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.

 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.

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.

 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.

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.

 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.

 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.

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.

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.

 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.

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.

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.

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.

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.

 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. 

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.

 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. 

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.

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

 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%.

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.

 Volcanic facies is the sum of volcanic material eruption type, transport mode, emplacement environment and state. The classification of volcanic facies is the basis for characterizing the distribution of volcanic rocks in a basin and searching for favorable volcanic reservoirs, which plays an important role in the exploration of volcanic oil and gas in a basin. Based on the “lithology, petrofabric and petrogenesis” of volcanic rocks, a classification scheme of “5 facies and 15 subfacies” of volcanic rocks in the basin was established, which greatly promoted the exploration process of deep volcanic rocks in China basins. At present, the largescale volcanic oil and gas exploration in basins in China has gone through a course of more than 20 years, and with the indepth exploration, the lithofacies classification scheme has been improved and enriched: For the intermediatemafic volcanic lava, the intermediatemafic effusive lava flow facies has been established, and three subfacies have been divided into braided lava flow unit, tabular lava flow unit and the lava dome. Aiming at subaqueous volcanic eruption in lacustrine basin, three subfacies and facies models of subaqueous volcanic eruption phase, gassupported hot pyroclastic flow subfacies, waterlaid density current subfacies and subaqueous fallout subfacies are established. A new classification scheme of “7 facies and 21 subfacies” was formed. In the intermediatemafic volcanic lava facies, the braided lava flow subfacies has the best development conditions, followed by the hyaloclastic rock subfacies and the tabular lava flow subfacies. Gassupported hot pyroclastic flow subfacies control the spatial distribution of effective reservoirs in the subaqueous volcanic eruption facies. The establishment of the intermediatemafic effusive lava flow facies overcomes the difficulty in characterizing the subfacies of the basic lava due to the thin monolayer thickness and the difficulty in drilling and seismic characterization. The establishment of subaqueous volcanic explosive facies has realized the accurate characterization of volcanic facies in different eruptive environments of sedimentary basins from land to subaqua. The establishment of the two lithofacies provides a basis for further exploration of the reservoir development law in the intermediatemafic effusive development area and the subaqueous volcanic eruption pyroclastic rock development area and searching for favorable reservoirs.

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.

 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.

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.

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.

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.

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.

 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. 

 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.

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.

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.

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.

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.

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.

 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.

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.

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.

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.