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Full-Text Articles in Mining Engineering
Occurrence Pattern Of Adsorbed And Free Gas In Deep Coal Seams Under The Control Of Pore Structure: A Case Study Of The No. 8 Coal Seam In The Daning-Jixian Block Along The Eastern Margin Of The Ordos Basin, Bian Liheng, Shen Jian, Shi Rui, Zhang Wei, Ma Zhuang, Liang Xuemin, Dong Jiying, Zhu Peipei, Ma Tianyu
Occurrence Pattern Of Adsorbed And Free Gas In Deep Coal Seams Under The Control Of Pore Structure: A Case Study Of The No. 8 Coal Seam In The Daning-Jixian Block Along The Eastern Margin Of The Ordos Basin, Bian Liheng, Shen Jian, Shi Rui, Zhang Wei, Ma Zhuang, Liang Xuemin, Dong Jiying, Zhu Peipei, Ma Tianyu
Coal Geology & Exploration
Background Deep coalbed methane (CBM) holds an important strategic position in China's unconventional natural gas system. However, concerning deep CBM occurrence, there remains a lack of systematic quantitative understanding of the underlying mechanisms and the controlling effects of pore structure. Methods This study investigated high-rank coal samples collected at a burial depth of approximately 2000 m from the No. 8 coal seam in the Daning-Jixian block along the eastern margin of the Ordos Basin. Using multiscale pore characterization techniques, including low-temperature liquid nitrogen adsorption, high-pressure mercury injection, and low-temperature CO2 adsorption, the full-scale pore size distribution of the coal …
Intelligent Identification Of Deep Coal Macrolithotypes Based On Weighted Ensemble In Machine Learning: A Case Study Of The Shenmu Area, Ordos Basin, Yao Yuhao, Yang Zhaobiao, Huang Daojun, Wang Jianan, Dong Guodong, Chen Yilin, He Jinxian, Zhang Shang
Intelligent Identification Of Deep Coal Macrolithotypes Based On Weighted Ensemble In Machine Learning: A Case Study Of The Shenmu Area, Ordos Basin, Yao Yuhao, Yang Zhaobiao, Huang Daojun, Wang Jianan, Dong Guodong, Chen Yilin, He Jinxian, Zhang Shang
Coal Geology & Exploration
Objective Coal macrolithotype represents a key geological property in the exploration and recovery of deep coalbed methane (CBM) resources, and its accurate identification is of great significance for selecting the optimal geological and engineering sweet-spot intervals. However, conventional coal macrolithotype identification relies heavily on core observation, suffering from prohibitively high costs since core data are extremely valuable and thus feature a small sample size. Meanwhile, conventional log-based threshold methods face challenges in effectively characterizing the complex boundaries between coal macrolithotypes.Methods This study investigated the No. 8 coal seam of the Benxi Formation, Shenmu area, eastern Ordos Basin. Based on …
Sources And Occurrence Patterns Of Hydrocarbons In The Surrounding Rocks Of Coal Seams: A Case Study Of The Jurassic Yan'an Formation In The Xinzhuang Mine Field, Longdong Area, Zhang Peng, Chen Dongdong, Zhao Junfeng, Zheng Kaige, Wang Chunxin, Zhou Xingtian
Sources And Occurrence Patterns Of Hydrocarbons In The Surrounding Rocks Of Coal Seams: A Case Study Of The Jurassic Yan'an Formation In The Xinzhuang Mine Field, Longdong Area, Zhang Peng, Chen Dongdong, Zhao Junfeng, Zheng Kaige, Wang Chunxin, Zhou Xingtian
Coal Geology & Exploration
Objective and Methods This study aims to ascertain abnormal hydrocarbon outflows from the surrounding rocks of coal seams in the Jurassic Yan'an Formation within the Xinzhuang mine field in the Longdong area, southwestern Ordos Basin. Based on the fundamental principles of petroleum geology, sedimentology, and coal geology, this study systematically analyzed the sources, occurrence patterns, and primary controlling factors of hydrocarbons in the surrounding rocks of coal seams using methods including core observation, sample analysis, and statistical mapping. Results and Conclusions In the Xinzhuang mine field, hydrocarbon outflows are primarily identified in the floor of the No. 8 coal seam …
A Seismic Prediction Technology For Coalbed Methane Sweet Spots And Its Engineering Application In The Ordos Basin, Zhang Mengbo, Li Fei, Zhang Dong, Peng Jiankang, Cui Xiaojie, Ni Na, Long Shengfang, Tao Yu, Zhu Jun
A Seismic Prediction Technology For Coalbed Methane Sweet Spots And Its Engineering Application In The Ordos Basin, Zhang Mengbo, Li Fei, Zhang Dong, Peng Jiankang, Cui Xiaojie, Ni Na, Long Shengfang, Tao Yu, Zhu Jun
Coal Geology & Exploration
Objective Deep coalbed methane (CBM) reservoirs tend to exhibit significant tuning effects of thin interbeds, leading to challenging localization of actual coal seam boundaries, limited identification accuracy of micro-amplitude structures in the coal seam roof, and poor stability of the seismic responses of the reservoirs' gas-bearing properties. To address these challenges, this study investigated the No. 8 coal seam of the Benxi Formation in the Mizhi area, Ordos Basin. Accordingly, a method with the prediction of gas-bearing properties as the primary controlling factor was developed for the seismic prediction and comprehensive evaluation of CBM sweet spots. Methods First, the actual …
Evaluation Of Deep High-Quality Reservoirs Based On The Fuzzy Analytic Hierarchy Process And The Entropy Weight Method: A Case Study Of The No. 8 Coal Seam In The East-Central Ordos Basin, Yan Ronghui, Xu Hao, Hu Jianling, Li Xiaotian, Jiao Pengshuai, Huang Daojun, Chen Shida, Wu Xiaozhuo
Evaluation Of Deep High-Quality Reservoirs Based On The Fuzzy Analytic Hierarchy Process And The Entropy Weight Method: A Case Study Of The No. 8 Coal Seam In The East-Central Ordos Basin, Yan Ronghui, Xu Hao, Hu Jianling, Li Xiaotian, Jiao Pengshuai, Huang Daojun, Chen Shida, Wu Xiaozhuo
Coal Geology & Exploration
Objective Significant breakthroughs have been achieved in the exploration and exploitation of coalbed methane (CBM) in the deep No. 8 coal seam within the east-central Ordos Basin. However, a comprehensive quantitative evaluation system at the regional scale is yet to be established for reservoirs in the No. 8 coal seam. Methods Based on logs, coal quality, and measured physical property data from over 270 wells in the east-central Ordos Basin, this study developed a comprehensive evaluation system for deep coal reservoirs using the fuzzy analytic hierarchy process combined with the entropy weight method. Specifically, the evaluation system consisted of nine …
Helium Origin And Primary Factors Controlling Helium Enrichment For Bauxite Gas Reservoirs In The Longdong Area, Ordos Basin, Chen Keyu, Wang Xiaofeng, Liu Wenhui, Zhang Dongdong, Li Xiaofu
Helium Origin And Primary Factors Controlling Helium Enrichment For Bauxite Gas Reservoirs In The Longdong Area, Ordos Basin, Chen Keyu, Wang Xiaofeng, Liu Wenhui, Zhang Dongdong, Li Xiaofu
Coal Geology & Exploration
Objective Significant breakthroughs have been achieved in the exploration of bauxite gas reservoirs in the Taiyuan Formation, Longdong area, Ordos Basin. Bauxites are generally considered to hold great helium generation potential due to their relatively high uranium (U) and thorium (Th) contents. However, there remains a lack of quantitative studies on their actual contribution to helium abundance in natural gas in the area. Methods To determine dominant helium source rocks and mechanisms behind helium enrichment, this study investigated the bauxite gas reservoirs within the Taiyuan Formation in the Longdong area. Through analyses of the composition, carbon isotopes, and noble gas …
Philosophy And Methodology For Predicting Deep Coal Resources: A Case Study Of The Carboniferous-Permian Strata In The Ordos Basin, Cao Daiyong, Wei Yingchun, Ning Shuzheng, Wang Xin, Zhu Wenhao, Li Jingqi, Wang Anmin, Qiao Junwei, Xu Xiaotao, Hou Yuehua
Philosophy And Methodology For Predicting Deep Coal Resources: A Case Study Of The Carboniferous-Permian Strata In The Ordos Basin, Cao Daiyong, Wei Yingchun, Ning Shuzheng, Wang Xin, Zhu Wenhao, Li Jingqi, Wang Anmin, Qiao Junwei, Xu Xiaotao, Hou Yuehua
Coal Geology & Exploration
Objective In China, deep coal resources hold considerable potential, exhibiting promising prospects for exploitation and utilization. Therefore, gaining a clear understanding of deep coal resources provides a prerequisite and foundation for both the national strategic planning of coal resources and the scientific development and utilization of deep coal resources. Research Thinking From the perspective of the current situation of coal resources in China, this study determined the occurrence characteristics and categories of deep coal resources. Accordingly, it proposed a philosophy and workflow for predicting the resources, followed by the prediction of deep coal resources in the Carboniferous-Permian strata of the …
Advances And Prospects Of Design Optimization Technologies For Differential Development With Three-Dimensional Well Patterns For Deep Coalbed Methane Reservoirs: A Case Study Of The No. 8 Coal Seam In The Ordos Basin, Yan Xia, Fang Jianlong, Mou Chun, Meng Peilong, Wang Yuan, Yu Xiang, Fei Shixiang, Feng Yanqing, Zhao Longmei, Li Meng, Cui Yuehua, Chi Runlong, Yang Qing, Huang Li, Zheng Xiaopeng, Yin Zesong, Wang Congcong, Ma Limin, Zhang Shuang, Liu Shirui, Zhang Yang, Guo Jiali
Advances And Prospects Of Design Optimization Technologies For Differential Development With Three-Dimensional Well Patterns For Deep Coalbed Methane Reservoirs: A Case Study Of The No. 8 Coal Seam In The Ordos Basin, Yan Xia, Fang Jianlong, Mou Chun, Meng Peilong, Wang Yuan, Yu Xiang, Fei Shixiang, Feng Yanqing, Zhao Longmei, Li Meng, Cui Yuehua, Chi Runlong, Yang Qing, Huang Li, Zheng Xiaopeng, Yin Zesong, Wang Congcong, Ma Limin, Zhang Shuang, Liu Shirui, Zhang Yang, Guo Jiali
Coal Geology & Exploration
Objective Design optimization for gas reservoir development serves as a key approach to the efficient exploitation, enhanced primary recovery, and elevated efficiency with reduced costs of deep coalbed methane (CBM). Methods In this study, the most extensively developed Ordos Basin in China was investigated as an example to explore the significant heterogeneity of the geological conditions of deep coal seams. Based on a fine-scale geological investigation of over 3 000 wells across the basin, this study systematically revealed the heterogeneity of the key parameters of deep coal reservoirs, including reservoir distribution, reservoir-cap rock assemblages, coal seam structure, and gas-bearing properties. …
Sedimentary Evidence For The Connection Between The Southern Margin Of The Ordos Basin And The Paleotethys Ocean During The Permian To Early Triassic, Li Zonglin, Shi Yongsheng, Li Wenhou, Chen Long, Sun Jiaopeng
Sedimentary Evidence For The Connection Between The Southern Margin Of The Ordos Basin And The Paleotethys Ocean During The Permian To Early Triassic, Li Zonglin, Shi Yongsheng, Li Wenhou, Chen Long, Sun Jiaopeng
Coal Geology & Exploration
Objective Understanding the Permian-Early Triassic sedimentary environments along the southern margin of the Ordos Basin (also referred to as the SMOB) and their tectono-sedimentary responses to the Paleotethys Ocean plays a key role in determining the paleogeographic evolution and energy resource potential of the southern margin of the North China Craton. Methods This study investigated the Qinling Orogenic Belt (QOB) and the SMOB. Through systematic sedimentological examination based on drilling data and outcrop sections, along with a systematic review of existing paleontological findings, this study re-determined the Permian-Early Triassic tectono-paleogeographic frameworks along the SMOB. Furthermore, this study explored the paleogeography …
Supersaturation Effect And Its Characterization In Gas-Rich Intervals Of Deep Coal Seams, Zhou Lihong, Li Yong, Ding Rong, Li Yun, Li Yongzhou, Kong Jintao
Supersaturation Effect And Its Characterization In Gas-Rich Intervals Of Deep Coal Seams, Zhou Lihong, Li Yong, Ding Rong, Li Yun, Li Yongzhou, Kong Jintao
Coal Geology & Exploration
Objective and Method High free gas content serves as a key factor controlling the enrichment and high productivity of deep coalbed methane (CBM). However, its direct determination is challenging, making the accurate identification of free gas-rich coal seam intervals a core scientific issue for efficient exploration and recovery of CBM. This study investigated the Daning-Jixian block (also referred to as the Daji Block) within the Ordos Basin. Based on analyses and tests of the gas content, coal macrolithotype, physical properties, and log responses of cores collected from representative wells through pressure-retained coring, this study systematically assessed the vertical heterogeneity of …
Enrichment Factors And Play Fairway Mapping Of Helium In Typical Zones Of The Ordos Basin, Gao Jianrong, Tao Shizhen, Liu Xiangbai, Yang Wei, Zhao Zhenyu, Chen Xiuyan, Xu Wanglin, Zhang Chunlin, Song Wei, Chen Yue, Huang Junping, Ma Zhanrong
Enrichment Factors And Play Fairway Mapping Of Helium In Typical Zones Of The Ordos Basin, Gao Jianrong, Tao Shizhen, Liu Xiangbai, Yang Wei, Zhao Zhenyu, Chen Xiuyan, Xu Wanglin, Zhang Chunlin, Song Wei, Chen Yue, Huang Junping, Ma Zhanrong
Coal Geology & Exploration
Background The Ordos Basin enjoys abundant natural gas resources, which generally bear helium, making this basin hold great helium resource potential. In this case, detailed exploration is essential for the future transition from natural gas-helium joint exploration to special helium exploration in the basin.Objective and Method To systematically investigate the distribution and potential of helium resources in the Ordos Basin, natural gas samples were taken from different areas of the basin for analysis and tests. To examine the primary factors controlling helium accumulation and enrichment, this study conducted a systematic analysis of the basement, sedimentary rock layers, fault systems, …
Diagnosis, Prevention, And Control Of Liquid Accumulation In Horizontal Wellbores For Deep Coalbed Methane: A Case Study Of The Daning-Jixian Block Along The Eastern Margin Of The Ordos Basin, Zeng Wenting, Wang Zhiming, Zhang Lei, Tian Zhida, Zhen Huaibin, Dai Anna, Zeng Quanshu, Sui Tianyang
Diagnosis, Prevention, And Control Of Liquid Accumulation In Horizontal Wellbores For Deep Coalbed Methane: A Case Study Of The Daning-Jixian Block Along The Eastern Margin Of The Ordos Basin, Zeng Wenting, Wang Zhiming, Zhang Lei, Tian Zhida, Zhen Huaibin, Dai Anna, Zeng Quanshu, Sui Tianyang
Coal Geology & Exploration
Objective The Daning-Jixian block on the eastern margin of the Ordos Basin has achieved large-scale production of deep coalbed methane (CBM), with nearly 150 horizontal wells having been put into production. However, with a gradual decrease in formation energy during CBM production, gas wells exhibit declining liquid-carrying capacity. Consequently, liquid accumulation in wellbores has become a major factor affecting deep CBM production. Recovery of deep CBM shows the coexistence of free and desorbed gases, accompanied by significantly varying gas/liquid ratios. Moreover, gas production channels and techniques vary in different production stages. Hence, there is an urgent need to develop a …
Suitability Evaluation For Deep Geological Storage Of Mine Water In The Ordos Basin, Gulbostan Tursun, Sui Wanghua, Aibibai Mamat, Yang Weifeng, Chen Ge, Gao Liang
Suitability Evaluation For Deep Geological Storage Of Mine Water In The Ordos Basin, Gulbostan Tursun, Sui Wanghua, Aibibai Mamat, Yang Weifeng, Chen Ge, Gao Liang
Coal Geology & Exploration
Objective Given the issues of large mine water drainage in coal mines in China, as well as the corresponding high treatment cost and low utilization rate, thoroughly investigating efficient, environmentally friendly, economically feasible mine water treatment technologies is the key to the green transformation and the implementation of the sustainable development strategy in the coal industry. Deep geological storage of mine water represents an emerging technology for mine water treatment, enjoying the advantages of low cost and zero emissions. A key step in the application of this technology is to select suitable target reservoirs. Although relevant studies have proposed some …
Trace Element Migration In Groundwater In Sandstone Aquifers In The Jurassic Coalfields: A Case Study Of The Guojiahe Coal Mine, Shi Longqing, Qu Xingyue, Cheng Hao
Trace Element Migration In Groundwater In Sandstone Aquifers In The Jurassic Coalfields: A Case Study Of The Guojiahe Coal Mine, Shi Longqing, Qu Xingyue, Cheng Hao
Coal Geology & Exploration
Background The Ordos Basin, a vital energy hub in China, contains considerable coal reserves. However, the environmental issues arising from coal mining warrant attention, especially given the fragile ecosystems of the Jurassic coalfields. Methods This study investigated the Guojiahe Coal Mine in Shaanxi Province. Based on measured concentrations of 31 trace elements dissolved in sandstone aquifers across varying geological ages, this study conducted a comparative analysis of the evolutionary characteristics of these trace elements between unmined reducing and post-mining oxidizing conditions using numerical simulations. Accordingly, it revealed the impacts of coal seam mining on trace element migration in groundwater in …
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 …
Application Of Five Seismic Attributes In Natural Fracture Prediction For Deep Coalbed Methane Production Along The Eastern Margin Of The Ordos Basin, Tong Jiangnan, Wang Feng, Zhang Feng, Hou Wei, Li Zhongbai, Ji Liang, Jiang Yanan, Sun Wei
Application Of Five Seismic Attributes In Natural Fracture Prediction For Deep Coalbed Methane Production Along The Eastern Margin Of The Ordos Basin, Tong Jiangnan, Wang Feng, Zhang Feng, Hou Wei, Li Zhongbai, Ji Liang, Jiang Yanan, Sun Wei
Coal Geology & Exploration
Background Natural fractures serve as both the primary storage space for free gas of deep coalbed methane (CBM) and pathways for hydrocarbon migration. Furthermore, these fractures can enhance the porosity and permeability of strata under the deep, high-pressure condition, significantly amplifying the permeability of coal seams. Therefore, the fine-scale characterization of the planar distribution of natural fractures is crucial to deep CBM production.Objectives and Methods This study investigated the No.8 coal seam in the Carboniferous Benxi Formation within the Daning-Jixian block on the eastern margin of the Ordos Basin. Through offset vector tiles (OVT) domain processing of offshore 3D …
Geological Characteristics And Key Technologies For Exploration And Development Of The Yanchuannan Coalbed Methane Field, Ordos Basin, He Xipeng, Xiao Cui, Gao Yuqiao, Li Xin, Guo Tao, Cai Xiao
Geological Characteristics And Key Technologies For Exploration And Development Of The Yanchuannan Coalbed Methane Field, Ordos Basin, He Xipeng, Xiao Cui, Gao Yuqiao, Li Xin, Guo Tao, Cai Xiao
Coal Geology & Exploration
Objective China boasts abundant coalbed methane (CBM) resources, which serve as a crucial replacement for the reserve growth and production addition of natural gas resources. In recent years, CBM exploration and production have gradually expanded into deep, thin coal seams, which, however, are characterized by strong heterogeneity, ultra-low permeability, high in situ stress, and complex enrichment patterns. Therefore, the exploration and exploitation of deep, thin coal seams face challenges such as inadequate geological theories, poor adaptability of key technologies, and low investment returns, which hinder large-scale commercial CBM production. Methods Focusing on the exploration and exploitation practice of middle-deep, thin …
China’S Cbm Exploration And Production And Associated Technological Advancements: A Review And Reflections, Ye Jianping
China’S Cbm Exploration And Production And Associated Technological Advancements: A Review And Reflections, Ye Jianping
Coal Geology & Exploration
Objective and Methods Based on extensive scientific and technical literature and technical data on coalbed methane (CBM) exploration and production projects, this study conducted a comparative analysis of the development process and latest advances in China’s critical technologies for CBM exploration and production and reviewed the CBM exploration and production history of this country over the past three decades. Accordingly, this study discussed the theoretical and technical challenges in CBM exploration and production and proposed future development directions. Advances The results indicate that the insights into conversion between adsorbed and free deep CBM prove to be a significant theoretical understanding. …
Accumulation Mechanisms And Resource Potential Of Helium In Coal Measures: A Case Study Of The Eastern Margin Of The Ordos Basin, Liu Xiangbai, Tao Shizhen, Yang Xiuchun, Zhao Qun, Chen Yanyan, Liu Ziyang, Pei Xiangbing, Wang Longfei, Yi Wei, Feng Jianqiu, Zhang Tan, Gao Jianrong, Tao Xiaowan, Liu Zhuangxiaoxue, Li Chaozheng, Yang Yiqing, Chen Yue
Accumulation Mechanisms And Resource Potential Of Helium In Coal Measures: A Case Study Of The Eastern Margin Of The Ordos Basin, Liu Xiangbai, Tao Shizhen, Yang Xiuchun, Zhao Qun, Chen Yanyan, Liu Ziyang, Pei Xiangbing, Wang Longfei, Yi Wei, Feng Jianqiu, Zhang Tan, Gao Jianrong, Tao Xiaowan, Liu Zhuangxiaoxue, Li Chaozheng, Yang Yiqing, Chen Yue
Coal Geology & Exploration
Background Helium, with advantages such as stable chemical properties and high thermal conductivity, has been extensively applied in high-tech sectors like national defense, military, aviation, and aerospace, playing an irreplaceable role. Presently, helium in China is primarily imported from other countries, manifesting a high degree of dependence on foreign trade, suggesting a prominent issue concerning helium resource security. Previous studies on helium principally focus on conventional natural gas, rendering helium in coal measures relatively under-studied. Objective and Methods To determine the distribution and potential of helium resources in coal measures, this study analyzed the coal-measure gas sampled from the eastern …
Discovery Of A Large Gas Field Of Deep Coalbed Methane In The Shenfu Block And Its Implications, Zhu Guanghui, Ji Hongquan, Mi Honggang, Zhang Yingchun, Sun Qiang, Zhao Wei, Zhu Xueshen, Kang Lifang, Wang Yuchuan
Discovery Of A Large Gas Field Of Deep Coalbed Methane In The Shenfu Block And Its Implications, Zhu Guanghui, Ji Hongquan, Mi Honggang, Zhang Yingchun, Sun Qiang, Zhao Wei, Zhu Xueshen, Kang Lifang, Wang Yuchuan
Coal Geology & Exploration
Background After explorations of unconventional natural gas for nearly two decades in the Shenfu block on the eastern margin of the Ordos Basin, deep coalbed methane (CBM) with reserves of 100 billion m3 was discovered in this block in 2023. However, the preliminary exploration of deep CBM in this block faces challenges of insufficient understanding of geological laws, immature fracturing technologies, and a lack of production technologies and experience.Methods and Results Driven by both management and technological innovations, encouraging exploration results have been achieved. The management innovations include: (1) The implementation of a complementary and three-dimensional exploration model …
Characteristics And Transformations Of Mineral Phases In Burnt Rocks, Yalikun Rexiti, Huang Lei, Yang Fan, Xue Xiaoyuan, Song Shijun, Hu Jian, Zhang Zeyu, Ji Zhongkui
Characteristics And Transformations Of Mineral Phases In Burnt Rocks, Yalikun Rexiti, Huang Lei, Yang Fan, Xue Xiaoyuan, Song Shijun, Hu Jian, Zhang Zeyu, Ji Zhongkui
Coal Geology & Exploration
Objective Burnt rocks are special rocks formed by the surrounding rocks that are baked due to the spontaneous combustion of coal seams. They are extensively distributed in the Yan’an Formation on the northeastern margin of the Ordos Basin. However, the characteristics and formation mechanisms of burning-associated mineral phases in these rocks remain unclear. Methods This study conducted analytical tests and high-temperature heating simulations of protolith to analyze the mineral phases of underground burnt rocks in the Zhangjiamao Coal Mine, Shaanxi Province. Results and Conclusions The results indicate that the underground burnt rocks exhibit enrichment in mafic components, abnormal migration of …
Identification Of Tar-Rich Coal Based On The True Density And Natural Gamma Ray Response Of Coals, Shi Qingmin, Geng Xuhu, Wang Shuangming, Cai Yue, Han Bo, Wang Shengquan, Zhang Zhehao, He Yufei
Identification Of Tar-Rich Coal Based On The True Density And Natural Gamma Ray Response Of Coals, Shi Qingmin, Geng Xuhu, Wang Shuangming, Cai Yue, Han Bo, Wang Shengquan, Zhang Zhehao, He Yufei
Coal Geology & Exploration
Objective Tar yield, derived from the Gray-King assay, serves as the sole metric for evaluating tar-rich coal. However, insufficient exploration data hinder its effective application in the fine-scale evaluation of extensive tar-rich coal. Methods Based on binary classification, this study proposed the optimal thresholds for tar-rich coal identification using true density (ρ) and natural gamma-ray (GR) log. Moreover, this study elucidated the intrinsic mechanisms behind the significant petrophysical parameter responses of tar-rich coal. Results and Conclusions Key findings are as follows: (1) Coals with various metamorphic grades differ in identification threshold. For instance, long-flame tar-rich coal, the optimal …
Deep Coalbed Methane Production Technology For The Eastern Margin Of The Ordos Basin: Advances And Their Implications, Zeng Wenting, Xu Fengyin, Zhang Lei, Sun Weiwei, Wang Qian, Liu Yinhua, Yu Lizhu, Ji Liang, Zeng Quanshu, Zhang Kang
Deep Coalbed Methane Production Technology For The Eastern Margin Of The Ordos Basin: Advances And Their Implications, Zeng Wenting, Xu Fengyin, Zhang Lei, Sun Weiwei, Wang Qian, Liu Yinhua, Yu Lizhu, Ji Liang, Zeng Quanshu, Zhang Kang
Coal Geology & Exploration
Contrasting with shallow to moderately deep coalbed methane (CBM) reservoirs, deep CBM reservoirs exhibit favorable coal structures, high formation pressure, high free gas ratios, and high contents of total dissolved solids (TDS) and CO2. Extensive fracturing allows for CBM flowing at the initial stage, while the production parameters vary significantly throughout the CBM production. This requires wide technological boundaries of the main production technologies. Compared to shale gas and tight gas, deep CBM manifests different production mechanisms and relatively low free gas ratios, which lead to short flowing cycles of CBM. This necessitates timely water withdrawal for CBM …
Numerical Simulations Of The Effects Of Bedding Planes On Hydraulic Fracture Propagation Law In Oil Shale, Li Yanwei, Zhu Chaofan, Zeng Yijian, Shui Haoche, Fan Cunhan, Guo Wei
Numerical Simulations Of The Effects Of Bedding Planes On Hydraulic Fracture Propagation Law In Oil Shale, Li Yanwei, Zhu Chaofan, Zeng Yijian, Shui Haoche, Fan Cunhan, Guo Wei
Coal Geology & Exploration
Hydraulic fracturing serves as a major technical means for the exploitation of oil shale reservoirs presently, and the hydraulic fracture morphology in oil shales is primarily affected by differences in the characteristics of bedding planes. However, current studies mostly focus on the influence of the developmental degree of bedding planes on fracture propagation, overlooking the effects of the bedding plane thickness itself on hydraulic fracture propagation. This study delves into the oil shale in the Xunyi area, Ordos Basin. Based on the theory of linear elastic fracture mechanics, this study developed a stress-damage-seepage model of hydraulic fracture propagation. Using the …
Application And Improvement Directions Of Rodless Drainage Technology In Coalbed Methane Wells: A Case Study From East Margin Of Ordos Basin, Ma Wentao, Liu Yinhua, Wu Jianjun, Wang Yubin, Wang Chengwang, Xu Wanyong
Application And Improvement Directions Of Rodless Drainage Technology In Coalbed Methane Wells: A Case Study From East Margin Of Ordos Basin, Ma Wentao, Liu Yinhua, Wu Jianjun, Wang Yubin, Wang Chengwang, Xu Wanyong
Coal Geology & Exploration
The eastern margin of Ordos Basin has a huge amount of coalbed methane resources, and has become one of the main coalbed methane producing areas in China. Since the development of the block, hydraulic rodless pump, hydraulic jet pump, electric submersible pump and diaphragm pump drainage and production process tests have been carried out for highly deviated wells and horizontal wells in medium shallow coal seam. During production, it is found that the above four types of rodless drainage and production processes have the advantages of effectively avoiding eccentric wear of pipes and rods in highly deviated wells and horizontal …
Preliminary Investigation Of Uranium Resource Evaluation Method Based On Natural Gamma Logging Data：A Case Study Of The Pengyang Uranium Deposit In Ordos Basin, Yu Reng’An, Sun Dapeng, Zhou Xiaoxi, Deng Fan, Si Qinghong, Hu Yongxing
Preliminary Investigation Of Uranium Resource Evaluation Method Based On Natural Gamma Logging Data：A Case Study Of The Pengyang Uranium Deposit In Ordos Basin, Yu Reng’An, Sun Dapeng, Zhou Xiaoxi, Deng Fan, Si Qinghong, Hu Yongxing
Coal Geology & Exploration
“Coal and uranium exploration” and “oil and uranium exploration” are current research hotspots. Using logging data of coal and oilfield drilling to further evaluate uranium resources remains a difficult problem. Taking the Pengyang uranium deposit in the Ordos Basin as an example, this article explores the method of evaluating uranium resources based on natural gamma logging data. According to the remarkable features of the natural gamma anomaly response in the sandstone-type uranium reservoirs in the study area, the natural gamma logging regression model of the quantitative gamma logging value of the uranium deposit in the Pengyang area was studied by …
Progress Of Coalbed Methane Exploration And Development In China During The 13th Five-Year Plan Period And The Next Exploration Direction, Ye Jianping, Hou Songyi, Zhang Shouren
Progress Of Coalbed Methane Exploration And Development In China During The 13th Five-Year Plan Period And The Next Exploration Direction, Ye Jianping, Hou Songyi, Zhang Shouren
Coal Geology & Exploration
Based on survey data of coalbed methane exploration and development projects in China, the production status of coalbed methane fields and scientific & technological achievements, this paper analyzes the comprehensive control technical measures for stable and increasing production of coalbed methane fields, and the geological conditions and potential of deep coalbed methane exploration breakthrough. The coalbed methane horizontal well technology and the matching well pattern optimization and drainage technology are also summarized. The results show that the most effective technical measures for the comprehensive control of stable production of coalbed methane fields and low production wells in China are four …
Multi-Scale Prediction Of Coal Seam Fracture Development In Mg Block, Eastern Margin Of Ordos Basin, Zhu Guanghui, Li Zhongcheng, Shi Suzhen, Shi Hao, Lin Liming, Liu Yancheng, Zhang Xin
Multi-Scale Prediction Of Coal Seam Fracture Development In Mg Block, Eastern Margin Of Ordos Basin, Zhu Guanghui, Li Zhongcheng, Shi Suzhen, Shi Hao, Lin Liming, Liu Yancheng, Zhang Xin
Coal Geology & Exploration
Finding out the development characteristics of coal seam fractures is of great significance for coalbed methane exploitation and safe production of underground coal mines. Logging and seismic are effective means of geophysical identification of coal seam fractures. Electrical imaging, resistivity, density, sonic differential time, natural gamma, neutron porosity and array acoustic logs are used to describe the small scale fracture morphology of No.8 and No.9 coal seams of MG block in the eastern margin of Ordos Basin. The middle-scale fracture of No.8 and No.9 coal seams was predicted by prestack Azimuth AVO inversion in OVT domain. And the large-scale fracture …
Geological Characteristics And Reservoir-Forming Potential Of Shale Gas Of Transitional Facies In Linxing Area, Eastern Margin Of Ordos Basin, Wu Peng, Cao Di, Zhu Guanghui, Liu Xueqing, Li Yong, Li Yangbing, Hu Weiqiang, Liu Zaizhen, Kong Wei, Fei Jingliang
Geological Characteristics And Reservoir-Forming Potential Of Shale Gas Of Transitional Facies In Linxing Area, Eastern Margin Of Ordos Basin, Wu Peng, Cao Di, Zhu Guanghui, Liu Xueqing, Li Yong, Li Yangbing, Hu Weiqiang, Liu Zaizhen, Kong Wei, Fei Jingliang
Coal Geology & Exploration
Shale gas of transitional facies is the important replacing area for increase of shale gas reserves and production. On the basis of the experiment and research data of shale of transitional facies of Linxing area in the eastern margin of Ordos Basin, by selecting the strata series of Shanxi Formation, Taiyuan Formation and Benxi Formation as the research object, from the sedimentary environments, shale distribution, organic geochemical characteristics, mineralogy, physical characteristics and gas-bearing characteristics, etc., the geology characteristics of the shale gas transitional facies in the study area were summarized and dissected systematically to analyze its enrichment and reservoir-forming potential. …
Medium Characteristics And Hydrodynamic Evolution Law Of High Salinity Mine Water Recharge In Deep Well, Liu Qi, Wang Weijun, Luo Bin, Wang Houzhu, Zhang Zhijun
Medium Characteristics And Hydrodynamic Evolution Law Of High Salinity Mine Water Recharge In Deep Well, Liu Qi, Wang Weijun, Luo Bin, Wang Houzhu, Zhang Zhijun
Coal Geology & Exploration
The treatment and discharge of high salt mine water is one of the important factors affecting efficient coal mining in recent years. It is a worth exploring method to reduce the discharge of mine water by selecting the appropriate aquifer under the floor of the coal seam and transferring the high salt mine water to other places. Taking the X mine in the Ordos Basin as an example, the Baotashan sandstone and the deep Liujiagou Formation sandstone formation below the coal seam have transfer storage space. By mercury intrusion experiment and rock mechanics analysis, the two groups of formations were …