Open Access. Powered by Scholars. Published by Universities.®
- Institution
- Keyword
-
- Gas (251)
- And Energy; Structural Materials; Sustainability (248)
- Energy Systems; Environmental Indicators and Impact Assessment; Environmental Monitoring; Mining Engineering; Oil (248)
- Numerical simulation (90)
- Coalbed methane (48)
-
- Coal mine (40)
- Ordos Basin (33)
- Coalbed methane (CBM) (31)
- Deep learning (28)
- Gas drainage (28)
- Pore structure (28)
- Deep coalbed methane (CBM) (27)
- Permeability (27)
- Deep coalbed methane (25)
- Coal (24)
- Hydraulic fracturing (24)
- Tar-rich coal (23)
- Directional drilling (21)
- Underground coal mine (21)
- Machine learning (19)
- Horizontal well (16)
- Qinshui Basin (16)
- Open-pit coal mine (14)
- Rock burst (14)
- Shale gas (13)
- Underground coal gasification (UCG) (13)
- United States (13)
- Coal mining (12)
- Fractal dimension (12)
- Fracture (12)
- Publication Year
- Publication
-
- Coal Geology & Exploration (1822)
- World of Coal Ash Proceedings (580)
- Journal of Sustainable Mining (202)
- Public Lands Mineral Leasing: Issues and Directions (Summer Conference, June 10-11) (16)
- UMR-MEC Conference on Energy / UMR-DNR Conference on Energy (4)
-
- Federal Lands, Laws and Policies and the Development of Natural Resources: A Short Course (Summer Conference, July 28-August 1) (3)
- Arkansas Scholarly Editions (1)
- Energy Field Tour 2003 (August 11-16) (1)
- Environmental Science Faculty Publications (1)
- LSU Doctoral Dissertations (1)
- Marine Affairs Theses and Major Papers (1)
- University of Nebraska-Lincoln Libraries: Faculty Publications (1)
- Publication Type
- File Type
Articles 511 - 540 of 2633
Full-Text Articles in Mining Engineering
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
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 …
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
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
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 …
Table Of Contents, The Editors
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
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 …
Technical Advances And Research Directions Of Borehole Geophysical Prospecting For Coal Mines, Cheng Jianyuan, Yan Yu, Li Yuteng, Wang Pan, Zhao Rui, Jiang Bici
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
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. …
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
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 …
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
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 …
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
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
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
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 …
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
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 …
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
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 …
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
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 …
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
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 …
Prediction Of Geological And Engineering Integrated Sweet Spots Of Deep Coalbed Methane, Chen Zhengrong, Liu Wei, Zhu Xueshen, Tian Yongjing, Xie Xin
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 …
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
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 …
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
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 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
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 …
Mechanisms And Collaborative Prevention And Control Techniques For Various Disasters In Coal Seam Roofs, Zheng Kaige, Zhang Jian, Sun Siqing, Chen Dongdong, Wang Zeyang
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
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 …
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
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
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
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
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 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
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 …
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
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
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
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 …