28 dB compared with the survey-line filtering. The noise level for the field data is reduced from ±50 nT/s to ±10 nT/s after noise removal.

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3D Finite Element Forward Modeling of Five-Pole Longitude Induced Polarization Sounding
Liu Haifei, Liu Jie, Gao Han, Guo Rongwen, Tong Xiaozhong, Ma Changying
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  884-892.  DOI: 10.13278/j.cnki.jjuese.201603302
Abstract ( 335 )   PDF (1766KB) ( 263 )  

The authors develop a three-dimensional(3D) finite element forward modeling method for five-pole longitude induced polarization (IP) soundingin this paper. Boundary value problems of the secondary potential field are derived from that of the primary potential field with the three-point current sources, it also proves the corresponding variation equation saccording to the boundary value problem of the secondary potential field. Then we solved the variation equations of the secondary potential field using a finite element method (FEM) based on a 3D continuous model of the electrical conductivity, specifically for five-pole longitude array. Finally, we calculate the induced polarization sounding curve with the five-pole longitude array based on the horizontal layered medium, the results show that the maximum relative error is less than 0.25% and the total computational time is about 18 seconds. Three examples indicate the accuracy and efficiency of the proposed algorithm, which will facilitate the application of the five-pole longitude IP sounding for complex geoelectrical structure, understanding of the IP sounding curve anomaly, and further carrying out the inversion.

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Quantitative Interpretation Method of Small-Scale Sedimentary Facies Based on Strata Slice
Zhang Zhaohui, Liu Huaqing, Su Mingjun
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  893-899.  DOI: 10.13278/j.cnki.jjuese.201603303
Abstract ( 299 )   PDF (3785KB) ( 213 )  

Traditional waveform classification and reflection structure attribute mapping based on seismic data are used for the recognition of large scale (larger than λ/4) and the qualitative sedimentary facies, however, they cannot satisfy the requirements for exploration of the thin layer (less than λ/4). Strata slice is the key technology of seismic sedimentology, it is found that the deposit body in seismic data is easier to identify in horizontal imaging than vertical direction, it also clearly describes the distribution features and provides the reliable data for small-scale (usually less than λ/4, even the level of single layer) sedimentary facies analysis. Scale size mainly depends on the sampling ratestrata slice, the higher the sampling rate is, the smaller the target size is. Firstly, based on the extraction, optimization, and fusion of sedimentary microfacies attributes at the well points, the proposed method gets the feature attributes data of sedimentary microfacies, which is used for making strata slices, then we process the strata slices according to the rule of "what you see is what you want!" that includes image segmentation and smoothing boundary lines. Finally, we label the segmentation regions using the mathematical mapping relationship among sedimentary microfacies, feature attributes, and image characteristics of strata slices. In this paper, the interpretation method of sedimentary facies based on seismic data is developed from qualitative to quantitative and from large scale to smaller scale. The boundary lines of sedimentary facies are more precise than well-control extraction, it provides the data basis for reservoir prediction and well placement inexploration and development stage.

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Deep Structure Based on Seismic Array Observations in Daqing Area
Kang Jian, Wei Qinghai, Zhou Lin, Gao Yan, Zhang Yonggang, Gao Feng
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  900-910.  DOI: 10.13278/j.cnki.jjuese.201603304
Abstract ( 374 )   PDF (7731KB) ( 223 )  

We combine the data from the mobile seismic array in Suifenhe-Manzhouli geoscience transect with those from the permanen tstations recorded from June, 2009 to May, 2011, the information are used for calculating the three-dimensional P-wave velocity structure of upper mantle in the study area according to body wave travel-time tomography, which is based on the limited frequency method.The proposed to mography method includes double-station phase velocity of Rayleigh wave and phase velocity of background noise, the three-dimensional S-wave velocity structure in the study area can be calculated by using the inversion. Finally, the two methods obtain the three-dimensional velocity distribution in Daqing area. The results show that the crust of Songliao basin is thin and the crusts of Da Hinggan Mountains and Xiao Hinggan Mountains around the Songliao basin are thick. The crust often has low velocity anomaly in the Songliao basin, the crust-mantle boundary and upper mantle show high velocity anomaly compared with the neighboring regions. The reason of local high-speed anomalies may be due to the rise of mantle material. Velocity anomalies usually show NS or NNE, which may be related to the impact of regional faults on the upper and middle crust.

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Seismic Denoising Technique Based on Surface Wave Modeling and Curvelet Transform
Cui Yongfu, Li Guofa, Wu Guochen, Shang Shuai, Zhao Ruirui, Luo Lili
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  911-919.  DOI: 10.13278/j.cnki.jjuese.201603305
Abstract ( 588 )   PDF (7881KB) ( 436 )  

Surface wave is the main noise inseismic land data. The conventional FKK method with crossing trace gather cannot protect useful information with low frequency. In this paper, we propose a method based on surface wave modeling and curvelet transform to suppress surface waves. The proposed method includes two steps.In the first step, we use surface wave modeling to suppress base order, first order and second order surface wave. In the second step, the curvelet transform is used for residual surface wave removal.Results from filed data examples how that the proposed method can protect useful signals in low-frequency range while removing surface waves, the signal to noise ratio can be improved, and the work flow provides a surface wave suppression method with relative amplitude preserving, especially in the study area.

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Factor Analysis of Seismic Modeling with Topography Based on a Fully Staggered Body-Fitted Grids
Li Qingyang, Li Zhenchun, Huang Jianping, Li Na, Su Zairong
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  920-929.  DOI: 10.13278/j.cnki.jjuese.201603306
Abstract ( 376 )   PDF (2450KB) ( 369 )  

Finite-difference forward modeling method with body-fitted can accurately simulate wavefields in presence of topography, meanwhile, the computational efficiency is relatively high. Therefore, it is a prospecting method for dealing with the western complex surface. The collocated-grid and standard staggered grid are often used to solve wave equation. However, they show many problems when the above two grids are extend to body-fitted grids. By introducing the fully-staggered grid to curvilinear coordinates, the proposed method can avoid not only the interpolation error when standard staggered grid are used, but also the high-frequency oscillations with the collocated-grid. Thus, it can improve the simulation accuracy and reduce the complexity of the algorithm degrees. To satisfy the free surface boundary condition, we use the traction image method to calculate the velocity components, the method also uses the velocity of free boundary conditions with compact staggered difference format to update the stress components. Model tests show that the proposed method can obtain the good results. And then, we mainly study the influence factors of forward modeling algorithm by a fully staggered body-fitted grids, such as, the orthogonality of grids, the grid spacing change, and the skewness of meshes.Finally, we obtain some conclusions as follows:the algorithm is not sensitive to the orthogonality of grids;the grid spacing changing can lead to false reflection;the result of simulation is not affected by the skewness of different types of grids.

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Gas-Bearing Logging Features and Quantitative Evaluation for Tight Sandstone Reservoirs
Pan Baozhi, Jiang Bici, Liu Wenbin, Fang Chunhui, Zhang Rui
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  930-937.  DOI: 10.13278/j.cnki.jjuese.201603307
Abstract ( 473 )   PDF (7433KB) ( 199 )  

Tight sandstone reservoirs always show the characteristics, such as, low porosity, low permeability, and strong heterogeneity.The logging response characteristics corresponding to gas-bearing reservoir is very complex, so that the identification and evaluation of gas are difficult and it always shows multiple solution. Conventional well log is used for qualitative evaluating the gas-bearing characteristics.However, the classification model in intelligent recognition method still belongs to qualitative evaluation, which makes the traditional well log difficult to quantitatively evaluate gas.We use the core, geology, gas testing and conventional logging data to analyze the gas characteristics by cross-plot method and build two indexes, which can be used for qualitatively evaluating the gas containing. The workflow includes the generalized regression neural network (GRNN)that reconstructs gas and water indication curve to quantitatively evaluate the gas containing. Finally, we used the index method and GRNN curve reconstruction method to evaluate the tight sandstone gas in the Sulige area.The results show the good application effects.

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Lithologic Information Extraction from ASTER Remote Sensing Data Based on Spectral Ratio Method
Chen Shengbo, Yu Yafeng, Yang Jinzhong, Wang Nan, Meng Hua
Journal of Jilin University(Earth Science Edition). 2016, 46 (3):  938-944.  DOI: 10.13278/j.cnki.jjuese.201603308
Abstract ( 390 )   PDF (3663KB) ( 315 )  

At present, the spectral bands ratio method can be used for extracting and recognizing the lithologic information.In this paper, the gabbro, peridotite, olive gabbro, and diorite in the north slope of north orogenic belt in Xinjiang are selected as the research object, we deeply analyze the difference of the four kinds of lithology in VNIR-SWIR spectrum domain. On account of the -OH absorption characteristic of the gabbro, olive gabbro, and peridotite diorite in the near 2 300 nm spectrum, we establish the relative absorption depth data of band 8, which is called RBD8.On the strength of the weak absorption characteristics of the olive gabbro, peridotite diorite and between 400 nm to 700 nm in the spectrum, we establish the RI21 ratio index to reflect the abundance of the four kinds of lithologies, which contain Fe3+. Because of the wide and strong absorption band of the four kinds of lithology near 1 100 nm in the spectrum caused by Fe2+, we establish the ratio index, which is called as RI54 to estimate the content of Fe2+.Using ratio indexes RBD8, RI21 and RI54 to enhance the image, respectively, we enhance image for the RGB color composite.We not only identify and extract the gabbro, peridotite, olive gabbro, and diorite, but also effectively distinguish the lithology information between schist and carbonate rock.Because of the wide and strong absorption band of the four kinds of lithology near 1 100 nm in the spectrum caused by Fe2+, we establish the ratio index which is called RI54 to estimate thecontent of Fe2+.

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