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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 …


Geochemical Nature Of The Geothermal Water From Lanzhou Basin: Implications For The Genesis Of Shallow Helium-Bearing Fluids, Tang Jianzhou, Wang Shuangming, Zhang Zhicheng, Li Ke, Li Changpeng Jun 2025

Geochemical Nature Of The Geothermal Water From Lanzhou Basin: Implications For The Genesis Of Shallow Helium-Bearing Fluids, Tang Jianzhou, Wang Shuangming, Zhang Zhicheng, Li Ke, Li Changpeng

Coal Geology & Exploration

Objective and Methods Investigations on the geochemical nature of geothermal water are vital to the comprehension of the origin of helium-rich fluids in shallow basins. To address this issue, this paper reports the results of the chemical analysis, H-O isotopes and 14C ages from geothermal water and soluble gas components from the well BY-1 in Lanzhou Basin, northeastern margin of Qinghai Tibet Plateau. Chemical analysis of geothermal water samples reveals that the chemical type of geothermal water is NaCl. The show δD value of –78‰, high δ18O value (–8.7‰), low 3H value (<0.4TU), and old 14C …


Prediction Of Geological And Engineering Integrated Sweet Spots Of Deep Coalbed Methane, Chen Zhengrong, Liu Wei, Zhu Xueshen, Tian Yongjing, Xie Xin Jun 2025

Prediction Of Geological And Engineering Integrated Sweet Spots Of Deep Coalbed Methane, Chen Zhengrong, Liu Wei, Zhu Xueshen, Tian Yongjing, Xie Xin

Coal Geology & Exploration

Objective Deep coalbed methane (CBM) has emerged as a hot topic in CBM resource development. However, deep CBM has characteristics such as great burial depths, complex stress environments, and strong reservoir heterogeneity, which seriously restrict sweet spot prediction and accurate well location deployment in its large-scale exploitation. Methods This study investigated a deep CBM field along the eastern margin of the Ordos Basin. Using sonic, density, and caliper logging, this study developed a coal structure index model for deep coals. By introducing the coal structure index based on the coal structure differences in deep coal seams and combining factors including …


Impacts Of Metakaolin And Fly Ash On The Performance Of Cement-Based Grouting Materials In Anchoring Engineering, Cheng Zhiyuan, Yang Junpeng, Xue Wei, Wei Daidong, Wang Yimin Jun 2025

Impacts Of Metakaolin And Fly Ash On The Performance Of Cement-Based Grouting Materials In Anchoring Engineering, Cheng Zhiyuan, Yang Junpeng, Xue Wei, Wei Daidong, Wang Yimin

Coal Geology & Exploration

Objective The filling of grouting materials plays a significant role in ensuring the performance of anchoring structures. This study aims to further enhance the fluidity of grouting materials, reduce their dry shrinkage in the curing process, and ensure complete filling. This will help improve the bonding property between the anchoring body and the rock and soil mass to be reinforced. Methods Using cement as the primary material, as well as fly ash and metakaolin as admixtures, this study designed and prepared 20 groups of binary and ternary mixtures and one control group. Through tests of the fluidity, bleeding ratios, and …


Diffusion Mechanisms Of Coal-Measure Helium And Their Implications For Helium Accumulation: A Case Study Of The Taiyuan Formation, Northern Qinshui Basin, China, Ma Yong, Xin Zhiyuan, Chen Jianfa, Li Yuhong, Zhang Xiutao, Jiang Haojie, Chen Zeya Jun 2025

Diffusion Mechanisms Of Coal-Measure Helium And Their Implications For Helium Accumulation: A Case Study Of The Taiyuan Formation, Northern Qinshui Basin, China, Ma Yong, Xin Zhiyuan, Chen Jianfa, Li Yuhong, Zhang Xiutao, Jiang Haojie, Chen Zeya

Coal Geology & Exploration

Objective The global helium-rich gas reservoirs are dominated by conventional natural gas reservoirs. In recent years, helium-bearing natural gas has been discovered in the Carboniferous-Permian coal measures in the Ordos Basin and surrounding regions, revealing the resource potential of coal-measure helium. However, there is almost a total lack of studies on mechanisms underlying the diffusion and migration of coal-measure helium. This severely restricts further research on the accumulation patterns of coal-measure helium.Methods This study investigated a coal seam in the Taiyuan Formation in the northern Qinshui Basin and mudstones in the coal seam roof. Using physical diffusion experiments on …


Physical Simulation Experiments On Competitive Dissolution Of Helium In Helium-Containing To Helium-Rich Gas Reservoirs, Zou Yi, Luo Qingyong, Chen Jianfa, Zou Huayao, Du Tao, Liu Xiaoqiang, Cai Xinyong, Yu Chengming, Fang Zilong Jun 2025

Physical Simulation Experiments On Competitive Dissolution Of Helium In Helium-Containing To Helium-Rich Gas Reservoirs, Zou Yi, Luo Qingyong, Chen Jianfa, Zou Huayao, Du Tao, Liu Xiaoqiang, Cai Xinyong, Yu Chengming, Fang Zilong

Coal Geology & Exploration

Background and Purpose Helium is widely applied in high-tech and scientific research fields due to its unique physicochemical properties. Formation water plays a key role in helium migration and enrichment. Typically, in the form of dissolved gas, helium is transported in pores or fractures by formation water. When helium-rich fluids migrate to shallow natural gas reservoirs, helium will experience dissolution and desorption exchange with other gases. This process is affected by formation temperature, pressure, and water salinity, as well as the competitive dissolution between helium and other gases. However, there is a lack of studies on the mechanisms underlying the …


Backfill-Strip Mining And Co2 Mineralization Sequestration In Coal Mine Goaves: A Synergetic Method And Its Key Technologies, Zhu Mengbo, Liu Lang, Wang Shuangming, Wei Baoning, Rong Ruoyu, Zhang Wenzhong, Zhuang Dengdeng, Jia Qifeng Jun 2025

Backfill-Strip Mining And Co2 Mineralization Sequestration In Coal Mine Goaves: A Synergetic Method And Its Key Technologies, Zhu Mengbo, Liu Lang, Wang Shuangming, Wei Baoning, Rong Ruoyu, Zhang Wenzhong, Zhuang Dengdeng, Jia Qifeng

Coal Geology & Exploration

Objective Coals serve as both the cornerstone of China’s energy security and important industrial raw materials. However, their mining and utilization tend to cause ecological and environmental problems such as CO2 emissions, the generation of solid wastes, and land subsidence. This necessitates reforming coal mining methods to promote the green, low-carbon, and sustainable development of China’s coal industry.Methods Through the comparative analysis of the conditions of CO2 sequestration in goaves corresponding to the caving, room-and-pillar (also known as knife-pillar), and backfill mining methods, this study developed a synergetic method for backfill-strip mining and CO2 mineralization sequestration …


A Visual Positioning Method For Tunnel Boring Machines In Underground Coal Mines Based On Anchor Net Features, Zhang Xuhui, Chi Yunkai, Du Yuyang, Jiang Junying, Yang Wenjuan, Zhao Youjun, Wan Jicheng, Wang Yanqun, Tian Chenhui Jun 2025

A Visual Positioning Method For Tunnel Boring Machines In Underground Coal Mines Based On Anchor Net Features, Zhang Xuhui, Chi Yunkai, Du Yuyang, Jiang Junying, Yang Wenjuan, Zhao Youjun, Wan Jicheng, Wang Yanqun, Tian Chenhui

Coal Geology & Exploration

Background Precise positioning of tunnel boring machines (TBMs) in underground coal mines plays a fundamental role in the automated and intelligent guidance and control of fully mechanized heading face. However, traditional visual positioning methods show limited application effects in underground roadways due to their narrow and enclosed spaces, insufficient illumination, and sparse textures. This study proposed a visual positioning method for TBMs in underground coal mines based on anchor net features.Methods A three-stream depthwise separable convolutional neural network (TSCR-NET) for image enhancement was employed to estimate the reflection, illumination, and noise in images individually. Through illumination adjustment while suppressing …


Table Of Contents, The Editors Jun 2025

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.


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 …


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 …


Impacts Of The Hydrochemical Characteristics Of Coal Seam Water On The Structures And Metabolic Functions Of Microbial Communities, Wang Gaohao, Duan Shengjie, Wang Bei, Niu Guobin, Liang Yongping, Yu Feilong, Ma Kai, Zhao Weizhong May 2025

Impacts Of The Hydrochemical Characteristics Of Coal Seam Water On The Structures And Metabolic Functions Of Microbial Communities, Wang Gaohao, Duan Shengjie, Wang Bei, Niu Guobin, Liang Yongping, Yu Feilong, Ma Kai, Zhao Weizhong

Coal Geology & Exploration

Background The core of coalbed methane (CBM) bioengineering is to inject bio-fracturing fluids rich in efficient methanogenic bacteria into coal reservoirs to promote the conversion of coals to methane. However, the relationships of the hydrochemical characteristics of coal seam water with the structures and metabolic functions of microbial communities remain unclear. Methods This study investigated coal seam water from 12 typical mining areas in Ningxia. Based on microbial classification and sequencing, as well as statistical analysis, this study explored the relationships of pH, anions, cations, and chemical oxygen demand (COD) of coal seam water with the structures and metabolic functions …


Construction And Application Of A Model For Drainage Via Directional Boreholes Against Water Hazards In Deep Vertical Shafts, Zhao Chunhu, Zhu Mingcheng, Ji Yadong, Wang Shidong, Zhang Wenzhong, Zhu Kaipeng, Liu Yingfeng, Shang Hongbo, Li Chaofeng, Fan Min, Li Kai May 2025

Construction And Application Of A Model For Drainage Via Directional Boreholes Against Water Hazards In Deep Vertical Shafts, Zhao Chunhu, Zhu Mingcheng, Ji Yadong, Wang Shidong, Zhang Wenzhong, Zhu Kaipeng, Liu Yingfeng, Shang Hongbo, Li Chaofeng, Fan Min, Li Kai

Coal Geology & Exploration

Background Vertical shafts are typically employed in the deep mining areas of Jurassic coalfields in western China. However, the direct exposure of extremely thick Cretaceous aquifers frequently leads to significant water inflow in shafts. Meanwhile, the continuous sand-carrying water inflow and scouring in vertical shafts pose serious safety hazards to the overall quality of shaft walls. Methods In underground water exploration and discharge boreholes, water outlets are below the floors of aquifers to be drained. This allows unpowered water discharge. In other words, water can flow out naturally. By fully leveraging this advantage, combined with the favorable condition of spatial …


Diffusion Mechanisms Of Power-Law Grouts In Water-Rich Sand Layers During Permeation Grouting, Xie Bao, Cheng Hua, Wang Xuesong, Li Mingjing, Liu Xiangyang, Han Xueyu May 2025

Diffusion Mechanisms Of Power-Law Grouts In Water-Rich Sand Layers During Permeation Grouting, Xie Bao, Cheng Hua, Wang Xuesong, Li Mingjing, Liu Xiangyang, Han Xueyu

Coal Geology & Exploration

Objective This study aims to clarify the spherical diffusion patterns of power-law grouts in water-rich sand layers during permeation grouting and their influential factors. To this end, permeation grouting experiments were conducted to gain insights into the quantitative impacts of varying grouting parameters on grout diffusion.Methods Using model experiments on spherical diffusion during permeation grouting, this study analyzed the macroscopic diffusion morphologies and microscopic infilling effects of grouts, as well as the trends of permeation and soil pressures during grouting. Then, based on the spherical diffusion equations for permeation grouting that consider multi-effect coupling, this study analyzed the factors …


A Method For Efficient Virtual-Physical Synchronization Of The Digital Twin System Of An Excavation-Supporting Robot Cluster Targeting Coal Pillars Between Mining Faces, Mao Qinghua, Sima Junlei, Ma Hongwei, Wang Chuanwei, Chen Yanzhang, Guo Wenjin, Cui Wenda, Cheng Jiashuai May 2025

A Method For Efficient Virtual-Physical Synchronization Of The Digital Twin System Of An Excavation-Supporting Robot Cluster Targeting Coal Pillars Between Mining Faces, Mao Qinghua, Sima Junlei, Ma Hongwei, Wang Chuanwei, Chen Yanzhang, Guo Wenjin, Cui Wenda, Cheng Jiashuai

Coal Geology & Exploration

Objective Virtual models for excavation-supporting robot clusters targeting coal pillars between mining faces encounter challenges like a large data size and anomalies in data transmission, which lead to poor virtual-physical synchronization. This study proposed a method for efficient virtual-physical synchronization of the digital twin (DT) system of an excavation-supporting robot cluster using 3D model lightweighting and a trajectory prediction and correction model. Methods Fit-controlling vertices were defined, and their collapse cost factor was introduced to improve the quadratic error metric (QEM) algorithm and to constrain the lightweighting process of the 3D model of an assembly while maintaining fits between components. …


An Improved Mp-Nmo Correction Method Based On Multiparameter Fitting And Its Application, Yang Xiaohui, Yu Pengfei, Zhang Jiawei May 2025

An Improved Mp-Nmo Correction Method Based On Multiparameter Fitting And Its Application, Yang Xiaohui, Yu Pengfei, Zhang Jiawei

Coal Geology & Exploration

Objective and Methods Normal moveout (NMO) correction is a core step in seismic data processing. However, the conventional NMO correction method tends to cause wavelet stretching when processing wide-angle or large-offset seismic data, leading to degraded stacking quality and distorted amplitude variation with offset (AVO) attributes. Although the matching pursuit (MP)-NMO correction method can mitigate the stretching effect, it will cause lateral discontinuity due to overlapping seismic events. Therefore, this study developed an improved MP-NMO correction method based on multiparameter fitting. Specifically, during MP decomposition, cubic polynomial fitting was applied to the amplitude, frequencies, and phases of wavelets from the …


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 …