Earth Sciences Commons^™

Latest Advances In Research On Co2-Enhanced Coalbed Methane Recovery, Sang Shuxun, Liu Shiqi, Li Dianshang, Zhang Shouren, Xu Tianfu, Han Sijie, Zhou Xiaozhi, Huang Fansheng, Liu Tong, Tian Yuchen, Zhang Helong, Niu Qinghe, Chen Yongchun, Zhang Bing, Wu Jie

Coal Geology & Exploration

Background The CO₂-enhanced coalbed methane recovery (CO₂-ECBM) technology integrates greenhouse gas emission reduction and enhanced CBM recovery, holding great significance for achieving the goals of peak carbon dioxide emissions and carbon neutrality of China and ensuring national energy security. However, due to limitations of insufficient fundamental research and some technical bottlenecks, the engineering application of the CO₂-ECBM technology remains in the engineering test stage. This study reviews the latest advances in research on the mechanisms, evaluation methods, and technical systems of CO₂-ECBM and explores key scientific issues and technical pathways for geological …

Key Issues And Research Prospects Of The Commingled-Production Compatibility Of Deep Superimposed Coalbed Methane Systems, Guo Chen, Wang Shuangming, Qin Yong, Xu Fengyin, Sun Xueyang, Xia Yucheng, Hou Enke, Wang Sujian, Sun Qiang, Wang Shengquan, Tang Shengli, Yang Xiankuo, Gao Junzhe, Li Ruiteng, Shi Kang

Coal Geology & Exploration

Objective In recent years, significant breakthroughs have been achieved in the exploration and exploitation of deep coalbed methane (CBM), which has emerged as a major area for the reserve growth and production addition of CBM in China. Variations in the temperature and pressure conditions of deep formations inevitably cause substantial differences in the commingled-production compatibility of deep and shallow superimposed CBM systems. Therefore, revealing the depth effects of the commingled-production compatibility is critical to enhancing the efficiency of the multi-layer commingled production of deep CBM and even coal-measure gas. Methods Using a systematic literature survey of the exploration and exploitation …

Ecological Restoration Strategies Based On Plant And Soil Characteristics For Dumps Of Surface Coal Mines In Cold Arid Regions, Wang Hao, Li Haichao, Jiang Xinjun, Cao Shumiao, Yang Fan, Wang Qiangmin, Xu Ganggang, Shi Hui

Coal Geology & Exploration

Objective The dumps of surface coal mines in cold arid regions represent ecologically vulnerable areas formed under extreme disturbance. However, a lack of systematic studies on the vegetation and soils in dumps, including their spatial variation patterns and synergistic mechanisms caused by vertical differences of the dumps, leads to insufficient theoretical bases for formulating differential ecological restoration strategies in engineering practice.Methods By integrating field ecological surveys and physicochemical tests in the laboratory, this study investigated the dump with elevations ranging from 2498 m-2632 m of the Heishan coal mine on the northern slope of the Tianshan Mountains, Xinjiang. Based …

Advances In Research On Eco-Geological Environment Monitoring Of Underground Coal Mining Areas Based On Airborne Remote Sensing, Li Jun, Zou Zhaohui, Zhang Chengye, Wang Yi, Cheng Yang, Xu Lianhang, Zhang Jinhe, Liu Chuanrui, Liang Lixia

Coal Geology & Exploration

Background Timely and effective monitoring of the current status of eco-geological environment holds great significance for scientific decision-making regarding both geological environment protection and ecological restoration in underground coal mining areas. Owing to its advantage of large-scale and rapid monitoring, airborne remote sensing technology has emerged as an important approach to the eco-geological environment monitoring of mining areas. Advances This study first clarifies relevant concepts of eco-geological environment monitoring, as well as the monitoring requirements and contents specific to underground coal mining areas. Accordingly, it presents a summary of the advances in research on airborne remote sensing technology for the …

From Follower To Leader: Seismic Coal Exploration Techniques In China Over The Past 70 Years−In Celebration Of The 70th Anniversary Of Ccteg Xi’An Research Institute (Group) Co., Ltd., Cheng Jianyuan, Wang Yunhong, Wang Baoli, Li Gang, Li Yuteng, Qin Si

Coal Geology & Exploration

Background After 70 years of innovation and development, China has successfully transformed from a follower into a leader in both high-resolution surface seismic coal exploration techniques and underground in-seam seismic exploration techniques for coal mines. Furthermore, it has achieved disruptive innovations in intelligent seismic-while-mining (SWM) and seismic-while-tunneling (SWT) techniques. These achievements have established China’s worldwide leading position in the overall development of seismic coal exploration techniques.Advances In terms of high-resolution surface seismic coal exploration techniques, China has undergone four development stages: arduously catching up, striving to follow, keeping pace with continuously, and overtaking international counterparts with advanced techniques during …

Sealing Performance Evaluation Criteria And Profile Optimization Of The Volumetric Cavities Of Positive Displacement Motors For Directional Drilling, Kuang Yuchun, Hu Xin, Zhou Jingpei, Luo Jinwu, Liu Yihui, Han Yiwei

Coal Geology & Exploration

Objective Constrained by complex stratigraphic conditions in underground coal mines, directional drilling faces challenges such as low efficiency when encountering medium-hard and hard formations. Positive displacement motors (PDMs) with a diameter of 89 mm are commonly used for directional drilling. Their efficiency is primarily influenced by the sealing performance of their volumetric cavities, which further significantly affects the drilling efficiency. Methods Based on the structural characteristics of the three-dimensional (3D) volumetric cavities of PDMs and the simulation method of two-way fluid-structure interactions, this study proposed the criteria for quantitatively evaluating the efficiency and volumetric cavity performance of PDMs, followed by …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

Biogeochemical Mechanisms Behind Water Quality Evolution And Valuable Element Reutilization Of Abandoned Mine Drainage: A Review, Wu Pan, Huang Jiangxun, Li Qingguang, Zhang Ruixue, Li Bo

Coal Geology & Exploration

Background Abandoned mine drainage, also known as acidic mine drainage (AMD), represents a major pollution source in mining areas while also serving as an important carrier of strategic critical metals and underground space utilization. In China, water pollution stemming from coal mining is more severe in the south than in the north. This spatial pattern is jointly shaped by climatic conditions, geological settings, and mining history. Advances From the perspective of the environmental geochemical frontier, this study presents a systematic review of AMD formation and evolution mechanisms, as well as technologies for water pollution prevention and control, resource recovery, and …

Underground Tunnel Drilling Technology And Equipment For Coal Mines In China: A 50-Year Retrospective And Prospects, Tian Hongliang, Li Wangnian, Li Quanxin, Yao Ke, Liu Jianlin, Chang Jianghua

Coal Geology & Exploration

Bcakground Underground tunnel drilling in coal mines represents an indispensable key means for the safe and efficient coal mining, precise disaster prevention and control, and geological transparency of coal mines. This study presents a systematic review of the development history of underground tunnel drilling technology and equipment for coal mines in China over the past 50 years, during which the technology and equipment have evolved from technology introduction to independent innovation and from following to keeping pace with and even to overtaking international counterparts.Advances Initially, this study expatiates on both the important position of coal resources in the national …

Key Techniques And Application Of The Zdy15000ldk High-Power Automatic Directional Drilling Rig, Li Quanxin, Zhang Gang, Fang Peng, Xing Wang, Yao Ke, Zhang Rui, Zhang Boyang, Zhao Xuefeng, Shi Yang, Sun Hanyu, Jia Qian

Coal Geology & Exploration

Objective For deep mining of coal mines, conventional directional drilling rigs face challenges including high labor intensity, limited control accuracy, a low intelligence level, and failure to meet the demand for efficient gas drainage. Meanwhile, high-power automatic drilling rigs encounter technical bottlenecks in automation, control accuracy, and process intelligence in this context. To address these issues, this study proposed an integrated and systematic solution—the ZDY15000LDK high-power automatic directional drilling rig. Methods Using a compact structural layout, a drill rod handling system was developed, consisting of a drill rod loading/unloading manipulator with four degrees of freedom and an automatic drill rod …

Instruments For Simulation Experiments On Coal-Rock Dynamic Disasters In China: Current Status And Key Challenges, Yuan Liang, Tang Haopeng, Ma Yankun, Wu Hua, Zhang Yachao, Jiao Biao, Wang Hao

Coal Geology & Exploration

Background Coal-rock dynamic disasters represent engineering disasters caused by the instability of the multi-phase and multi-field coupling of coal strata under mining disturbances, severely restricting the safe exploitation of deep coal resources. Elucidating the disaster-inducing mechanisms lays the foundation for exploring effective monitoring and early warning, along with prevention and control technologies, while instruments for simulation experiments provide crucial tools for investigating the mechanisms. Gradually increasing scientific and technological level has contributed to the continuous improvement in China's independently developed instruments for simulation experiments on coal-rock dynamic disasters. However, as engineering activities progressively extend toward deep parts, the multi-phase and …

Development History And Prospects Of Geological Guarantee In The Coal Industry: A Review, Liu Feng, Liu Wenming, Dong Shuning, Wang Hao, Cheng Jianyuan, Liu Zaibin, Fan Tao, Ma Liang, An Lin, Chen Baohui, Yan Zicheng, Jiang Bici

Coal Geology & Exploration

Background In China, the coal industry serves as a ballast stone and stabilizer for rapid socio-economic development and national energy security. Despite huge reserves, China’s coal resources are characterized by uneven spatial distribution, diverse coal seams, complex geological structures, and significantly different mining conditions. During coal mining, unclear geological conditions frequently lead to the abandonment of tunneling roadways, poor mining continuity, frequent equipment relocation, and the abrupt onset of concealed geologic hazards. These challenges ultimately result in difficult advancement of mining face, frequent casualties, and considerable economic losses. Geological guarantee represents a crucial foundation and key technology throughout the shaft …

Advances In Geological Guarantee Technologies For Safe, Efficient, And Intelligent Coal Mining In China, Sun Siqing, Miao Yaowu, Jia Lilong

Coal Geology & Exploration

Background Coal mining geology provides the foundation for efficient coal mining, as well as hazard prevention and control. Based on the revision to China’s normative documents entitled Regulations on Geological Work in Coal Mines and Detailed Rules for Geological Work in Coal Mines, the exploration of technologies for coal mining geology, and considerable experience in coal mine production practices, this study systematically reviews the advances in geological guarantee technologies for safe, efficient, and intelligent coal mining in China over the past four decades.Advances Six aspects of advances have been primarily achieved in geological guarantee technologies in China: (1) The …

Mechanisms Underlying Coal Instability During Coal And Gas Outbursts Induced By Deep Mining, Zhang Chaolin, Li Yunfu, Li Zhonghui, Wang Enyuan, Yang Shiji, Chen Jiawei, Wang Meng

Coal Geology & Exploration

Objective The gradual depletion of shallow coal resources drives a shift to the mining of deep coal seams. However, the complex deep mining environment significantly increases the potential risks and severity of coal and gas outbursts. Therefore, there exists an urgent need to investigate the mechanisms underlying the mechanical instability of coals under deep mining, aiming to provide guidance for the safe mining of deep coal mines.Methods By integrating physical experiments, numerical simulations, and theoretical analysis, this study investigated coal and gas outbursts under burial depths of 500 m, 1000 m, and 1600 m and established a multi-field coupling …

Analysis Of Typical Cases And Development Trends Of Coalbed Methane (Coal Mine Gas) Drainage Techniques In Coal Mining Areas, Hao Shijun, Jiang Wenping, Zhang Jing, Du Xinfeng, Mo Haitao, Duan Huijun

Coal Geology & Exploration

Background In the coal mining areas of China, coalbed methane (coal mine gas) occurs under complex conditions, rendering it difficult to achieve its efficient resource exploitation and effective hazard control using a single technique.Advances As indicated by the current state of the research, development, and engineering application of coalbed methane (coal mine gas) drainage techniques in China in recent years, the drainage methods can be classified into three categories according to their spatial arrangements: surface drainage, underground drainage, and surface-underground combined drainage. Furthermore, the surface and underground drainage methods can be subdivided into four types based on their temporal …

Key Techniques For Volume Fracturing Of Deep Coalbed Methane Reservoirs And Their Applications: A Case Study Of The Daning-Jixian Block, Li Shuguang, Xiong Xianyue, Zhen Huaibin, Bai Kunsen, Ji Yuan, Yuan Pu, Li Zhongbai, Zhu Weiping

Coal Geology & Exploration

Background Deep coalbed methane (CBM) reservoirs generally exhibit ultra-low porosity and permeability, high stress, predominance of nanopores, and complex fracture propagation. These characteristics complicate reservoir stimulation, thereby restricting the enhancement in single-well productivity and commercial exploitation. Since 2019, technologies for deep CBM recovery have evolved from volumetric acid fracturing, which highlights the enhancement of matrix permeability, into large-scale volume fracturing focusing on the elevation of both the fracture network scale and proppant efficiency. In 2023, ultra-large-scale volume fracturing aimed at maximizing estimated ultimate recovery (EUR) was further developed. However, the implementation of this novel technique poses challenges such as a …

Damage Evolution Of Coal Reservoirs Under Cyclic Disturbances And Optimization Suggestions For Deep Reservoir Stimulation, Chen Shida, Pu Yifan, Zhao Longmei, Li Xiang, Huang Li, Tang Dazhen, Zhang Yafei, Li Song, Tao Shu

Coal Geology & Exploration

Objectives and Methods During volume fracturing or multi-round hydraulic fracturing of deep coal reservoirs, pressure fluctuations induced by the propagation of fracture tips and fluid accumulation within fractures cause cyclic perturbations to surrounding rocks. To clarify both the mechanical responses of coals and the mechanisms behind fracture evolution within coal reservoirs under such cyclic perturbations, this study conducted triaxial cyclic loading-unloading tests on high-rank coals under varying confining pressures, stress amplitudes, and loading modes. In combination with field engineering data, this study proposed strategies for optimizing deep coal reservoir stimulation. Results and Conclusions The stress-strain curves of coals under cyclic …

Pathways And Modes For Prevention And Control Of Acid Mine Drainage-Induced Pollution In China, Liu Guo, Chen Qian, Gan Xinzhu, Tang Jie, Zhu Mingtan, Fan Jiajun, Ren Shuang

Coal Geology & Exploration

Background Mining activities in polymetallic sulfide mines significantly disrupt regional hydrogeochemical equilibrium, leading to the formation of acid mine drainage (AMD). Consequently, severe pollution of aquatic environments occurs, posing a threat to regional water resource security. To lay the foundation for the prevention and control of AMD-induced pollution, it is necessary to investigate the formation and evolution mechanisms of AMD and establish a low-cost, sustainable risk management and control mode. Methods Based on field sampling and literature research, this study made statistics of the hydrochemical characteristics of AMD from different polymetallic sulfide mining areas across China and elucidated the processes …

Advances In Research On The Quality, Influential Factors, And Contamination Prevention And Control Technologies Of Mine Water In Representative Coal Mining Areas Of China, Xu Guangquan, Zhang Haitao, Liang Miao, Chen Xiaoqing, Li Zixuan, Li Xu, He Jianghui

Coal Geology & Exploration

Background Mine water represents a major type of water body produced during coal mining. Investigating its quality, influential factors, and contamination prevention and control technologies is of great significance for environmental protection and the sustainable utilization of water resources in coal mining areas.Methods Based on field surveys and literature review, this study systematically analyzed the quality and formation mechanisms of mine water in representative coal mining areas of China. Furthermore, it explored the advances and primary challenges in current research on technologies for the prevention and control of mine water contamination and proposed major directions for future research. Advances …

Geophysical Responses And Their Statistical Relationships With Lithium And Kaolinite Contents For Lithium-Rich Coals In The Yangquan Mining Area, Chen Tongjun, Xu Haicheng, Li Wan

Coal Geology & Exploration

Objective China, representing the world's largest consumer of lithium resources, suffers from a limited endowment of conventional lithium resources, rendering it inevitable for China to seek to develop and utilize abundant coal-hosted lithium resources. Through a comparative analysis of coal samples from the lithium-rich No. 8 and the ordinary No. 15 coal seams in the Taiyuan Formation, Yangquan mining area, Shanxi Province, this study explored the statistical relationships between the lithium and kaolinite contents and geophysical responses. Accordingly, the feasibility of the indirect detection of coal-hosted lithium resources using geophysical methods was assessed. Methods First, by testing the lithium content …

Development Path And Prospects Of Technologies For Detecting Hidden Hazards In Coalfield Fire Zones, Deng Jun, Wang Jinrui, Ren Shuaijing, Song Zeyang, Wang Caiping, Li Yaqing, Lu Junhui, Qu Gaoyang

Coal Geology & Exploration

Background Hidden hazards in coalfield fire zones are characterized by limited detectability, rapid evolution, and multi-hazard coupling, posing major challenges to the safe coal mining and related ecological restoration. Methods This study aims to achieve the fine-scale identification and risk control of hidden hazards in coalfield fire zones. Based on a systematic review of the genetic mechanisms and spatial distribution patterns of coalfield fire zones, this study summarizes the characteristics of three primary fire zone types: outcrop/surface fire zones, shallowly buried fire zones, and deeply buried underground burnt-out areas and fire zones within old coal pits. Multi-dimensional hazards caused by …

Somatic Prosthetics For Planetary Resonance, Disha Dharesh Kumar R

Masters Theses

This thesis investigates how industrial design can transcend extractive technological paradigms in favor of relational interfaces that foster planetary attunement. Framing the climate crisis as a 'crisis of imagination', the research challenges the Western bifurcation of nature and culture by drawing on Indic cosmologies- which recognize stones, plants, and ecosystems as conscious at different levels and participants in a shared cosmic field. By synthesizing research in Biosemiotics, Quantum Information Pansycishm, and Neuroscience, the project redefines intelligence as a distributed, more-than-human phenomenon.

The research materializes as a speculative design artifact: a device that functions as a somatic prosthetic for planetary resonance. …

Riki&Dolphin: Real Time Data Transmission From The Bottom Of A Cave To A Website, Luca Tringali, Giacomo Canciani Dr., Tecla Tripari, Alexander Debenjak, Caterina Bearzotti

International Journal of Speleology

Coming from over 10 years of experience in cave monitoring in northeast Italy, Gruppo Speleologico Talpe del Carso, has designed Riki and Dolphin: customizable, low cost, and easy to assemble tools for getting real time data transmission from the bottom of a cave, even underwater, to a webserver. Their use has been tested to monitor air temperature inside the Abisso Bonetti Cave (Classical Karst, Italy), proving for the first time that a cave in Gorizian Karst can systematically be colder than the outdoor temperature even in winter, recording an internal temperature even lower than 0°C. The Dolphin device can be …

A Remote Sensing Approach To Identifying Zones Of Instability In Mine Tailings Impoundments Using Multi-Sensor Satellite Data, Arden K. Pierce

Honors Theses

Mine tailings impoundments are structures built to contain the chemical and sedimentary byproducts generated by ore extraction activities. In this common method of mining waste storage, the tailings can be pumped into containment ponds and held behind earthen embankments to prevent the release of hazardous substances into the surrounding environment. Monitoring environmental factors that influence the structural integrity of these impoundments is essential for identifying areas vulnerable to instability and failure. Soil moisture is a factor that can affect the stability of mine tailings impoundment structures. This study evaluates the relationship between satellite-derived soil moisture and surface deformation at mine …

Integrated Geophysical, Geotechnical, And Mineralogical Characterization Of Expansive Weches Formation Soils In East Texas: Implications For Infrastructure Design, Samuel Annobil

Electronic Theses and Dissertations

This study investigates the geotechnical, geophysical, and mineralogical characteristics of soils derived from the Weches Formation in Nacogdoches County, East Texas, with emphasis on the relationships among electrical resistivity, moisture condition, compaction state, and mineralogical composition. The Weches Formation is well known for producing clay-rich, moisture-sensitive soils that pose challenges to subgrade performance because of their plasticity and swelling behavior. Representative soil samples were collected and subjected to laboratory testing, including particle size analysis, Atterberg limits, Standard Proctor compaction, free swell tests, electrical resistivity measurements, and X-ray diffraction (XRD) mineralogical analysis. The soils are predominantly fine-grained and clay-rich, with USCS …

Mechanisms Behind The Impacts Of Co2 Concentration On Microbial Methanogenesis In Coal Seams, Wang Junyu, Liu Bingjun, Jiang Xiangqing, Chen Ruifeng, Xue Sheng, Zhou Wanlong, Yang Yundu

Coal Geology & Exploration

Background Coal seams exhibit the extensive distribution of a variety of indigenous functional microorganisms. Among these, some archaea enable methane metabolism using CO₂ as a substrate, providing the potential for the biological CO₂ storage and utilization in coal seams. However, conventional studies focus primarily on the degradation characteristics of coal matrix, leading to a lack of a systematic understanding of the mechanisms governing the adjustment of the methanation process in CO₂-bearing environments. Methods This study investigated the bituminous coals with a high volatile content in the Huainan mining area. Using laboratory-scale experiments on methanogenesis through anaerobic …

Dynamic Response Characteristics And Failure Mechanism Of Coal-Rock Combination Under Different Immersion Conditions, Zhang Xiangyang, Tong Zhipeng, Duan Yungang, Yang Weikun, Chen Jianben, Xu Linfeng

Coal Geology & Exploration

Background In practical engineering, the waterproof coal pillar usually suffers from different degrees of dynamic load from the overlying strata, and its internal water distribution is non-uniform. Although the traditional “water content” index can reflect the overall water content, it is difficult to describe the non-uniform characteristics of the soaking space. Therefore, it is of great significance to clarify the dynamic failure mechanism of coal and rock mass under different immersion conditions for stability zoning control. Methods On this basis, the coal–rock combined bodies under three different forms of immersion, namely: complete immersion, unilateral immersion, and non-immersion were prepared. These …

Mechanisms Underlying Lateral Force Applied To A Pdc Cutter On A Pdc Drill Bit During Rotary Rock Breaking, Wei Jiusen, Han Xin, Liu Wei, Gao Deli

Coal Geology & Exploration

Objective To improve the rock-breaking efficiency and durability of drill bits in the theoretical research on the optimal design of drill bits, the key is to systematically reveal both the rock-breaking mechanisms of polycrystalline diamond compact (PDC) cutters and the characteristics of forces applied to them. Methods Existing studies on rock breaking using a single PDC cutter generally adopt a linear or approximately linear cutting mode while neglecting the impacts of the radius of gyration. To address this issue, this study conducted experiments on cylindrical granite samples using a laboratory experimental setting for single-cutter rock breaking. With cutting depth and …

Strategic Layout And Optimization Paths Of The Standard System For The Exploration And Exploitation Of Deep Coalbed Methane, Chen Xinjun, Liu Zengqin, Shen Baojian, Zhao Shihu, Ye Jincheng, Zhang Jiaqi, Wang Tianyun

Coal Geology & Exploration

Objective In China, the deep coalbed methane (CBM) industry has emerged as a key sector for the reserve growth and production addition of natural gas. However, the current CBM technical standard system, which was developed based on shallow CBM practices, is incompatible with the demands for the exploration and development of deep CBM. To address this challenge, this study proposes the optimization paths of the current standard system, aiming to provide standardization support for large-scale exploitation of deep CBM.Methods Deep CBM reservoirs exhibit complex geological conditions of high temperature, pressure, and in-situ stress, as well as the CBM occurrence …

Structural Design And Parameter Optimization Of A Vibration Absorber For Rescue Casing-While-Drilling Rigs, Liu Pu, Yao Ningping, Zou Zujie, Fan Dong, Wei Hongchao, He Binjie

Coal Geology & Exploration

Objective Rescue drilling rigs undergo intense vibration at borehole mouths when operating in a confined underground space of coal mines. To address this issue, this study designed a compact multi-directional, passive dynamic vibration absorber, aiming to improve the operational stability and safety of the rigs. Methods Based on the spring-mass-damping system theory, a stepwise optimization design method was proposed for the longitudinal and transverse dynamic models of the vibration absorber. For the longitudinal vibration model, the particle swarm optimization (PSO) algorithm was applied for multi-objective parameter optimization. In contrast, for the transverse vibration model, the fixed point theory was employed …