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.

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.

In order to quantitatively analyze the time-lag effect between displacement and inducing factors of step-like landslide, as well as to improve the accuracy of displacement prediction, in this study, the authors proposed a new prediction model and conducted comparative analysis. First, the cumulative displacement was separated into trend term and periodic term based on time series analysis. Then, using maximum information coefficient (Cmi) and multivariate empirical mode decomposition (MEMD) for multi-factor analysis and multi-scale analysis, the multi-factor and multi-scale MEMD prediction model was constructed. Finally, taking  Bazimen landslide in  Three Gorges Reservoir area as an example, the optimal lag period inducing factors were selected as the model input through Cmi, and multi-scale prediction model was established based on the decomposition of multivariate sequence by MEMD. The proposed model was compared with other models (single-factor and single-scale model, multi-factor and single-scale model, single-factor and multi-scale EMD model). The results showed that the optimal lag periods of rainfall and reservoir water level in  Bazimen landslide were 2 d and 4 d. After decomposing the landslide multivariate sequence by MEMD, three groups of mode functions were obtained, each group had seven components, and the time-scale of each corresponding component was consistent. The response of the periodic term displacement to the inducing factors had a time multi-scale characteristic. Compared with the comparison model, the root mean square error of the multi-factor and multi-scale MEMD prediction model decreased by 49.4%, 36.9% and 27.4% on average, and the mean absolute percentage error decreased by 38.0%, 26.4% and 15.8% on average.

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.

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.

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.

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.

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.

A geological disaster induced by reservoir impoundment is common. It is important to study the characteristics and stability of deposit slope at reservoir bank before and after impoundment for prevention of such a disaster. Based on the in-situ detailed engineering geological investigation and monitoring materials, the structural and deformation characteristics of deposit slope were analyzed, and the formation and deformation mechanisms were discussed in this study. Finally, based on the discrete element method, the stability of this slope was evaluated. Based on the above research results, the deposit slope was formed from the ancient slide, and the reservoir water level raised by nearly 40m in two months, thus activating the ancient landslides and resulting in the deformation. The engineering treatment such as drainage tunnels and drainage holes slow down the deformation of the slope dramatically, and the deformation of some observation points has a convergence trend.

Based on the comparative analysis of different thermal conduction models of magmatic intrusion, the thermal effect of magmatic intrusion to the organic matter maturity of country rock is simulated, which combined the Easy R_o% model and the reported vitrinite reflectance values (R_o). The numerical simulation results show that the improved Fjeldskaar model can be easy to simulate the thermal maturation of organic matter near the magmatic intrusion and has a good fitting effect. Further more, the alteration of the initial temperature and the thickness of magmatic intrusions have different thermal effects to the organic matter maturity of country rock. It shows that the thermal effect extent is in a limited range. However, this range (X/D, denoted by the ratio of intrusion thickness to the distance which is from the calculation depth to the contact surface) changes with the different geological conditions. Generally speaking, the higher of the initial temperature of the magmatic intrusion is, the broader of the range is, and so does the thickness of magmatic intrusion, but the X/D value is usually less than two (X/D<2). The preliminary application of the thermal conduction model shows that the thermal effect of volcanic process has an important effect to the hydrocarbon generation process, which can accelerate the organic matter maturation of the source rock and advance the hydrocarbon generation period.

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 characteristics of different stages of petroliferous basins are of great significance for the restoration of basin evolution and the evaluation of hydrocarbon generation, storage and transportation conditions. In this study, we systematically reviewed previous studies on the nature and evolution of the Cenozoic western Qaidam basin. Based on the interpretation of seismic profiles combining with the basin tectonic geometry, sedimentation rate, sedimentation phase, sedimentation cycle, sedimentation center migration and unconformity contact relationship within the basin, we concluded that the Cenozoic western Qaidam basin, as a large intracontinental depression in a compressional environment, has an asymmetric geometric configuration in the seismic section, high deposition rate but slightly lower than the western typical foreland basin, and migration of sediment centers due to strong shortening under overcompensation, with obvious reverse cycling sedimentary-tectonic development. Importantly, the deposition of Shizigou Formation is considered as the sedimentary boundary of the Cenozoic western Qaidam basin, showing that in the early stage, fine-grained far-source sediments were developed, belonging to a depression basin; While, in the later period, the sedimentation rate increased significantly, and the coarse-grained deposition developed, which had the characteristics of atypical foreland basin. The fact significantly suggests that it’s controlled by the combination of tectonic activity of the surrounding mountains and overcompensation state of the basin.

Through cyclic triaxial tests for the reinforced soft clay around the tunnel of Baoshan-Hailun station of Shanghai No.4 subway line, the analysis of pore water pressure was made on the reinforced soft clay under subway train loads. The experiments were arranged by orthogonal and repeated design and the factors which had the influence on the pore water pressure were fully considered, including vibration frequency (0.5, 1.5, 2.5 Hz), amplitude of dynamic stress (20, 30, 40 kPa), consolidation ratio (1, 1.4, 2) and over consolidation ratio (1, 1.5, 2). The test data were processed though the fuzzy theory and the fuzzy method to analyze the influence rate of pore water pressure. The result shows the influence rate of pore water pressure on vibration frequency, amplitude of dynamic stress, consolidation ratio and over consolidation ratio is 0.722, 15.821, 0.944 and 6.628 respectively. Main factors which affect the change of pore water pressure are amplitude of dynamic stress and over consolidation ratio. Consolidation ratio and vibration frequency are not significant.

It is difficult to represent the multi-scale structure feature of rocks by using a single resolution digital core model. Through taking a sandstone sample, by means of core multi-resolution CT imaging,the accurate matching of core images with different resolutions is realized by the feature based image registration method. The multi-scale and -component digital core model is constructed along with the segmentation of pores and minerals in the registered images based on image fusion. The results show that the multi-scale and -component digital core model could represent the cross scale pore structures; and the pore distribution agrees with the results from NMR. The mineral contents of digital core are more consistent with the results from XRD than that from Qemscan. The multi-scale and -component digital core model factually restores the structure features of all rock components.

The optimum proportion of cement clinker was determined by orthogonal test, displaying as the lime saturated coefficient was 0.92, the silicon rate was 2.5, the aluminum rate was 1.5; the best calcining temperature of cement clinker was 1 350 ℃. According to the above experiment conditions, cement clinker was prepared using industrial material as raw material. The XRD results show that mineral composition of the asprepared cement clinker is similar to the cement clinker in Yatai cement plant of Jilin Province. Oil shale, as the mixing material, is added to cement clinker directly. The relevant experimental results show that with the increasing adding quantity of oil ash, strength decreases significantly in 3 days; but later reinforcing effect is higher. The intensity of 28 days is relatively stable. If cement intensity meets the PC32.5 standards, the maxmium adding quantity of oil ash should be 35% to 40%.

The traditional technology of exploration and recognition oil shale mainly rely on geological survey on the field, core and sample testing and analyzing. On the basis of analysis and research on geological survey on the field, the description of core, log and test data analysis, and comprehensive research, the paper proposed a qualificative and quantitative technology of recognizing oil shale effectively using well-logging data, and applied them in the Songliao basin. Properties of oil shale is high resistivity, high gamma, high sonic and low density in the well longing data. Resistivity data is the best about the correlation between oil yield of oil shale and well logging parameters. The one member linear regression relationship between oil yield of oil shale and the well logging data is better than that of two members and three members. Not only oil yield but also total organic carbon can be calculated using ΔlgR technology. The calculated results show that the deviation between calculated oil yield and testing oil yield is relatively small using the linear relationship between oil yield of oil shale and the resistivity well-logging data and ΔlgR technology.

Geomagnetically induced currents (GIC) are currents induced in conductive materials on the Earth’s surface due to Earth’s magnetic field variations. GICs have the potential to cause severe damage to manufactured infrastructure, including power grids, oil and gas pipelines, and high-speed railways, resulting in adverse consequences such as power system failures, communication disruptions, and damage to electronic equipment, ultimately affecting the stability and functionality of these systems. The significance of studying GIC lies in understanding their generation mechanisms and influencing factors, thereby providing a scientific foundation for developing effective prevention and mitigation strategies. Based on an in-depth review of the progress in GIC research, this paper elaborates on the mechanisms of GIC generation and the influencing factors, encompassing the impacts of space weather, Earth’s environmental conditions, and the power system on GIC. It provides an overview of the current state of GIC research, offering integrated assessments from space physics, geophysics, and electrical engineering. Furthermore, the paper provides a detailed description of the steps involved in estimating GIC, including using geomagnetic field data and modeling, along with calculating electric fields and GIC within conductors. It emphasizes analyzing how various geophysical parameters affect GIC estimates and their interrelationships. In conclusion, the paper discusses the challenges in GIC research, highlights the potential contributions of geophysics in addressing related issues, and provides a perspective on the future of GIC research.

Yishu fracture zone is the Shandong section of Tanlu fracture zone. The fracture is not only large in scale, but also strongly active, which has the tectonic framework of "two grabens with one base". Based on the 1:200 000 seabed high-precision gravity survey data, the characteristics of gravity field in Laizhou Bay of Yishu fault zone were studied. The data were processed and interpreted by Euler deconvolution and texture analysis for equal boundary recognition in order to refine the tectonic framework of the study area. According to the characteristics of gravity field, 22 faults are inferred, and the main faults are NE-NNE and near EW faults. The four main faults of Yishu fault zone are distributed in Laizhou Bay, in NNE-trending, paralleling, soothing and undulated. The tectonic units are initially divided into three third level, five forth level,and twelve fifth level of tectonic units. It is inferred that on the west side of the Changyi-Dadian fault the high gravity reflects the basal uplift, and the low gravity mainly reflects the Mesozoic-Cenozoic depression; while on the east side of the fault the high gravity mainly reflects the distribution of the Early Precambrian metamorphic rocks, and the low gravity mainly reflects the distribution of the Mesozoic sequence rocks.

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.

Along with the rapid development of marine economy, ever increasing emphasis has been put on strengthening marine defense security, improving the development of marine resources and protecting the marine ecological environment, the three aspects which complement to each other; and the corresponding effective detection technology, the key to ensure the marine safety and security, the resource development efficiency, and the balance of ecology and real-time monitoring, as well as to prevent pollution, has become a hot research focus in the current ocean related research and engineering field. Based on the unique advantages of optical fiber sensor over traditional electronic and mechanical sensors, this paper gave an introduction to the technology, system design and characteristics of fiber sensing, in the fields including coastal defense and livelihood security, subsea natural disaster prediction, effective exploration of ocean energy, ocean engineering safety monitoring, and marine environment online monitoring.Consquently, the present review aims to promot optical fiber sensing technology in the ocean.

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.

 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.

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.

The vibration of drillstring is a common problem while drilling. Serious vibration is one of the most important reasons leading to bit and drillstring failure, which can reduce drilling efficiency and increase cost. So how to identify and suppress drilling vibration is a vital task and many researches have been done about this. Through the review of theoretical study and latest progress of drillstring dynamics, summarization of laboratory test research, the latest development of vibration monitoring device and suppression tool are introduced in this paper. Main solution of the problem should include drillstring dynamics software on the basis of theoretical study and laboratory test, vibration monitoring device and proper vibration suppression tool. Meanwhile, the research of vibration suppression integrated technology is proposed.

The situation of geo-hazards is severe in China. The status, trend and problem of geo-hazards prevention are discussed in this paper. On the one hand, in the view of geo-hazards prevention, the basis status of geo-hazards in China is discussed, and the prevention system of geo-hazards in China is studied. Then, with a typical debris flow, occurring in August 8， 2010， in Zhouqu County, Gansu Province， in the southwestern  China, some problem and deficiency of geo-hazards prevention are discussed. On the other hand, in the view of geo-environment development, evaluation frame and system of regional geo-environment sustainable development are constructed, and geo-environment safety management is advanced. Finally, conclusions are as following: we should escape from the habitual thought of the single engineering geological evaluation or the single geo-hazards prevention. The protection of geo-environment and prevention of geo-hazards should be organic integrated to ease geo-hazards.

Target detection is a fundamental and routine task in remote sensing image processing. In this paper, we design a target detection algorithm for remote sensing images based on the YOLOX network. Firstly, ASFF is added to the feature extraction module PANet to deeply mine the fine features with inconsistent scale in target detection. Secondly, an ECA-based feature extraction module is designed with efficient channel interaction to reduce the complexity of the model while paying more attention to the positive sample feature information in the feature map. Then, to avoid the problem of gradient disappearance and weak activation effect caused by overfitting, the use of swish activation function is proposed. Finally, experiments are conducted on DOTA to verify the best mechanism and effectiveness of the improved method through qualitative analyses of the ablation experiments and quantitative comparison experiments. With the addition of ASFF and ECA mechanisms and the optimization of the swish activation function, the improved network model achieves an mAP of 74.42%, an improvement of 12.75% over the original network. Compared with the current widely used target detection algorithms Mobilenet-YOLOv4, YOLOv4, YOLOv5 and YOLOX, the proposed  algorithm achieves an improvement of 11.42%-17.84% in mAP accuracy.

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.

Deep exploration instrumentation and technologies provide technology supporting for national crust probing plan that discovery deep earth profound, which development level will  decide capability of acquisition and interpretation of data and information from huge continental and marine areas and ultra deep in China. In light of national high technique strategy with aiming at international high-ranked technology, development by the country has to be carried out to meet the request of probing capability and efficiency in geological complexity environment. The development has been designed in several phases and six technique directions, in order to speed up the level of the development. With strengthening cooperation of development units, R&D basis is established with introducing experts,  professional training, importing and learning high-end products and techniques. In this way, it is possible to refined innovation and university manufactory-academic-utilization role and to fast change embarrassing situation of a long term relying on importing all of instruments and technologies. It is hopefully benefit to a huge span pace from the beginning to qualification.

Located in Qimantage area of southwest Qaidam basin,Kaerqueka copper polymetallic deposit is a characteristic hydrothermal vein-skarn ore deposit controlled by the fractured and altered zone. Two kinds of wall-rock alterations can be recognized in the ore deposit, i.e., skarn and phyllic alteration. The former was formed by intrusion of Indosinian porphyaceous biotite adamellite. Copper polymetallic skarn lenticular bodies are commonly seen in the contact zone of the intrusion, different lithologic interfaces and faulted structural zones of the surrounding rocks. There are some typical calcium skarn minerals, such as diopside, hedenbergite, andradite, hessonite, idocrase, wollastonite, epidote, scapolite and actinolite. The latter forms many parallel NWW-striking chacopyritized hydrothermal alteration zones in porphyaceous biotite adamellite in the northwest part of the ore district, belonging to hydrothermal vein type mineralization controlled by faulted fractured zones. It is concluded that Kaerqueka copper polymetallic deposit is related to Indosinian hypabyssal and high emplacement porphyaceous biotite adamellite. The ages of rocks and ores in the copper polymetallic skarn deposit and the veinlet-disseminated hydrothermal veinlike copper deposit are the same, and the backgrounds of tectono-magmatic activities are identical; nevertheless, they are products of different ore-forming processes that occurred at different stages, different depths and different parts. This ore deposit is a compound one, with the skarn copper polymetallic mineralization as the main body, accompanied by the hydrothermal vein type copper mineralization in well-developed faults of the parent rock.

The Baiyun gold deposit is one of large gold deposits in eastern Liaoning Province,with many controversies on ore-forming material source and ore genesis. This paper presents systemic researches on stable isotope geochemistry of H, O, S and C in this deposit. The δ¹⁸O_V-SMOW and δD_V-SMOW values of the ore-forming fluid range from 13.5‰ to 15.9‰ and from -107‰ to -83‰, respectively, which indicates that the ore-forming fluid is mainly composed of magmatic fluids. δ³⁴S_V-CDT values of pyrite grains in the ores range from -8.3‰ to 2.9‰, with enrichment of ³²S and depletion of ³⁴S, and have great difference from the sulfur isotope composition of surrounding rocks(7.0‰~18.7‰). δ¹³C_V-PDB values of the calcite in the ores range from -2.2‰ to -0.4‰, suggesting its igneous carbonates or mantle xenoliths source and obviously different from the composition of carbon isotope of marble of Liaohe Group. The comparison of ore-forming elements in the different geological bodies shows that the source of ore-forming material has no necessary correlation with strata of the Liaohe Group. The geologic and geochemical features of the Baiyun deposit suggest that this gold deposit belongs to the magmatic hydrothermal gold deposit related to hypomagmaism.

In order to comprehensively characterize the pore structure and storage-seepage capability of multi-type reservoirs in fracture-cavity carbonate gas reservoirs, a series of test techniques were used to study the samples from the Deng 4 Member in Gaoshiti-Moxi block of Sichuan basin. At first, the lithology, physical property, storage space and throat of the reservoirs were qualitatively described by thin section and scanning electron microscope. Then, the reservoirs were classified according to the capillary pressure curves obtained by high pressure mercury injection. Finally, the two and three dimensional pore structure characteristics of three types of samples were quantitatively determined based on multi-scale CT scans. The study results show that:The storage space is composed of intergranular dissolved pores, intra-granular dissolved pores, inter-crystalline dissolved pores, solution cavities, solution fractures, and structural fractures; the throat type mainly contains necking throat, punctual throat, and control shape throat; the reservoirs can be classified to fracture-cavity type, cavity type, and pore type; in fracture-cavity-type reservoirs, large pores and cavities are developed, uniformly distributed, and connected well,and coarse throats are numerous, micro-fractures and dissolution cavities are beaded in series, which are connected with the isolated storage space and has the best storage and seepage capability; in cavity-type reservoirs multi-scale pores and cavities are developed with strong storage capability, throats are coarse but few and poorly connected with limited seepage capability; in pore-type reservoirs, small pores are developed and unevenly distributed, and most of the spaces are occupied by rock skeleton with few throats and poor connectivity, leading to weak storage-seepage capability.

In this paper, the authors review the history of grain size analysis, summarize the commonly used grain size types, introduce the grain size standards and the five grain size analysis methods usually used in sedimentology at present, and give a detailed classification of sedimentation method, field interference analysis method and image method. In addition, the scope of application, the principle of measurement, the advantages and disadvantages of each grain size analysis method are also introduced in detail. Of them,direct measurement method is simple, but poor in accuracy; Sieving analysis is common, but can only precede loose or weakly cemented sediments and cannot reflect grain shape; Sedimentation method is suitable for the analysis of loose samples, weak cemented samples and liquid samples, and can measure fine grained sediments such as fine sand, silt and mud; Field interference method is mainly based on the diffraction, scattering and voltage impulse response of detritus grains, both solid and liquid samples, with high accuracy, and wide applicability; Image method is diverse, simple and intuitive, and strongly operable. In general, in the next few decades, these grain size analysis methods will still co-exist with old and new technologies.

Qinghai-Tibet Plateau permafrost region is the largest region in low latitude regions in the world. Climate warming could leads mean annual ground temperature to rise, the ground ice to melt and permafrost to degrade, and so on. By supporting of ARCGIS software the changes of ground ice content and active layer thickness are calculated by using ground ice model and Stefan equation under different climate change scenarios. The results show that: the distribution of permafrost will not have a significant change in the next few decades but a large-scale changes will take place at the end of this century.The main permafrost degradation types are the melting of ground ice and converted the low-temperature to high-temperature permafrost. The large-scale changes will accompany with the thermal hazards such as thermokarst and thermal slump. Thermal hazards are zoned on the Qinghai-Tibet Plateau permafrost region according to the modified Nelson model. The greatest danger zone distributed in the south of the West Kunlun Mountains mainly, Middle of Qingnan Valley, and southern foot of Gangdise Mountains, Nyainqentanglha Mountains, and the Himalayas Mountains. Thermal hazards will be exacerbated in future several decades.