Injection-Production Process Parameters Of Well Group Configurations For Autothermic Pyrolysis In Situ Conversion Of Oil Shale,
2025
State Key Laboratory of Deep Earth Exploration and Imaging, College of Construction Engineering, Jilin University, Changchun 130026, China; National-Local Joint Engineering Laboratory of In-situ Conversion, Drilling and Exploitation Technology for Oil Shale, Changchun 130026, China; Provincial and Ministerial Co-construction of Collaborative Innovation Center for Shale Oil & Gas Exploration and Development, Changchun 130026, China; Key Lab of Ministry of Natural Resources for Drilling and Exploitation Technology in Complex Conditions, Changchun 130026, China
Injection-Production Process Parameters Of Well Group Configurations For Autothermic Pyrolysis In Situ Conversion Of Oil Shale, Zeng Yijian, Zhu Chaofan, Li Yanwei, Shui Haoche, Guo Wei
Coal Geology & Exploration
Background A well group acts as a multi-well synergistic unit, and its configuration directly determines both the selection of optimal injection–production process and the utilization efficiency of stratigraphic conditions, ultimately affecting the overall performance of resource recovery. Methods Using numerical simulations, this study assessed the performance of autothermic pyrolysis in situ conversion (ATS) under three vertical well group configurations: one injection well and one production well (1I1P), one injection well surrounded by four production wells (1I4P), and one injection well surrounded by six production wells (1I6P). Furthermore, it revealed the synergistic mechanisms between well group configuration and energy efficiency. Results …
High-Precision Reconstruction Of Seismic Data Based On Improved U-Net++,
2025
School of Geosciences, Guilin University of Technology, Guilin 541004, China
High-Precision Reconstruction Of Seismic Data Based On Improved U-Net++, Wang Minling, Zhou Fei, Wang Honghua, He Xiang, Hou Zhiyang
Coal Geology & Exploration
Objective Conventional reconstruction methods are insufficient for the reconstruction of seismic data with missing consecutive traces, producing a negative impact on subsequent processing accuracy. Hence, this study proposed CU-Net++, a deep learning network based on the U-Net++ architecture combined with the convolutional block attention module (CBAM). Methods During the reconstruction of missing data, the independent decoder for each sub-U-Net in the nested U-Net++ architecture enables the utilization of information from different depths. The long and short skip connections can effectively enhance the network's capability to extract multi-scale features from data. The core innovation of CU-Net++ is the introduction of CBAM, …
Attenuation Characteristics And Wave Impedance Inversion Of Depth-Domain Nonstationary Seismic Data,
2025
Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Xiamen 361000, China; Technology Innovation Center for Geothermal & Hot Dry Rock Exploration and Development, Ministry of Natural Resources, Shijiazhuang 050061, China
Attenuation Characteristics And Wave Impedance Inversion Of Depth-Domain Nonstationary Seismic Data, Ma Ming, Ma Feng
Coal Geology & Exploration
Background The efficient application of depth migration methods has enabled the extensive implementation of depth-domain seismic data interpretation. Previous studies on the impacts of time-to-depth conversion and velocity models merely determine that an increase in depth corresponds to reduced dominant wavenumber of seismic waves and waveform stretching, without considering the changes in amplitude and phase. Objective This study aims to accurately characterize the waveforms of nonstationary seismic signals in the depth domain and enhance the impedance inversion accuracy. Methods First, based on energy dissipation and frequency dispersion effects during the propagation of seismic waves, this study investigated the complex mapping …
Application Of Geophysical Logging To Selection Of Optimum Target Horizons For Salt Cavern Storage: A Case Study Of Borehole Zk01 In Qingjiang Salt Mine, Jiangxi Province, China,
2025
State Key Laboratory of Deep Earth Exploration and Imaging, Institute of Geophysical and Geochemical Exploration, Chinese Academy of Geological Sciences, Tianjin 300300, China; Laboratory of Geophysical EM Probing Technologies, Ministry of Natural Resources, Tianjin 300300, China; State Research Center of Modern Geological Exploration Engineering Technology, Tianjin 300300, China
Application Of Geophysical Logging To Selection Of Optimum Target Horizons For Salt Cavern Storage: A Case Study Of Borehole Zk01 In Qingjiang Salt Mine, Jiangxi Province, China, Liu Dongming, Lin Zhenzhou, Liu Dongyan, Qiu Changyi, Liang Mingxing, Zhai Jinghong, Zhang Jie, Jiang Zhengzhong
Coal Geology & Exploration
Background Under the guidance of the strategies to achieve the goals of peak carbon dioxide emissions and carbon neutrality, salt cavern storage facilities, serving as key infrastructure for clean energy strategic reserves, have emerged as a core approach to promoting the transformation and upgrade of the salt industry and to building a low-carbon energy system in China. Jiangxi Province, located in the middle part of the Yangtze River Economic Belt, is endowed with abundant salt rock resources, making it a national priority zone for developing resources for salt cavern storage. However, traditional methods for the siting of the facilities rely …
Analysis Of The Connotation Of Hidden Disaster-Causing Factors In Coal Mines And The Key Points Of Their Reconnaissance,
2025
Hebei Key Laboratory of Mine Disaster Prevention and Control, North China Institute of Science and Technology, Beijing 101601, China; Hebei Technology Innovation Center for Intelligent Emergency Response to Multi-Scenario Water Disaster Chain Accidents, North China Institute of Science and Technology, Beijing 101601, China
Analysis Of The Connotation Of Hidden Disaster-Causing Factors In Coal Mines And The Key Points Of Their Reconnaissance, Lian Huiqing, Wang Xu, Yin Shangxian, Xia Xiangxue, Cao Min, Li Qixing, Wu Xiaoming, Zhang Bin, Wang Yangyu, Zhang Qing, Wang Guo’An
Coal Geology & Exploration
Background To systematically normalize the reconnaissance of hidden disaster-causing factors in coal mines, the National Mine Safety Administration issued the Specification for General Survey of Hidden Disaster-causing Factors in Mine in 2024. Nevertheless, coal mining enterprises still face a range of notable issues in reconnaissance of hidden disaster-causing factors, including ambiguous connotations of the factors, broad scopes of reconnaissance, unclear implementation stages, a disjunction between explorations and reconnaissance, and improper conclusion descriptions. These problems severely restrict scientific and operational reconnaissance.Methods This study reviews the history of research on the reconnaissance of hidden disaster-causing factors, presents a summary of significant …
Molecular Simulations Of Selective Adsorption Of Lithium In The No.6 Coal Seam, Junggar Coalfield,
2025
College of Geological and Surveying Engineering, Taiyuan University of Technology, Taiyuan 030024, China
Molecular Simulations Of Selective Adsorption Of Lithium In The No.6 Coal Seam, Junggar Coalfield, Zhang Junshuang, Sun Beilei, Zhang Bin, Liu Chao
Coal Geology & Exploration
Objective With the discovery of metal deposits in coal-bearing strata, the distribution and occurrence patterns of lithium in coals have attracted much attention. However, its partitioning mode between organic structures and minerals in coals remains poorly understood.Methods This study investigated typical coals with a high lithium content in the Junggar Coalfield in Inner Mongolia. By integrating multiple simulation methods, including quantum mechanics, Monte Carlo simulation, and molecular dynamics, this study established the structural models of organic matter and inorganic minerals, as well as a visualized lithium-coal molecular structure model. Accordingly, it investigated the preferential adsorption sites on both organic …
Molecular Simulation Of Adsorption And Diffusion Behaviors Of High-Concentration Helium In Salt Cavern Storage Reservoirs,
2025
National Energy Underground Gas Storage Research and Development Center, Langfang 065007, China; PetroChina Research Institute of Petroleum Exploration & Development, Beijing 100083, China
Molecular Simulation Of Adsorption And Diffusion Behaviors Of High-Concentration Helium In Salt Cavern Storage Reservoirs, Chen Zeya, Wanyan Qiqi, Liu Mancang, Liu Xiaoqiang, Chen Jianfa, Li Kang, Wu Jianan, You Bing
Coal Geology & Exploration
Background Artificial salt cavern underground helium storage is the optimal approach for achieving long-term, large-scale strategic helium storage and represents an essential solution for establishing an autonomous, controllable helium supply system. The core challenge currently constraining China’s development of salt cavern underground helium storage facilities lies in the sealing capacity of salt rock against high-concentration helium (helium volume fraction ≥70%). Methods Molecular dynamics simulation was used in this study, a composite model of salt rock slit pore and channel pore was constructed to reveal the influences of temperature-pressure conditions, helium concentration, and pore fluid properties on the occurrence state and …
Source And Primary Factors Controlling Differential Enrichment For Helium In The Dongping Gas Field, Qaidam Basin,
2025
Research Institute of Science and Technology, CNPC, Beijing 100083, China; Research Institute of Petroleum Exploration and Development, CNPC, Beijing 100083, China; Key Laboratory of Gas Reservoir Formation and Development, CNPC, Langfang 065007, China
Source And Primary Factors Controlling Differential Enrichment For Helium In The Dongping Gas Field, Qaidam Basin, Xu Zhusong, Li Jian, Wang Xiaobo, Cui Huiying, Xia Yutian, Tian Jixian, Li Wanting, Chen Dawei
Coal Geology & Exploration
Background In recent years, promising helium-rich natural gas shows have been discovered in the Dongping gas field. However, the helium resources in the gas field exhibit lateral heterogeneity and vertical differential accumulation in multiple sequences, which restrict the further exploration of these resources. Methods By analyzing the lateral and vertical distribution characteristics of helium in the Dongping gas field, this study explored its origin and sources, analyzed the differences in geological backgrounds between helium-rich and helium-deficient gas reservoirs, and systematically summarized the differential enrichment pattern across different blocks within the Dongping gas field.Results and Conclusions In the Dongping gas …
Water Filling Intensity Assessment Of A Coal Seam Roof In The Dahaize Coal Mine, Northern Ordos Basin,
2025
China Coal Energy Research Institute Co., Ltd., Xi’an 710054, China
Water Filling Intensity Assessment Of A Coal Seam Roof In The Dahaize Coal Mine, Northern Ordos Basin, Liu Xi, Ding Xiang, Huang Haiyu, Li Zhaoyang, Li Zhe, Zheng Sheng
Coal Geology & Exploration
Background Assessing water filling intensity in coal seam floors lays a foundation for the prevention and control of water hazards in mines. However, in the Jurassic coalfield in the northern Ordos Basin, complex hydrogeological structures and sedimentary heterogeneity pose severe challenges to traditional evaluation methods. Methods This study investigated the water hazard characteristics in the superimposed aquifers of the Jurassic Yan’an and Zhiluo formations in the Dahaize Coal Mine in northern Shaanxi. The purpose is to establish a zoning and assessment system of water filling intensity that is suitable for continental sedimentary settings and to provide a scientific basis for …
Characteristics And Formation Processes Of Helium-Bearing Gas Reservoirs In Deep Strata In The Xujiaweizi Fault Depression, Songliao Basin,
2025
School of Earth and Space Sciences, Peking University, Beijing 100871, China
Characteristics And Formation Processes Of Helium-Bearing Gas Reservoirs In Deep Strata In The Xujiaweizi Fault Depression, Songliao Basin, Ren Jiahao, He Yanxin, Tian Wei, Wang Lei
Coal Geology & Exploration
Objective and Method The Xujiaweizi Fault Depression in the Songliao Basin contains multiple helium-bearing gas fields. However, the assessment methods for helium resources and helium accumulation patterns in the fault depression are yet to be determined. Using 3D seismic data and logs from 24 wells, this study optimized the helium resource assessment method based on natural gamma-ray spectral logging. Using the optimized method, this study quantitatively assessed the helium-generating potential and theoretical helium production of crust-derived helium in deep strata in the Xujiaweizi Fault Depression. By combining the geochemical characteristics of the helium-bearing gas reservoirs and the simulation results of …
Diagnosis, Prevention, And Control Of Liquid Accumulation In Horizontal Wellbores For Deep Coalbed Methane: A Case Study Of The Daning-Jixian Block Along The Eastern Margin Of The Ordos Basin,
2025
College of Petroleum Engineering, China University of Petroleum (Beijing), Beijing 102299, China; National Engineering Research Center of China United Coalbed Methane Co., Ltd., Beijing 100095, China
Diagnosis, Prevention, And Control Of Liquid Accumulation In Horizontal Wellbores For Deep Coalbed Methane: A Case Study Of The Daning-Jixian Block Along The Eastern Margin Of The Ordos Basin, Zeng Wenting, Wang Zhiming, Zhang Lei, Tian Zhida, Zhen Huaibin, Dai Anna, Zeng Quanshu, Sui Tianyang
Coal Geology & Exploration
Objective The Daning-Jixian block on the eastern margin of the Ordos Basin has achieved large-scale production of deep coalbed methane (CBM), with nearly 150 horizontal wells having been put into production. However, with a gradual decrease in formation energy during CBM production, gas wells exhibit declining liquid-carrying capacity. Consequently, liquid accumulation in wellbores has become a major factor affecting deep CBM production. Recovery of deep CBM shows the coexistence of free and desorbed gases, accompanied by significantly varying gas/liquid ratios. Moreover, gas production channels and techniques vary in different production stages. Hence, there is an urgent need to develop a …
A New Genesis Method-Based Methodology For Helium Resource Evaluation: Application To The Jinzhong Basin And Its Geological Implications,
2025
Xi’an Center, China Geology Survey, Geosciences Innovation Center of Northwest China, Xi’an 710119, China; Research Center for Helium, China Geology Survey, Xi’an 710119 China
A New Genesis Method-Based Methodology For Helium Resource Evaluation: Application To The Jinzhong Basin And Its Geological Implications, Zhang Qiao, Zhou Junlin, Ma Shangwei, Guo Wang, Li Yuhong, Zhang Yunpeng, Zhang Yuxuan, Xu Haihong, Wang Jiawei
Coal Geology & Exploration
Background Helium, a strategic resource in short supply, primarily occurs in natural gas. In China, helium resource assessment remains in its nascent stage, and limited helium exploration and exploitation have been conducted in general. Most especially, for regions experiencing no natural gas exploration and basins where helium reserves remain unproven, it is essential to develop reliable methods for helium resource evaluation. Among various approaches, genesis methods, based on models of helium generation, migration, and enrichment processes, offer advantages including simple models, accessible parameters, and rapid assessment. However, existing genesis methods focus primarily on the estimation of the total amount of …
Sedimentary Environments And Microscopic Water Control Patterns In The Luohe Formation, Gaojiapu Coal Mine, Binchang Mining Area,
2025
1CCTEG Xi’an Research Institute (Group) Co. Ltd., Xi’an 710077, China; Shaanxi Provincial Geological Survey Institute, Xi’an 710004, China; College of Geology and Environment, Xi’an University of Science and Technology, Xi’an 710054, China; Water Disaster Control Branch Laboratory, National Key Laboratory of Coal Mine Disaster Prevention and Control, Xi’an 710077, China
Sedimentary Environments And Microscopic Water Control Patterns In The Luohe Formation, Gaojiapu Coal Mine, Binchang Mining Area, Li Xiaolong
Coal Geology & Exploration
Objective and Method The exploration of the Luohe Formation, located on the roof of the Huanglong Jurassic coalfield, faces challenges such as a lack of consensus on the sedimentary environments of sandstone aquifers and unclear lithologies with water yield properties in the aquifers. To address these challenges, this study investigated sandstones in the Luohe Formation in the Gaojiapu Coal Mine, Shaanxi Province. Specifically, a comprehensive analysis of core samples with different lithologies was conducted, including colors, lithologies, lithologic assemblages, the surface morphology of quartz grains, mineral components, and sedimentary structures and textures. Based on analytical results, as well as the …
Geothermal Resource Assessment Of The Eastern Da’An Area Based On 3d Geothermal Geological Modeling,
2025
School of Geosciences, Yangtze University, Wuhan 430100, China; Hubei Key Laboratory of Complex Shale Oil and Gas Geology and Development in Southern China, Yangtze University, Wuhan 430100, China
Geothermal Resource Assessment Of The Eastern Da’An Area Based On 3d Geothermal Geological Modeling, Chen Wenwen, Rao Song, Meng Boyan, Guo Menghao, Luo Yang, Cai Jiahao, Li Wenjing, Zhang Qiaoran, Tang Yucong
Coal Geology & Exploration
Objective The Da’an area in Jilin Province, located in the southwestern Central Depression of the Songliao Basin, exhibits significant geothermal anomalies, which suggest substantial potential for geothermal exploitation. However, there remains a lack of detailed geothermal resource assessment of this area. Among conventional assessment methodologies, the volumetric method fails to accurately characterize irregular stratigraphic geometries and the spatial heterogeneity of parameters, while the Monte Carlo method suffers from limitations such as heavy dependence on the probability distribution models of geothermal reservoir parameters. Methods To overcome the limitations of the conventional methods, this study established a 3D geothermal geological model by …
A Collocation Point Sampling Method For Solving The Helmholtz Equation Using Physics-Informed Neural Networks,
2025
Key Laboratory of Deep Petroleum Intelligent Exploration and Development, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China; College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
A Collocation Point Sampling Method For Solving The Helmholtz Equation Using Physics-Informed Neural Networks, Shan Lianpu, Yu Caixia, Wang Yanfei
Coal Geology & Exploration
Background In the field of seismic wavefield simulation, physics-informed neural networks (PINNs) have emerged as a new method for efficiently solving the Helmholtz equation due to their characteristic of grid-free computation. However, for the forward modeling of complex medium models using the Helmholtz equation, traditional uniform grid-based methods for collocation point sampling are insufficient to efficiently provide gradient information, leading to prolonged training time and high resource consumption. Objective and Method To improve the forward modeling efficiency and accuracy based on PINNs and overcome the anomalous concentration of collocation points in the seismic source during dynamic sampling, this study proposed …
Anomalous Responses Of Coal Seam Mining Face Floor Derived Based On Stress-Induced Failure Modeling And 3d Direct Current Electric Method,
2025
College of Energy and Mining Engineering, Shandong University of Science and Technology, Qingdao 266590, China
Anomalous Responses Of Coal Seam Mining Face Floor Derived Based On Stress-Induced Failure Modeling And 3d Direct Current Electric Method, Gao Weifu, Zou Xu, Niu Chao, Xiao Lele, Zi Jianxiao
Coal Geology & Exploration
Objective In recent years, floor water inrushes have frequently occurred in North China-type coalfields. To address this challenge, determining the anomalous responses of water inrushes from stope floors has emerged as a focus of research on water disaster prevention and control. Methods This study established a stress model of the stope floor based on the mine pressure theory. Using this model, it analyzed the stress distribution and failure characteristics of the stope floor. The floor failure characteristics revealed that the coal seam floor can be divided into three zones: the compression, expansion, and recovery zones. Through stress-resistivity tests, this study …
Technologies And Equipment For Efficient Drilling Rescue,
2025
CCTEG Xi’an Research Institute (Group) Co., Ltd., Xi’an 710077, China
Technologies And Equipment For Efficient Drilling Rescue, Yao Ningping, Zou Zujie, Zhang Zhonghai, Zhao Jiyun, Hao Shijun, Fan Dong, Dou Bin
Coal Geology & Exploration
Objective In China, mining operations are progressively extending to greater depths, with annual tunneling of mine roadways and tunnels nationwide reaching nearly 20000 km. In this context, mine (tunnel) accidents occur frequently, threatening the safety of state property and people’s lives. To meet the great demand for emergency rescue in mine (tunnel) accidents, drilling rescue, emerging as a hot topic, has been employed as an effective approach. Methods Techniques and equipment for efficient and safe drilling of surface and underground (tunnel) rescue boreholes were investigated by centering on two main roadmaps: (1) surface rescue equipment – forming techniques for search …
Spatiotemporal Evolution Pattern Of The Inertial Horizontal Displacement Of Mining Overburden And A Surface Prediction Model Considering Inertial Horizontal Displacement,
2025
School of Earth and Environment, Anhui University of Science & Technology, Huainan 232001, China; State Key Laboratory for Safe Mining of Deep Coal Resources and Environment Protection, Anhui University of Science & Technology, Huainan 232001, China; Engineering Research Center of Mining Area Environmental and Disaster Cooperative Monitoring, Anhui University of Science & Technology, Huainan 232001, China; Key Laboratory of Aviation-aerospace-ground Cooperative Monitoring and Early Warning of Coal Mining-induced Disasters of Anhui Higher Education Institutes, Anhui University of Science & Technology, Huainan 232001, China; School of Geography and Planning, Chizhou University, Chizhou 247000, China
Spatiotemporal Evolution Pattern Of The Inertial Horizontal Displacement Of Mining Overburden And A Surface Prediction Model Considering Inertial Horizontal Displacement, Chen Yuanfei, Wang Lei
Coal Geology & Exploration
Objective Substantial measured data indicate that the along-strike horizontal displacement of the surface tends to be nonzero in the central part of the mining-affected zone. This phenomenon deviates from traditional understanding, leading to systematic deviations in the predicted results of the traditional prediction model for horizontal displacement. Methods This study investigated mining face 1414 of the Guqiao Coal Mine in the Huainan mining area, Anhui Province. Using measured data and numerical simulation methods, this study explored the spatiotemporal evolution of the horizontal displacement within the mining overburden and of the surface. Then, it analyzed the sources, patterns, and distribution characteristics …
Spatial Distribution Of Coalbed Methane Migration Pathways And Selection Of Optimal Target Areas For Coalbed Methane Extraction For Abandoned Mines,
2025
School of Mining Engineering, Anhui University of Science and Technology, Huainan 232001, China; Anhui Engineering Research Center of Exploitation and Utilization of Closed/Abandoned Mine Resources, Huainan 232001, China
Spatial Distribution Of Coalbed Methane Migration Pathways And Selection Of Optimal Target Areas For Coalbed Methane Extraction For Abandoned Mines, Liu Qinjie, Yang Youxing, Wu Benniu, Duan Minke, Deng Zhuoyue, Guo Chenye, Sun Qiang
Coal Geology & Exploration
Objective and Methods The spatial distribution and long-term evolution of effective migration pathways determine the migration pathways of residual coalbed methane (CBM) in abandoned mines. Furthermore, they provide an important basis for selecting the optimal target areas for CBM extraction drilling in abandoned mines and maximizing extraction efficiency. This study investigated the first mining area at the first horizontal elevation of the Songzao Coal Mine in Chongqing. Using a comprehensive approach that integrated theoretical analysis, numerical simulations, and physical simulation experiments using similar materials, this study systematically examined the distribution patterns of effective CBM migration pathways in abandoned mines under …
Well Spacing Optimization Technology For Coalbed Methane Horizontal Wells,
2025
College for Elite Engineers, China University of Geosciences, Wuhan 430074, China; PetroChina Hubei Oilfield Company, Renqiu 062552, China
Well Spacing Optimization Technology For Coalbed Methane Horizontal Wells, Wang Yuting, Yang Yanhui, Zhang Cong, Wang Xiuwei, Liu Zhong, Chen Jiale, Dong Qing, Sun Tao, Zhang Wuchang, Li Kexin, Wang Qi
Coal Geology & Exploration
Background Well spacing design directly affects the resource utilization and exploitation benefits of blocks. Rational well spacing design plays a significant role in the commercial exploitation of coalbed methane (CBM) fields. Since the beginning of China’s 14th Five-Year Plan, blocks for CBM production in the southern Qinshui Basin have experienced a gradual increase in burial depth, a progressive decline in permeability, and a constant update of primary exploitation technology. Consequently, traditional well spacings fail to meet the requirements for field CBM exploitation any longer. Methods This study investigated the western Qinnan – eastern Mabi block by combining numerical simulations with …
