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Full-Text Articles in Engineering

Construction And Application Of A Tcn-Lstm-Svm-Based Time Series Prediction Model For Water Inflow In Coal Seam Roofs, Liu Xuan, Ji Yadong, Zhu Kaipeng, Zhao Chunhu, Li Kai, Li Chaofeng, Yuan Chenhan, Li Panpan, Yan Pengzhen Jun 2025

Construction And Application Of A Tcn-Lstm-Svm-Based Time Series Prediction Model For Water Inflow In Coal Seam Roofs, Liu Xuan, Ji Yadong, Zhu Kaipeng, Zhao Chunhu, Li Kai, Li Chaofeng, Yuan Chenhan, Li Panpan, Yan Pengzhen

Coal Geology & Exploration

Background The accurate prediction of mine water inflow plays a significant role in the prevention and control of water hazards and the safe and efficient production in coal mines. Methods To construct a prediction model of water inflow in mines under threat of water hazards from extremely thick sandstones aquifer in West China, this study investigated a typical mine (also referred to as the studied mine) severely affected by such water hazards in the Binchang mining area of Shaanxi Province. The correlation between the mining footage and water inflow of the mining face was selected as the characteristic variable for …


Influencing Patterns Of Low-Temperature Nitrogen On The Pore Structure And Oxidation Characteristics Of Lignite, Xie Shuliang, Wang Gang, Qu Qingdong, Liu Hao, Sun Lulu Jun 2025

Influencing Patterns Of Low-Temperature Nitrogen On The Pore Structure And Oxidation Characteristics Of Lignite, Xie Shuliang, Wang Gang, Qu Qingdong, Liu Hao, Sun Lulu

Coal Geology & Exploration

Objective During fire prevention and extinguishment for mines, injecting normal-temperature nitrogen into goaves can only play an inerting role. Meanwhile, the preparation of liquid nitrogen is complicated and costly. Therefore, in the Wudong Coal Mine in Xinjiang, low-temperature gaseous nitrogen of –40 ℃ was prepared using nitrogen cooling devices and then injected into goaves to prevent the spontaneous combustion of residual coals. However, the influencing patterns of low-temperature nitrogen on the pore structures and oxidation characteristics of residual coals in goaves remain poorly understood. This tends to affect the prediction and forecast of the secondary oxidation of residual coals in …


Mechanisms Underlying Differential Helium Enrichment In Shale Gas Of Varying Structural Styles In The Southeastern Sichuan Basin, Xin Zhiyuan, Chen Jianfa, Wang Jie, Ma Yong Jun 2025

Mechanisms Underlying Differential Helium Enrichment In Shale Gas Of Varying Structural Styles In The Southeastern Sichuan Basin, Xin Zhiyuan, Chen Jianfa, Wang Jie, Ma Yong

Coal Geology & Exploration

Objective Shale gas reservoirs hold considerable helium reserves despite relatively low helium abundance, establishing them as a critical replacement for helium production growth. The southeastern Sichuan Basin exhibits diverse structural styles with varying preservation conditions, leading to an unclear understanding of the distribution characteristics and enrichment patterns of helium in shale gas. Determining the mechanisms behind the differential helium enrichment in shale gas is significant for the effective utilization of helium in shale gas.Methods Focusing on the typical shale gas reservoirs of different structural styles in the southeastern Sichuan Basin, this study explored the mechanisms underlying differential helium accumulation …


Technical Advances And Research Directions Of Borehole Geophysical Prospecting For Coal Mines, Cheng Jianyuan, Yan Yu, Li Yuteng, Wang Pan, Zhao Rui, Jiang Bici Jun 2025

Technical Advances And Research Directions Of Borehole Geophysical Prospecting For Coal Mines, Cheng Jianyuan, Yan Yu, Li Yuteng, Wang Pan, Zhao Rui, Jiang Bici

Coal Geology & Exploration

Background High-precision and long-distance exploration of geological conditions is required for coal extraction and disaster prevention in coal mines. However, traditional drilling and geophysical prospecting methods face technical bottlenecks such as insufficient exploration accuracy and limited exploration ranges. Borehole geophysical prospecting technology integrates the reliable and straightforward axial results of drilling with the high-resolution transverse results of geophysical prospecting, providing technical support for safe, efficient, and intelligent coal mining. Based on the construction spaces, this study categorizes borehole geophysical prospecting technology into four types: i.e., intra-borehole, inter-borehole, borehole-surface, and borehole-roadway. Furthermore, it presents the primary advances and applicable conditions of …


Implications Of Helium Accumulation Models In Helium-Rich Basins In China For The Enrichment And Exploration Of Helium In Coal Measures, Li Yunbo, Wang Chengtao, Song Dangyu, Shi Xiaowei, Wang Rongqi Jun 2025

Implications Of Helium Accumulation Models In Helium-Rich Basins In China For The Enrichment And Exploration Of Helium In Coal Measures, Li Yunbo, Wang Chengtao, Song Dangyu, Shi Xiaowei, Wang Rongqi

Coal Geology & Exploration

Background Helium is a strategic resource in serious short supply in China, and intensifying its exploration is crucial to national resource security. China enjoys abundant coal measure gas and significant potential for associated helium accumulation. However, relevant research remains in its infancy. Methods Based on a summary and analysis of helium generation, migration, and accumulation theories in natural gas reservoirs, this study systematically investigated the enrichment patterns of helium in coal measures and proposed exploration targets. Results and Conclusions The insights reveal that the helium resources in China exhibit a distribution pattern of zoning in both north-south and east-west directions. …


Advances In Research On Noble Gas As Tracers Of Geofluids And Helium Enrichment, Gao Yu, Liu Quanyou, Zhu Dongya, Wu Xiaoqi, Li Pengpeng Jun 2025

Advances In Research On Noble Gas As Tracers Of Geofluids And Helium Enrichment, Gao Yu, Liu Quanyou, Zhu Dongya, Wu Xiaoqi, Li Pengpeng

Coal Geology & Exploration

Background Noble gases emerge as significant tools for tracing the sources and evolutionary processes of geofluids due to their chemical inertness and different isotopic compositions across varying reservoirs. Helium serves as a noble gas tracer and a scarce resource, and its enrichment mechanisms and exploration potential have attracted wide attention.Methods Based on a summary of the geochemical data of typical gas reservoirs, volcanic gases, and surface hot springs at home and abroad, this study analyzed the interfering factors and end-member value screening in the source apportionment of noble gases. Furthermore, it summarized the applications of noble gas isotopes in …


Dominant Factors Causing Helium Deficiency In Coal-Measure Natural Gas In The Kuqa Depression, Tarim Basin, Liu Jiarun, Liu Quanyou, Li Pengpeng, Gao Yu, Lü Jiahao Jun 2025

Dominant Factors Causing Helium Deficiency In Coal-Measure Natural Gas In The Kuqa Depression, Tarim Basin, Liu Jiarun, Liu Quanyou, Li Pengpeng, Gao Yu, Lü Jiahao

Coal Geology & Exploration

Background Helium is identified as a scarce strategic resource, having found widespread applications in high-tech fields such as high-end manufacturing, aerospace, and national defense due to its stable chemical properties and low boiling point. The Kuqa Depression in the Tarim Basin is a significant natural gas production base in China. Determining the distribution characteristics and controlling factors of helium in coal-measure natural gas in the Kuqa Depression holds great significance.Methods Using two helium resource assessment methods and geological data, this study explored the dominant factors causing helium deficiency in the coal-measure natural gas in the Kuqa Depression.Results and …


Resource Potential And Extraction Technique Design For Helium In Coal Measures, Wang Lei, Tang Maoyin Jun 2025

Resource Potential And Extraction Technique Design For Helium In Coal Measures, Wang Lei, Tang Maoyin

Coal Geology & Exploration

Back ground Helium is an important strategic scarce resource. Presently, helium used in industry originates primarily from natural gas. In contrast, helium in coal measures, generally emerging as coalbed methane (CBM) with a high helium content, serves as a vital supplement to conventional helium resources. In industry, helium extraction from boil off gas (BOG) during natural gas liquefaction is recognized as an important way to obtain helium resources. However, existing studies on helium in coal measures mostly focus on the genesis, enrichment patterns, and geochemical characteristics of helium, while there is a lack of studies on its resource characteristics and …


Effectiveness Assessment And Spatial Distribution Characteristics Of Helium Source Rocks In The Shixi Block Along The Eastern Margin Of The Ordos Basin, Chang Yangmei, Liu Chao, Sun Beilei Jun 2025

Effectiveness Assessment And Spatial Distribution Characteristics Of Helium Source Rocks In The Shixi Block Along The Eastern Margin Of The Ordos Basin, Chang Yangmei, Liu Chao, Sun Beilei

Coal Geology & Exploration

Background Helium gas serves as a significant rare strategic resource. In China, helium resources are relatively scarce and dependent heavily on imports. Therefore, there is a pressing need for the exploration and exploitation of helium resources. Helium source rocks provide a material basis for the formation of helium resources. The Zijinshan pluton serves as a principal source of coal-measure helium along the eastern margin of the Ordos Basin. Previous studies reveal that helium in natural gas within the Shixi Block originates primarily from the decay of radioactive elements in the deep part of the Jianjiagou-Zijinshan plutons. However, there is a …


Analyzing The Permeability Enhancement Effect Of Hydraulic Slotting For Low-Permeability Coal Seams Based On A Stress-Diffusion-Seepage Coupling Model, Zhang Hongtu, Zhou Tian, Wang Dengke, Li Botao, Luo Yong, Pan Rongsheng, Tang Jiahao, Lu Weiyong Jun 2025

Analyzing The Permeability Enhancement Effect Of Hydraulic Slotting For Low-Permeability Coal Seams Based On A Stress-Diffusion-Seepage Coupling Model, Zhang Hongtu, Zhou Tian, Wang Dengke, Li Botao, Luo Yong, Pan Rongsheng, Tang Jiahao, Lu Weiyong

Coal Geology & Exploration

Objective and Methods This study aims to improve the permeability enhancement effect of coal seams for gas drainage. Targeting the soft, low-permeability coal seams with complex gas occurrence conditions in the Baiping mining area and considering the impacts of effective stress, gas migration, actual gas effects, and tortuosity, this study constructed a stress-diffusion-seepage coupling model based on the pore-fracture dual medium assumption. Using the coupling model, this study simulated the variation patterns of gas content in coal seams during gas drainage under varying gas contents and borehole spacings. Through field tests under different permeability enhancement measures and unloaded coal amounts …


Chemical Temporary Plugging-Based Full-Bore Reconstruction Technology For Old Wellbores For The Collaborative Production Of Tight-Sand Gas And Deep Coalbed Methane, Yang Fan, Tan Zhanglong, Hu Jiachen, An Qi, Li Yu, Yang Ruiyue, Lin Junwen, Sun Zening, Jing Meiyang Jun 2025

Chemical Temporary Plugging-Based Full-Bore Reconstruction Technology For Old Wellbores For The Collaborative Production Of Tight-Sand Gas And Deep Coalbed Methane, Yang Fan, Tan Zhanglong, Hu Jiachen, An Qi, Li Yu, Yang Ruiyue, Lin Junwen, Sun Zening, Jing Meiyang

Coal Geology & Exploration

Objective In China, the Ordos Basin boasts abundant coal-measure gas resources, holding considerable potential for resource development. As the development deepens, the proportion of depleted, stripper, and inefficient wells for tight-sand gas in coal measures has gradually decreased year by year. The collaborative production of tight-sand gas and deep coalbed methane (CBM) has emerged as a significant approach to effectively releasing production capacity.Methods To achieve the reconstruction of old wellbores and commingled production of new and old layers, this study proposed a technology of chemical temporary plugging-based full-bore reconstruction of old wellbores of tight-sand gas combined with the large-scale …


The Borehol Wall Image Digital Description Method Of The Overlying Rock Structural Planes Evdution Process In Deep Mining, Wang Jinchao, Zou Junpeng, Li Shenghai, Wang Chao, Li Xiaobin Jun 2025

The Borehol Wall Image Digital Description Method Of The Overlying Rock Structural Planes Evdution Process In Deep Mining, Wang Jinchao, Zou Junpeng, Li Shenghai, Wang Chao, Li Xiaobin

Coal Geology & Exploration

Objective In China, as mineral resource mining is increasingly expanding towards the deep parts of the Earth, the safe and efficient exploitation of deep resources has become a major strategic and technological challenge at the national level to be addressed urgently. Understanding the movement patterns of mining-affected strata in deep environments will assist in improving the intelligent prevention and control of mine disasters, thereby ensuring the safe and efficient exploitation of deep resources. Methods Targeting the complex and diverse forms of the overburden’s structural planes in deep mining, as well as a lack of characterization methods tailored to the evolutionary …


Current Status And Future Trends Of Seismic Prediction And Assessment Technology For Coalbed Methane Reservoirs, Wu Haibo, Zhang Pingsong, Xu Shi’Ang, Huang Yaping, Dong Shouhua, Cheng Yan, Li Donghui, Zhang Sheng, Zhang Min Jun 2025

Current Status And Future Trends Of Seismic Prediction And Assessment Technology For Coalbed Methane Reservoirs, Wu Haibo, Zhang Pingsong, Xu Shi’Ang, Huang Yaping, Dong Shouhua, Cheng Yan, Li Donghui, Zhang Sheng, Zhang Min

Coal Geology & Exploration

Background The seismic prediction and assessment technology for coalbed methane (CBM) reservoirs has undergone rapid development for over three decades, playing an indispensable role in CBM exploration. Methods This study reviews the development history and current status of core technologies within the seismic prediction and assessment technical system for CBM reservoirs, including seismic-petrophysical tests, modeling and inversion, seismic wavefield simulation, seismic amplitude versus offset (AVO) inversion and seismic attribute inversion, and integrated seismic prediction of the sweet spot areas of CBM reservoir resources and engineering. Furthermore, this study delves into the impacts and limitations of the characteristics of CBM reservoirs, …


A Method Integrating A Non-Stationary Random Field For Constrained Inversion Of Csamt Data, Dai Qianwei, Guo Luyao, Wu Yun, Xiong Zhexian, Duan Dan, Bao Zhonglin, Wu Hongfei, Hao Fengyun Jun 2025

A Method Integrating A Non-Stationary Random Field For Constrained Inversion Of Csamt Data, Dai Qianwei, Guo Luyao, Wu Yun, Xiong Zhexian, Duan Dan, Bao Zhonglin, Wu Hongfei, Hao Fengyun

Coal Geology & Exploration

Objective The inversion of controlled-source audio-frequency magnetotelluric (CSAMT) data remains challenging due to two key issues: computational efficiency and resolution. To tackle these two issues, especially the over-smoothing effect caused by traditional regularization methods in estimating complex geological structures, this study proposed an improved regularization inversion method to reflect the spatial distribution characteristics of subsurface physical property parameters more accurately. Methods The proposed method was developed using the method for establishing the stochastic partial differential equation (SPDE) based on the Matérn covariance function. By introducing vector fields and the shape parameters of a range ellipse, this method fully considered both …


A Phase Transition-Induced Fracturing Permeability Enhancement Technology Using Carbon Dioxide Capsules For Low-Permeability Coal Seams And Its Application, Li Mao, Fan Xinchuan, Fu Hui May 2025

A Phase Transition-Induced Fracturing Permeability Enhancement Technology Using Carbon Dioxide Capsules For Low-Permeability Coal Seams And Its Application, Li Mao, Fan Xinchuan, Fu Hui

Coal Geology & Exploration

Objective and Methods To address engineering challenges like high gas content, high pressure, and low drainage efficiency in the mining of low-permeability coal seams, this study developed a phase transition-induced fracturing and permeability enhancement technology using carbon dioxide (CO2) capsules for low-permeability coal seams. This technology leverages the feature that CO2 transitions into the supercritical state under high pressure. A capsule encapsulating critical CO2 is placed into a conduit, which is then placed within a coal seam. Subsequently, phase transition-induced blasting is triggered using a heating blasting start device. Consequently, liquid CO2 vaporizes rapidly and …


Characteristics And Control Modes Of Geothermal Fields In Deep Coal Reservoirs In The Linxing-Shenfu Block, Xu Lifu, Bai Yuhu, Xu Bingxiang, Hu Weiqiang, Chen Jianqi, Li Yong May 2025

Characteristics And Control Modes Of Geothermal Fields In Deep Coal Reservoirs In The Linxing-Shenfu Block, Xu Lifu, Bai Yuhu, Xu Bingxiang, Hu Weiqiang, Chen Jianqi, Li Yong

Coal Geology & Exploration

Objective Geothermal fields serve as a crucial geological condition controlling the phases and seepage of deep coalbed methane (CBM). Investigating geothermal fields facilitates the assessment and efficient development of deep CBM resources.Methods This study explored the Nos. 8 and 9 coal seams in the Linxing-Shenfu block using data from drilling, well logging, well tests, and experiments. Specifically, this study summarized the regional distribution patterns of geothermal fields in deep coal reservoirs in the block, analyzed the impacts of the geothermal fields on the gas-bearing and physical properties of the reservoirs, and revealed the controlling factors and mechanisms of the …


Dynamic Evolutionary Patterns Of High-Temperature Steam Seepage And Thermal Strains Of Coals During Heat Injection, Li Zhiqiang, Zhang Ningchao, Chen Jinsheng, Chen Liwei, Feng Wenxiang, Liu Longwei, Wang Yungang May 2025

Dynamic Evolutionary Patterns Of High-Temperature Steam Seepage And Thermal Strains Of Coals During Heat Injection, Li Zhiqiang, Zhang Ningchao, Chen Jinsheng, Chen Liwei, Feng Wenxiang, Liu Longwei, Wang Yungang

Coal Geology & Exploration

Background Thermal stimulation of coal seams using high-temperature steam is recognized as a highly promising technology used to increase gas production. Steam permeability serves as a critical parameter for characterizing the injection capacity of thermal fluids. However, the seepage patterns and evolutionary mechanism of steam in coals remain unclear, and exploring these issues holds critical scientific significance for gas production enhancement via heat injection. Methods Through experiments on the seepage and thermal strains of coals during the injection of high-temperature steam performed using the steady-state method, this study investigated the dynamic time variation patterns of the steam permeability and thermal …


Assessing The Potential And Suitability Of Geothermal Resources Using Monte Carlo Simulation And Game-Based Combination Weighting Method, He Yixiang, Ding Pengpeng, Liu Shaohua, Wang Mingzhu, Zhu Lei May 2025

Assessing The Potential And Suitability Of Geothermal Resources Using Monte Carlo Simulation And Game-Based Combination Weighting Method, He Yixiang, Ding Pengpeng, Liu Shaohua, Wang Mingzhu, Zhu Lei

Coal Geology & Exploration

Background Geothermal energy in porous sandstone reservoirs is recognized as stable, efficient clean energy. However, these reservoirs feature heterogeneity and exploration uncertainty, posing serious challenges to probabilistic resource assessment and the identification of suitability for resource development.Methods This study investigated the geothermal resources in the Guantao Formation within the northwest Shandong plain. Using the volumetric method and Monte Carlo simulation, this study assessed the uncertainty of the resource potential. Then, considering the characteristics of geothermal resources, the attributes of geological structures, and the social economy, this study developed a multi-dimensional evaluation index system for the suitability of sandstone geothermal …


Table Of Contents, The Editors May 2025

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.


Sedimentary Patterns And Exploitation Practices Of Tight-Sand Gas Reservoirs In Coal Measure Strata: A Case Study Of The 3rd Submember Of The Second Member Of The Permian Shanxi Formation In The Daning-Jixian Block, Zhang Lei, Huang Li, Zhao Longmei, Wang Feng, Zhang Yixin, Shi Shi, Zhang Wen, Zhao Haoyang, Chen Tong, Tong Jiangnan May 2025

Sedimentary Patterns And Exploitation Practices Of Tight-Sand Gas Reservoirs In Coal Measure Strata: A Case Study Of The 3rd Submember Of The Second Member Of The Permian Shanxi Formation In The Daning-Jixian Block, Zhang Lei, Huang Li, Zhao Longmei, Wang Feng, Zhang Yixin, Shi Shi, Zhang Wen, Zhao Haoyang, Chen Tong, Tong Jiangnan

Coal Geology & Exploration

Background The third submember of the second member of the Permian Shanxi Formation (also referred to as the Shan 23 submember) in the Daning-Jixian block along the eastern margin of the Ordos Basin is identified as a primary target layer for tight-sand gas production in the block. In the early stage of the block development, play fairways were initially identified through fundamental studies on provenance areas and sedimentary systems. Accordingly, a gas field with an annual production of 10 × 108 m3 was constructed in the block. However, further exploitation reveals that the sandstones in the Shan …


Application Of A Uav-Borne Gpr System In The Detection Of Water Bodies And Cavities, Wang Ying, Sun Chenchen, Zhang Lu, Chen Yifei, Lu Song, Zhou Feng May 2025

Application Of A Uav-Borne Gpr System In The Detection Of Water Bodies And Cavities, Wang Ying, Sun Chenchen, Zhang Lu, Chen Yifei, Lu Song, Zhou Feng

Coal Geology & Exploration

Objective and Methods The unmanned aerial vehicle (UAV)-borne ground-penetrating radar (GPR) system, enjoying the advantages of high resolution and non-contact detection, is applicable to the detection of water accumulation in coal seams and goaves in mines. Therefore, this study proposed a rapid detection method based on a UAV-borne air-coupled GPR system to enhance the exploration efficiency of mining areas and reduce the time and risks of manual explorations. Given the limitations of the test scenarios in actual coal mines, this study investigated the water body of the Fanxiong reservoir in Ezhou City and surrounding drainage culverts for equivalent validation, aiming …


Transparent Prevention And Control System For Water Hazards In Mine Floors Under Empowerment Based On Spatiotemporal Information Fusion, Liu Zaibin, Yan Junsheng, Wang Jianghong, Gao Yaoquan, Yang Hui, Bai Baojun, Lu Jingjin, Wang Hongwei, Wang Gang May 2025

Transparent Prevention And Control System For Water Hazards In Mine Floors Under Empowerment Based On Spatiotemporal Information Fusion, Liu Zaibin, Yan Junsheng, Wang Jianghong, Gao Yaoquan, Yang Hui, Bai Baojun, Lu Jingjin, Wang Hongwei, Wang Gang

Coal Geology & Exploration

Background Water hazards in coal mines frequently cause heavy casualties, severely affecting the safe mining of coal mines. Methods With the continuous advancements in both the construction of real scene 3D views and coal mine intelligentization, this study examined the development of the intelligent geological guarantee system for the Tangjiahui Coal Mine in Inner Mongolia, as well as the prevention and control of water hazards in the Ordovician limestones in the coal mine floor. Accordingly, this study elaborated on enhancing the prevention and control capacity against water hazards in coal mines during the mining cycle of a mining face using …


Experimental Study On Unloading Confining Pressure Deformation And Damage Failure Of Multi-Source Coal-Based Solid Waste Cemented Backfill, He Xiang, Wei Longqiang, Yang Ke, Zhang Tong, Zhang Cun, Zhang Zilong, Chen Yanjun May 2025

Experimental Study On Unloading Confining Pressure Deformation And Damage Failure Of Multi-Source Coal-Based Solid Waste Cemented Backfill, He Xiang, Wei Longqiang, Yang Ke, Zhang Tong, Zhang Cun, Zhang Zilong, Chen Yanjun

Coal Geology & Exploration

Objective The preparation of multi-source coal-based solid waste into filling materials for interval strip filling mining is one of the important means of green coal mining. The deformation and failure law of multi-source coal-based solid waste cemented backfill during strip coal pillar mining directly affects the stability of the stope.Methods Five typical solid wastes were mixed with cement to prepare cemented backfill. The conventional triaxial and constant axial pressure unloading confining pressure stress tests of backfill specimens were carried out. The stress-strain curves and failure characteristics of backfill under two stress loading paths were analyzed. The evolution law of …


Fluoride Ion Removal From Mine Water Via Nucleation Crystallization Pelleting Process, Zhang Xiyu, Dong Shuning, Wang Hao, Jin Pengkang, Wang Xiaodong, Wang Qiangmin, Zhang Tao May 2025

Fluoride Ion Removal From Mine Water Via Nucleation Crystallization Pelleting Process, Zhang Xiyu, Dong Shuning, Wang Hao, Jin Pengkang, Wang Xiaodong, Wang Qiangmin, Zhang Tao

Coal Geology & Exploration

Objective The mine water associated with coal mining tends to be rich in fluoride ions. If discharged directly without effective treatment, such water will cause severe pollution to regional ecology, affecting the quality of water resources and the stability of the ecosystem. Methods This study focuses on the challenging treatment of the fluoride pollution caused by coal mining-associated mine water. To overcome the bottlenecks including low efficiency and weak anti-interference of traditional methods for fluoride removal, this study designed a setup for fluoride removal using the nucleation crystallization pelleting (NCP) processing and proposed a novel fluoride removal method—NCP chemical precipitation. …


A Seismic Random Noise Suppression Method Based On Cnn-Mamba, Wei Xiujuan, Liu Xingye, Zhou Huailai May 2025

A Seismic Random Noise Suppression Method Based On Cnn-Mamba, Wei Xiujuan, Liu Xingye, Zhou Huailai

Coal Geology & Exploration

Background Seismic random noise suppression is recognized as a key step to improve the quality of seismic data. Data-driven deep learning provides an intelligent solution for the noise suppression. However, mainstream random noise intelligent methods based on convolutional neural networks (CNNs) are constrained by their local receptive fields. This limitation results in insufficient collaborative optimization between local details and macroscopic structures during denoising, further reducing the noise suppression accuracy. Transformer models, which are widely applied to global feature extraction, can effectively capture long-distance dependencies through the self-attention mechanism, theoretically overcoming the limitations of CNNs in global modeling. However, these models …


Historical Overview, Advancements, And Future Prospects Of Coalfield Structure Research In China, Cao Daiyong, Ju Yiwen, Xia Yucheng, Jiang Bo, Ning Shuzheng, Wei Yingchun, Wang Anmin, Li Xiaoming, Zhan Wenfeng, Li Huantong, Wang Lu, Cai Zhuocheng May 2025

Historical Overview, Advancements, And Future Prospects Of Coalfield Structure Research In China, Cao Daiyong, Ju Yiwen, Xia Yucheng, Jiang Bo, Ning Shuzheng, Wei Yingchun, Wang Anmin, Li Xiaoming, Zhan Wenfeng, Li Huantong, Wang Lu, Cai Zhuocheng

Coal Geology & Exploration

Background Coalfield structures represent a basic aspect of coalfield geology. In China, research into this domain has a history of over a century, yielding numerous results after undergoing exploration, learning, and innovation. These results have played a positive role in the long-term, stable coal supply in China. Amidst the ongoing energy structure optimization and the transformation and upgrading of coalfield geology in China, it is both practically and historically significant to review the history of coalfield structure research, summarize relevant experience, and contemplate future directions of the research under emerging circumstances.Methods Based on literature analysis, as well as the …


Mechanisms And Collaborative Prevention And Control Techniques For Various Disasters In Coal Seam Roofs, Zheng Kaige, Zhang Jian, Sun Siqing, Chen Dongdong, Wang Zeyang May 2025

Mechanisms And Collaborative Prevention And Control Techniques For Various Disasters In Coal Seam Roofs, Zheng Kaige, Zhang Jian, Sun Siqing, Chen Dongdong, Wang Zeyang

Coal Geology & Exploration

Objective The multistage sedimentary and tectonic evolution of coal seams in China has led to the formation of environments with the coexistence of multiple disasters including gas outbursts, water inrushes, and rock bursts. To address the chain evolution of these disasters induced by the coupling of high in situ stress, high water pressure, and intense mining under the condition of deep coal mining, this study systematically investigated the coupling mechanisms and collaborative prevention and control techniques of multiple dynamic disasters in coal seam roofs. Methods Based on the regional tectonic characteristics and the delineation of coal-bearing tectonic units, this study …


Mechanisms And Equation Improvement For Gas Seepage In Coal Seams Around Boreholes Subjected To High-Pressure Co2 Foam Fracturing, Pang Mingkun, Zhang Tianyu, Pan Hongyu, Song Xianfeng, Wu Shan, Zhang Tianjun May 2025

Mechanisms And Equation Improvement For Gas Seepage In Coal Seams Around Boreholes Subjected To High-Pressure Co2 Foam Fracturing, Pang Mingkun, Zhang Tianyu, Pan Hongyu, Song Xianfeng, Wu Shan, Zhang Tianjun

Coal Geology & Exploration

Objective The special low-porosity, low-permeability structures of high-gas-content coal seams restrict efficient gas drainage. To address this issue, this study accurately determined the seepage parameters of annularly fractured coals around boreholes subjected to CO2 foam fracturing to enhance both the design accuracy of boreholes for gas pre-drainage from coal seams and gas drainage efficiency. Methods Using an independently developed apparatus for gas seepage experiments on fractured coals around boreholes, this study investigated the coals with pores and fractures distributed in an annular pattern around boreholes from the perspective of varying initial pore structures. Specifically, this study analyzed the evolutionary …


Classification-Based Point Cloud Denoising And 3d Reconstruction Of Roadways, Chen Denghong, Pang Ning, Nie Wen, Feng Juqiang, Kan Jiliang, Zhang Jinjing May 2025

Classification-Based Point Cloud Denoising And 3d Reconstruction Of Roadways, Chen Denghong, Pang Ning, Nie Wen, Feng Juqiang, Kan Jiliang, Zhang Jinjing

Coal Geology & Exploration

Objective The point cloud denoising and 3D reconstruction of roadways serve as a key step in the digital modeling and analysis of roadways. However, the conventional algorithm based on single filtering fails to effectively remove the noise at varying scales from point clouds. Meanwhile, the existing 3D reconstruction algorithms suffer from low modeling accuracy and high susceptibility to distortion. These necessitate developing methods and technologies to obtain high-quality point cloud data and construct high-accuracy 3D models for roadways. Methods This study proposed an adaptive classification-based point cloud denoising algorithm using neighborhood radius (R), minimum neighborhood point number ( …


Dominant Geological And Engineering Factors Controlling The Productivity Of Horizontal Wells For Deep Coalbed Methane In The Southern Shenfu Block, Guo Guangshan, Liu Yancheng, Zhao Gang, Chen Zhaohui, Li Chen, Kang Lifang, Wang Yuchuan, Wang Jianan May 2025

Dominant Geological And Engineering Factors Controlling The Productivity Of Horizontal Wells For Deep Coalbed Methane In The Southern Shenfu Block, Guo Guangshan, Liu Yancheng, Zhao Gang, Chen Zhaohui, Li Chen, Kang Lifang, Wang Yuchuan, Wang Jianan

Coal Geology & Exploration

Objective The southern Shenfu block along the eastern margin of the Ordos Basin hosts one of the rare gas fields with reserves of over 100 billion cubic meters (bcm) in China, serving as a pilot demonstration area for the exploration and production of deep coalbed methane (CBM) conducted by the China National Offshore Oil Corporation (CNOOC). In this block, the gas production of horizontal wells is 2-10 times that of vertical wells. However, the horizontal wells are challenged by significantly different and rapidly declining gas production. Determining dominant factors controlling the productivity of horizontal wells for deep CBM is the …