A Calculational Model For 3d Fault Complexity Based On Curvature Analysis And Fractal Dimensions,
2024
CCTEG China Coal Research Institute, Beijing 100013, China; CCTEG Xi’an Transparent Geology Technology Co., Ltd., Xi’an 712000, China; CCTEG Xi’an Research Institute (Group) Co., Ltd., Xi’an 710077, China; National Key Laboratory of Intelligent Coal Mining and Rock Stratum Control, Beijing 100013, China
A Calculational Model For 3d Fault Complexity Based On Curvature Analysis And Fractal Dimensions, Yan Junsheng, Liu Zaibin, Fan Tao, Yang Hui, Liu Wenming, Du Wengang, An Lin, Liu Chenguang, Wang Xiaohui
Coal Geology & Exploration
Objective and Methods Faults are identified as one of the most threatening geological structural factors among hidden disaster-causing factors in coal mines. However, the 3D quantitative assessment of them remains challenging. Considering that existing quantitative indicators fail to fully reflect fault morphologies and there is a lack of 3D methods, this study proposed a calculational model for 3D fault complexity based on curvature analysis and fractal dimensions. This model improved the morphologies of traditional measurement volumes of fractal dimensions by employing the Delaunay tetrahedralization algorithm, thus effectively reducing the invalid values in calculating the 3D fractal dimensions of faults. Moreover, …
Exploration Of The Impacts Of Cement Sheath On Casing Stress Based On The Arching Effects Of Formations,
2024
College of Safety and Ocean Engineering, China University of Petroleum (Beijing), Beijing 102249, China
Exploration Of The Impacts Of Cement Sheath On Casing Stress Based On The Arching Effects Of Formations, An Fengchen, Miao Zhibo, Meng Siwei, Wei Ziying, Zhang Xiao, Zeng Jiaming, Wang Xiaohua
Coal Geology & Exploration
Objective With the growth in the demand for natural oil and gas and the technological progress of their production, the oil and gas well depths have been constantly setting new records. The increase in the depth corresponds to sharply increasing in-situ stress, leading to increasingly severe damage to the casing of ultradeep oil and gas wells. To enhance the bearing capacity of the casing under high in-situ stress, high-strength casing with a large wall thickness is typically employed, a measure which has been proved, however, less effective. Methods This study established a finite element model of the casing-cement sheath-formation system …
Commingling Production Of Deep Coal-Measure Gas Through Hydraulic Fracturing: Propagation Patterns Of Induced Fractures And Their Determinants,
2024
School of Geological Engineering, Qinghai University, Xining 810016, China
Commingling Production Of Deep Coal-Measure Gas Through Hydraulic Fracturing: Propagation Patterns Of Induced Fractures And Their Determinants, Chen Hao, Li Guozhang, Qin Yong, Wang Jianguo, Shen Jian, Sun Yuqi, Yuan Erjun, Li Dian
Coal Geology & Exploration
Objective The commingling production of coal-measure gas represents a pivotal approach to enhancing the single-well production of unconventional gas in China. However, coal-measure gas reservoirs exhibit distinctly different material compositions and physical properties, leading to uncertainty of the propagation modes and developmental degrees of fractures in different reservoirs during the hydraulic fracturing of coal-measure gas reservoirs subjected to commingling production. Therefore, effectively coordinating the stimulation of multiple reservoirs for multi-gas commingling production is crucial for minimizing production costs and maximizing production capacity. Methods This study investigated the Linxing block along the northeastern margin of the Ordos Basin as an example …
Application Of D-Insar In Monitoring The Impacts Of Shaft Grouting On Surface And Building Deformations,
2024
School of Resources and Environmental Engineering, Anhui University, Hefei 230601, China; Anhui Province Engineering Laboratory for Mine Ecological Remediation, Hefei 230601, China
Application Of D-Insar In Monitoring The Impacts Of Shaft Grouting On Surface And Building Deformations, Liu Hui, Lu Rumeng, Su Lijuan, Cheng Shiguang, Zhang Pengfei, Cheng Hua
Coal Geology & Exploration
Objective In coal mining engineering, damaged well walls pose a threat to the safety of production facilities and mines. Comprehensively monitoring the impacts of shaft grouting on the deformations of mine surface plants and surface buildings is critical for ensuring the safe production of mines. Methods This study investigated a coal mine in the mining area within northern Anhui Province. Using the 15 scenes of Sentinel-1A image data covering the coal mine and the differential interferometric synthetic aperture radar (D-InSAR) technology, this study comprehensively monitored the subsidence of mine surface plants and surface buildings before and after shaft grouting, obtaining …
Fracture Structure Of The Overburden In The Layered Mining Of Extremely Thick Coal Seams: Developmental Patterns Of Caving Zones And Hydraulically Conductive Fracture Zones And Fracture Characteristics,
2024
Shandong Energy Group South America Co., Ltd., Qingdao 266000, China
Fracture Structure Of The Overburden In The Layered Mining Of Extremely Thick Coal Seams: Developmental Patterns Of Caving Zones And Hydraulically Conductive Fracture Zones And Fracture Characteristics, Zhang Xin, Chen Youkuo, Meng Hailun, Qin Qifa, Cheng Xianggang, Huang Rongjie, Dong Hairui, Sun Wenbin, Qiao Wei
Coal Geology & Exploration
Objective The Zhunnan Coalfield, a coalfield on the southern margin of the Junggar Basin in Xinjiang, boasts abundant coal resources. However, water hazards in mines severely constrain the safe and efficient coal production in the coalfield. Since hydraulically conductive fractures in roofs serve as primary hydraulically conductive channels formed in the mining of the mining face, it is particularly crucial to investigate the developmental patterns of these fractures during the layered mining of extremely thick coal seams. Methods This study explored the (9-15)08 mining face of the Liuhuanggou Coal Mine in Xinjiang. Using ground exploration holes and borehole televiewers, this …
Hydrochemical Characteristics And Component Sources Of Water In Underground Reservoirs In The Daliuta Coal Mine,
2024
State Key Laboratory of Water Resource Protection and Utilization in Coal Mining, Beijing 102211, China; School of Earth and Environment, Anhui University of Science and Technology, Huainan 232001, China
Hydrochemical Characteristics And Component Sources Of Water In Underground Reservoirs In The Daliuta Coal Mine, Zhang Haitao, Jiang Binbin, Zhang Haiqin, Li Peng, Wu Min, Hao Jingwei, Hu Yutian
Coal Geology & Exploration
Objective Underground reservoirs in coal mines are capable of storing and purifying mine water. A deep understanding of the hydrochemical characteristics and formation mechanisms of water in underground reservoirs is identified as an important prerequisite for large-scale development of technologies for mine water treatment. Methods This study investigated the underground reservoirs in the Daliuta Coal Mine within the Shendong area by testing and analyzing their influent and effluent water samples. Using methods such as the ion ratio method, multivariate statistical analyses (e.g., correlation analysis and principal component analysis (PCA)), and the positive matrix factorization (PMF) model, this study delved into …
Microscopic Fracture Characterization And Permeability Evolutionary Patterns Of Granites Under Cyclic Thermal Shock,
2024
State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; School of Resources and Safety Engineering, Chongqing University, Chongqing 400044, China
Microscopic Fracture Characterization And Permeability Evolutionary Patterns Of Granites Under Cyclic Thermal Shock, He Jiangfu, Ren Chengcheng, He Kun, Yu Qihang, Li Xinru, Deng Xu
Coal Geology & Exploration
Objective This study aims to reveal the microscopic damage characteristics and permeability evolutionary patterns of high-temperature granite reservoirs fractured under cyclic thermal shock produced by low-temperature fluids like drilling fluids and circulating heat recovery media in the exploitation process of the enhanced geothermal systems (EGSs). Methods Using experiments on the fracturing characteristics of high-temperature granites under the conditions of varying cooling methods, numbers of thermal shock cycles, and cooling temperatures, this study determined microstructural characteristic parameters such as compressional wave (P-wave) velocity, pore volumetric fraction, and fractal dimension of granites across a temperature range of 25 to 700 ℃ under …
An Integrated Ecosystem Monitoring Technology For Coal Mining Subsidence Areas And Its Application In The Shendong Mining Area,
2024
CHN Shendong Coal Group Co., Ltd., Yulin 719315, China
An Integrated Ecosystem Monitoring Technology For Coal Mining Subsidence Areas And Its Application In The Shendong Mining Area, Cheng Yang, Liu Wei, Zhang Na, Li Guanjie, Liu Kai, Zhang Chengye, Li Jun
Coal Geology & Exploration
Background The ecosystem monitoring of arid and semi-arid coal mining subsidence areas acts as a significant prerequisite for regional ecosystem conservation and management, holding critical significance for accelerating green mine construction. Methods Based on the Chinese government's regulatory requirements for mine ecosystems, this study analyzed the difficulties in ecosystem monitoring in the coal mining subsidence area of the Shendong mining area (also referred to as the Shendong coal mining subsidence area). By detailing the integrated coal-rock-water-soil-air-vegetation-carbon monitoring technology system, this study determined the factors, principal methods, and technology roadmap for the integrated ecosystem monitoring in the Shendong coal mining subsidence …
Identifying The Lithologies And Thicknesses Of Coal Seam Roofs And Floors Based On Multiparameter Logging Of Boreholes,
2024
State Key Laboratory Cultivation Base for Gas Geology and Gas Control, Henan Polytechnic University, Jiaozuo 454003, China; College of Safety Science and Engineering, Henan Polytechnic University, Jiaozuo 454003, China
Identifying The Lithologies And Thicknesses Of Coal Seam Roofs And Floors Based On Multiparameter Logging Of Boreholes, Li Zhe, Gao Baobin, Lei Wenjie, Li Donghui, Li Zixin
Coal Geology & Exploration
Background In the process of coal mining, effective exploration methods for stratigraphic characteristics are crucial to underground operations. The reason is that the accurate stratigraphic characteristics of coal seams, along with the surrounding rocks of coal seam roofs and floors, facilitate the treatment of gas in coal seams, thereby ensuring safe and efficient coal mining. Methods Based on the multiparameter logging of boreholes crossing strata in a bottom drainage roadway, this study highlighted the lowstand, upgoing borehole trajectories, as well as the variations in parameters including natural gamma rays, spontaneous potential, and resistivity. By comprehensive comparison of the trajectories, video-derived …
Spatiotemporal Response Characteristics Of Transient Electromagnetic Field In Water-Bearing Goaves And Their Applications,
2024
College of Energy and Mining Engineering, Shandong University of Science and Technology, Qingdao 266590, China
Spatiotemporal Response Characteristics Of Transient Electromagnetic Field In Water-Bearing Goaves And Their Applications, Song Guilei, Gong Xufei, Yang Fuqiang, Cui Jianting, Li Zhanling, Liu Lina
Coal Geology & Exploration
Objective and Methods This study aims to enhance the accuracy of the mine transient electromagnetic method (MTEM) in of imaging of water-bearing goaves. Based on the geological conditions of the Gaojialiang Coal Mine, this study simulated the spatiotemporal response characteristics of the induced magnetic field in the water-bearing goaf model under varying stratigraphic spacings using finite element software COMSOL. Accordingly, this study analyzed the distribution patterns of the induced magnetic field on the apparent resistivity pseudosections and the plots of the differentials of longitudinal apparent conductivity. Using the results, the water-bearing conditions of goaves in the Ordos Gaojialiang Coal Mine …
Biomimetic Technologies For Drill Rods: Advances In Research And Development Trends,
2024
CCTEG Xi’an Research Institute (Group) Co., Ltd., Xi’an 710077, China
Biomimetic Technologies For Drill Rods: Advances In Research And Development Trends, Wang Chuanliu, Ju Pei
Coal Geology & Exploration
Significance Drill rods are recognized as core tools in drilling engineering, and their performance exerts a significant influence on drilling efficiency and safety. Over recent years, applying biomimetic technologies to drill rod design has gradually emerged as a hot research topic. By imitating the remarkable structures, morphologies, and material properties of living organisms in nature, biomimetic technologies provide entirely new philosophies and approaches for the innovative design of drill rods. Advances This study summarizes the advances in research on biomimetic technologies for drill rods in terms of the biomimetic design of structures, morphologies, and materials. Regarding the biomimetic design of …
Development Of Robotic Sampling Method For Rees In Gps-Denied And Hazardous Environments,
2024
Montana Technological University Graduate School
Development Of Robotic Sampling Method For Rees In Gps-Denied And Hazardous Environments, Alan Arthur
Graduate Theses & Non-Theses
In recent times, the demand for rare earth elements (REEs) has been fueled by industry shifts towards energy efficiency and climate neutrality, as well as the great potential for the use of REEs in all sectors of our daily lives. Currently, China accounts for over 75% of global REE production (Dal, 2024). Various REE producers are gearing up to produce significant amounts of REEs to solve the issue of global supply and break China’s monopoly. A spike in REE prices of nearly tenfold in 2011 provided the impetus for accelerating over 400 REE exploration projects around the world (Barakos, 2017). …
Optimisation Of Open Pit Slope Design Considering Groundwater Effects Using Particle Swarm Optimisation And Scaled Boundary Finite Element Method,
2024
Missouri University of Science and Technology
Optimisation Of Open Pit Slope Design Considering Groundwater Effects Using Particle Swarm Optimisation And Scaled Boundary Finite Element Method, Dakshith Ruvin Wijesinghe, Ethmadalage Perera, Ean Hin Ooi, Sundararajan Natarajan, Taghi Sherizadeh, Ean Tat Ooi
Mining Engineering Faculty Research & Creative Works
Slopes are a crucial structure in open pit mines. Their design has implications on the economic, safety and environmental operation of the mining industry. Designing stable slopes can be challenging due to the complexities introduced by the stratigraphy and hydrology of the strata. With rising commodity costs and inflation rates, mining operating costs are increasing. Reducing operational costs is necessary for mining industries to remain competitive. While steepening the pit slope can decrease stripping materials and save money, it also increases the risk associated with slope surges. Therefore, optimizing slopes is crucial for both financial and safety reasons. Numerical models …
3d Reconstruction Of Surface Temperature Field In Spontaneous Combustion Coal Gangue Dump Fire Area And Its Practice,
2024
School of Safety Engineering, China University of Mining and Technology, Xuzhou 221116, China; No.156 Coalfield Geological Exploration Brigade, Xinjiang Uygur Autonomous Region Bureau of Coal Geology, Urumqi 830009, China
3d Reconstruction Of Surface Temperature Field In Spontaneous Combustion Coal Gangue Dump Fire Area And Its Practice, Shao Zhenlu, Zhang Huisong, Deng Rong, Yang Tong, Ma Dong
Coal Geology & Exploration
Objective The spontaneous combustion of coal gangue dumps has severely damaged the ecological environment and affected the production safety, which has become a bottleneck in the process of ecological civilization construction in China. In order to formulate a fire extinguishing plan and implement a fire extinguishing project, it is very important to accurately detect the fire area of the spontaneous combustion coal gangue dump. Methods Herein, the idea of detecting the three-dimensional distribution of high-temperature areas using unmanned aerial vehicle (UAV) based thermal infrared oblique photogrammetry technology was proposed. Meanwhile, the multi-scale Gaussian filtering detail enhancement technology for thermal infrared …
Impacts And Regulation Mechanisms Of Phase-Change Wall Microspheres On Cement Slurry Performance In Well Cementing,
2024
State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu 610059, China
Impacts And Regulation Mechanisms Of Phase-Change Wall Microspheres On Cement Slurry Performance In Well Cementing, Zheng Mingming, Wu Zurui, Yan Shichun, Hu Yunpeng, He Juan, Zhang Yawei, Xiong Liang, Zhu Chengtao
Coal Geology & Exploration
Objective The current design of low-heat cement slurries prepared by adding microspheres with phase change materials as wall materials for well cementing in strata bearing natural gas hydrates (NGHs) fails to fully account for the impacts of the particle size and mass fraction of the microspheres on the performance of cement slurries. This leads to impaired cement slurry performance and increased costs, further inducing many problems with well cementing quality. Hence, it is significant to analyze the impacts and controlling mechanisms of the microspheres on cement slurry performance. Methods To eliminate the interference of the heat storage effect of the …
Design Method For Active Slope Reinforcement: A Case Study Of Excavated Slopes,
2024
State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China; School of Engineering Science, University of Chinese Academy of Sciences, Beijing 100049, China
Design Method For Active Slope Reinforcement: A Case Study Of Excavated Slopes, Qin Hui, Yin Xiaotao, Tang Hua, Cheng Xu
Coal Geology & Exploration
Objective Slope instability and failure exhibit extinct spatiotemporal characteristics. Existing design methods for passive reinforcement have resulted in the engineering instability of numerous excavated slopes. Therefore, analyzing the spatiotemporal evolutionary patterns of slopes during excavation and exploring the design methods for active slope reinforcement are particularly important for the information technology (IT)-based construction and safety control of slopes. Methods Using on-site investigations and numerical simulations, this study analyzed the causes of excavation-induced failure of high slopes, as well as the evolutionary pattern of the principal stresses in the sliding zone. Consequently, this study revealed the progressive failure mechanism of slopes …
Natural Gamma-Ray Log-Derived Heat Production Rates Of Strata And Lithospheric Thermal Structure In The Central Depression, Yinggehai Basin,
2024
College of Earth and Planetary Sciences, Chengdu University of Technology, Chengdu 610059, China
Natural Gamma-Ray Log-Derived Heat Production Rates Of Strata And Lithospheric Thermal Structure In The Central Depression, Yinggehai Basin, Zhang Jiahao, Song Rongcai, Zheng Feng, Zhang Yan, Tang Xin, Li Bo, Dong Shuyi
Coal Geology & Exploration
Objective Understanding the lithospheric thermal structure is significant for exploring the dynamics of a basin's thermal evolution, as well as for the assessment, exploitation, and utilization of geothermal resources in a basin. However, the limited data on heat production in the Yinggehai Basin has constrained research into the lithospheric thermal structure of the basin. Methods Using natural gamma-ray (NGR) logs from 23 wells in the Yinggehai Basin, this study calculated the heat production rates of strata in the central depression using the fitted gamma-ray value (GR) - radiogenic heat production rate (A) empirical formula. Based on the ocean …
Table Of Contents,
2024
China Coal Technology and Engineering Group (CCTEG)
State Of The Art And Future Directions In Groundwater Contamination Risk Assessment,
2024
College of Transportation Engineering, Nanjing Tech University, Nanjing 211816, China
State Of The Art And Future Directions In Groundwater Contamination Risk Assessment, Xu Beiyi, Wang Ce, Zhou Guangyang, Zhou Pengpeng
Coal Geology & Exploration
Background Rapid global socio-economic development has intensified the resource crisis and contamination of groundwater, rendering groundwater contamination risk assessments critical to contamination prevention, control, and remediation. Advances Through a systematic summary of domestic and international studies, this study reviews the development of theories on groundwater contamination risk assessments and the formation of the theoretical system. Based on the source-pathway-receptor assessment system, this study presents a summary of the research methods for the assessments of contamination source load risks, groundwater vulnerability, and contamination hazards. Groundwater contamination risk assessments have evolved from unidimensional qualitative assessments to quantitative process models highlighting contamination mechanisms …
Techniques For Coal Resource Conservation During The Ecological Restoration Of Alpine Mining Areas On Plateaus,
2024
College of Geology and Environment, Xi’an University of Science and Technology, Xi’an 710054, China; China Coal Aerial Photogrammetry and Remote Sensing Group Co. Ltd., Xi’an 710199, China
Techniques For Coal Resource Conservation During The Ecological Restoration Of Alpine Mining Areas On Plateaus, Li Congcong, Wang Tong, Zhao Xin, Wang Weichao, Liang Zhenxin
Coal Geology & Exploration
Objective The prolonged coal mining of the Muli coalfield, located in an alpine region in the eastern Qinghai-Tibet Plateau, has posed many ecological challenges, which especially include the presence of considerable quantities of disturbed coal resources in open-pit mining areas. This study aims to achieve scientific and effective coal resource conservation during the ecological restoration of coal mines. Methods Focusing on the Jvhugeng mining area of the Muli coalfield, this study investigated the destruction characteristics of the coal resources in the open-pit mining area. From the perspective of geological mechanisms behind the destruction, this study artificially constructed the roofs of …
