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Full-Text Articles in Engineering

Fast Quantitative Interpretation Of Surface-Borehole Tem Using Transient Impulse Peak Time, Zhi Qingquan, Wu Junjie, Wang Xingchun, Yang Yi, Zhang Jie, Deng Xiaohong Jul 2022

Fast Quantitative Interpretation Of Surface-Borehole Tem Using Transient Impulse Peak Time, Zhi Qingquan, Wu Junjie, Wang Xingchun, Yang Yi, Zhang Jie, Deng Xiaohong

Coal Geology & Exploration

Due to the complex response law of the surface-borehole Transient Electromagnetic Method (TEM), qualitative analysis and semi-quantitative interpretation are the most widely used interpretation methods. However, the methods cannot obtain the resistivity parameter of the earth directly. To solve this problem, a fast quantitative interpretation method based on transient impulse peak time is proposed. Firstly, the expression of uniform half-space surface-borehole transient electromagnetic response is given, and the impulse time characteristics of surface-borehole transient electromagnetic response are analyzed. The results show that the deeper the receiving point is buried and the higher the earth conductivity is, the later the transient …


Key Technical Progress Of Water Cutoff Curtain Technology In Open-Pit Coal Mines In China, Huang Xuanming, Zhang Yan, Wang Mingxing, Teng Qingshan, Li Guozhi Jul 2022

Key Technical Progress Of Water Cutoff Curtain Technology In Open-Pit Coal Mines In China, Huang Xuanming, Zhang Yan, Wang Mingxing, Teng Qingshan, Li Guozhi

Coal Geology & Exploration

The method of pumping and discharging groundwater is widely used in open-pit coal mines for groundwater control in China to meet the requirements of safe coal mining, which causes great damage to water resources and seriously affects the ecological environment around coal mines. In recent years, with the all-round development of the economy, China has put forward higher requirements for ecological environment protection and ecological civilization construction. How to optimize and change the groundwater control mode and reduce the volume of pit drainage is a new subject generally in water prevention and control of open-pit coal mines. The use of …


Application And Effect Evaluation Of Water Cutoff Curtain Technology In Yuanbaoshan Open-Pit Coal Mine, Gao Sheng, Li Guozhi, Guo Yingjie, Tian Zenglin, Shao Dongmei, Zhu Hongjun Jul 2022

Application And Effect Evaluation Of Water Cutoff Curtain Technology In Yuanbaoshan Open-Pit Coal Mine, Gao Sheng, Li Guozhi, Guo Yingjie, Tian Zenglin, Shao Dongmei, Zhu Hongjun

Coal Geology & Exploration

Yuanbaoshan open-pit coal mine of Inner Mongolia is a rare extra large water rich open-pit coal mine at home and abroad. In order to resolve the problems of high production cost and high environmental risk caused by drainage for many years, it is plan to adopt water cutoff curtain technology to closure the seepage supply channel. By analyzing the hydrogeological and engineering geological conditions of the mine, the groundwater water control method of combining arc semi-closed curtain with group wells drainage hydraulic curtain was proposed. The curtain test study was carried out in the mine 452 m flat plate by …


Water Level Evolution Pattern Of Loose Layers Under Water Cutoff Curtain In Ecologically Fragile Open-Pit Mines, Wang Hai, Wang Yonggang, Zhang Yan, Sun Hao, Miao Hechao Jul 2022

Water Level Evolution Pattern Of Loose Layers Under Water Cutoff Curtain In Ecologically Fragile Open-Pit Mines, Wang Hai, Wang Yonggang, Zhang Yan, Sun Hao, Miao Hechao

Coal Geology & Exploration

Eastern Inner Mongolia of China is characterized by a fragile ecological environment and scarce water resources. High-intensity mining in open-pit coal mines has caused drastic changes in the recharge, runoff and discharge of the groundwater system, resulting in a significant drop in the water level of the loose layer, depletion of surface stream flow and destruction of the ecological environment. To reveal the evolution of water level in the loose layer under the water cutoff curtain in ecologically fragile open-pit mines, analyze the characteristics of groundwater distribution in and the influence of mining on the water level of loose layers, …


Ecological Restoration Strategies For Coal Mines In China Based On Vegetation Zones And Ecological Sensitivity, Zhou Hongxuan, Wang Zhaoqing, Pu Hongtong, Tao Guixin, Sun Jing Jul 2022

Ecological Restoration Strategies For Coal Mines In China Based On Vegetation Zones And Ecological Sensitivity, Zhou Hongxuan, Wang Zhaoqing, Pu Hongtong, Tao Guixin, Sun Jing

Coal Geology & Exploration

Coal is the main source of energy in China and the most important driver of our development for a long time. It is predicted that coal is going to be the main energy source for our social and economic development in the future. However, the long-term coal mining activities in China have caused serious damage to the ecological environment and comprehensive ecological restoration is urgently needed. At present, most coal mine ecological restoration is limited within a small scale in China, such as one or several mine areas, lacking of ecological restoration planning at the national spatial level, and corresponding …


Techniques Of Double-Pipe And Double-Acting Directional Drilling With Air In Broken And Soft Coal Seams In Underground Coal Mines, Wang Li Jul 2022

Techniques Of Double-Pipe And Double-Acting Directional Drilling With Air In Broken And Soft Coal Seams In Underground Coal Mines, Wang Li

Coal Geology & Exploration

In the broken and soft coal seam drilling, the outburst and collapse of the hole occur easily, resulting in shallow drilling depth and low rate of hole forming, which seriously restrict the efficient gas control in the broken and soft coal seam. With the rise of gas control models, such as replacing roadway with holes and progressive drainage of the broken and soft coal seam, higher requests have been put forward to the gas drainage hole. The further improvement of the drilling depth, drilling accuracy and hole forming rate of the broken and soft coal seam can meet the needs …


Water Control Principle Of Lateral Water Cutoff Curtain And Numerical Analysis Of Its Water Interception Effect In Yuanbaoshan Open-Pit Coal Mine——Taking Yuanbaoshan Open-Pit Coal Mine As An Example, Zhao Chunhu, Wang Mingxing, Cao Haidong, Qu Guowen, Wang Yong, Guo Yingjie Jul 2022

Water Control Principle Of Lateral Water Cutoff Curtain And Numerical Analysis Of Its Water Interception Effect In Yuanbaoshan Open-Pit Coal Mine——Taking Yuanbaoshan Open-Pit Coal Mine As An Example, Zhao Chunhu, Wang Mingxing, Cao Haidong, Qu Guowen, Wang Yong, Guo Yingjie

Coal Geology & Exploration

In the process of open-pit coal mining, drainage is an important aspect causing the loss of groundwater resources. Taking Yuanbaoshan open-pit coal mine in Chifeng City, Inner Mongolia as the research object, this paper analyzes the control principle of the curtain wall construction driven by open-pit mining on the groundwater system according to the hydrogeology of the study area and the characteristics of open-pit coal mine development. It comes to the conclusion that the weaker the permeability of the curtain wall, the greater the thickness, and shortening the distance from the recharge water body is the basic idea of reducing …


Research On Three-Component Responses Characteristics Of Axial Anisotropy Tunnel-Hole Transient Electromagnetic, Guo Jianlei, Gao Xiaowei, Hou Yanwei Jul 2022

Research On Three-Component Responses Characteristics Of Axial Anisotropy Tunnel-Hole Transient Electromagnetic, Guo Jianlei, Gao Xiaowei, Hou Yanwei

Coal Geology & Exploration

Large interpretation errors may exist in exploration areas with obvious conductivity anisotropy when applying tunnel-hole transient electromagnetic method. In this paper, the control equation is built by introducing the conductivity anisotropy tensor, which allows the current density of the rectangular loop source to be added into the Maxwell equation Ampere loop theorem based on the finite difference time domain (FDTD) algorithm in order to realize the loading of any current source. The control equation is discretized by the difference instead of the differential to realize the forward calculation of the tunnel-hole transient electromagnetic 3D model. Forward modeling is carried out …


Imaging Method Of Borehole Transient Electromagnetic Anomaly Response Boundary In Coal Mines Based On Clustering, Fan Tao, Li Ping, Zhang Youzhen, Zhao Rui, Fang Zhe, Fan Yilin, Liu Lei, Wang Cheng, Li Yuteng Jul 2022

Imaging Method Of Borehole Transient Electromagnetic Anomaly Response Boundary In Coal Mines Based On Clustering, Fan Tao, Li Ping, Zhang Youzhen, Zhao Rui, Fang Zhe, Fan Yilin, Liu Lei, Wang Cheng, Li Yuteng

Coal Geology & Exploration

In order to improve the ability to recognize and interpret the abnormal response boundary in the transient electromagnetic inversion imaging results of boreholes in coal mines, and to complete geophysical interpretation such as an accurate description of hidden water disasters in front of the heading face and a fine analysis of hidden disaster-causing factors, this paper proposes the application of apply clustering method of unsupervised machine learning to analyze the borehole transient electromagnetic processing results. According to the numerical distribution characteristics of resistivity and the characteristics of the two clustering methods, the K-Means clustering algorithm is selected to aggregate and …


Application Of Surface And Borehole Tem Joint Exploration In 2 000 M Deep Mineral Exploration, Wu Junjie, Liu Bin, Zhi Qingquan, Deng Xiaohong, Wang Xingchun, Yang Yi, Liu Dongming, Qiu Jinzhu Jul 2022

Application Of Surface And Borehole Tem Joint Exploration In 2 000 M Deep Mineral Exploration, Wu Junjie, Liu Bin, Zhi Qingquan, Deng Xiaohong, Wang Xingchun, Yang Yi, Liu Dongming, Qiu Jinzhu

Coal Geology & Exploration

Deep mineral exploration is a challenge. The borehole Transient Electromagnetic Method (TEM) goes deep underground through the sensor along the borehole, and gets closer to the deep target, so as to improve the ore discovery rate and prospecting effect. TEM is widely used in deep prospecting and exploration in foreign countries, and has achieved many important results. However, in China, due to the slow development of instruments, theoretical research and interpretation technology, it is less used in practical deep prospecting. This paper introduces a typical case about the 2 000 m deep prospecting in Baiyun Gold Deposit in Qingchengzi, Liaoning …


Application Of Borehole Transient Electromagnetic Method In Detection Of Floor Failure Depth In Fully Mechanized Top Coal Caving Face, Wang Cheng, An Youxin, Zhu Hongjun, Guo Jianlei Jul 2022

Application Of Borehole Transient Electromagnetic Method In Detection Of Floor Failure Depth In Fully Mechanized Top Coal Caving Face, Wang Cheng, An Youxin, Zhu Hongjun, Guo Jianlei

Coal Geology & Exploration

The carboniferous-Permian No. 6 coal seam in the eastern Jungar Coalfield of Ordos Basin is an extra-thick coal seam, and the coal floor is particularly threatened by the Ordovician limestone aquifer. The mining effect will lead to the formation of the bottom mining damage zone, and new water-conducting channels may be formed, which in turn will cause sudden water disasters. Aiming at the testing problem of floor mining failure zone, the method of transient electromagnetic method in hole with moving source and receiving is proposed to obtain resistivity characteristic data of strata from floor drilling before and after mining. Firstly, …


Present Study Situation Review Of Borehole Transient Electromagnetic Method, Sun Huaifeng, Zhang Yingying, Zhao Youchao, Liu Yuchao, Zhao Hualiang Jul 2022

Present Study Situation Review Of Borehole Transient Electromagnetic Method, Sun Huaifeng, Zhang Yingying, Zhao Youchao, Liu Yuchao, Zhao Hualiang

Coal Geology & Exploration

In the borehole transient electromagnetic method (TEM), the receiving probe is placed in the borehole, which is different from either aerial or ground TEM. In such methods, as the probe will be closer to the detection target and far away from surface, not only stronger response signals can be observed, but also the interference of various electromagnetic signals outside the borehole can be attenuated effectively. It can meet the demand of meticulous detection with large burial, especially the detection demand of deep blind ore and water hazard. The present situation of using various methods in the study in forward modeling, …


Mechanical Properties And Impact Energy Index Of Coal Affected By Gas Pressure And Evolutionary Mechanism, Ding Xin, Xiao Xiaochun, Pan Yishan Jul 2022

Mechanical Properties And Impact Energy Index Of Coal Affected By Gas Pressure And Evolutionary Mechanism, Ding Xin, Xiao Xiaochun, Pan Yishan

Coal Geology & Exploration

The frequent occurrence of gas emission and outburst accidents caused by rock bursts in deep coal seams poses a great threat to safe underground production. Therefore, clarifying the evolution law of the mechanical properties and burst potential of gas on coal and rock is the basis for establishing effective prevention and control measures. Using the self-developed visual coal fluid-solid coupling test system, we carried out the physical experiment to study the gas adsorption, mechanical properties and fragment distribution of coal affected by gas pressure, and analyzed the evolution characteristics and mechanism of the bursting energy index. The results show that …


Construction And Application Of Feasibility Evaluation Model For Gas Extraction In Goafs Of Abandoned Coal Mines, Yang Ming, Zhu Lin, Quan Xingyuan, Xu Jing, Liu Maomao, Zhang Tao Jul 2022

Construction And Application Of Feasibility Evaluation Model For Gas Extraction In Goafs Of Abandoned Coal Mines, Yang Ming, Zhu Lin, Quan Xingyuan, Xu Jing, Liu Maomao, Zhang Tao

Coal Geology & Exploration

Against the background of carbon neutrality and carbon peaking policy, the development of gas resources in abandoned coal mines can generate high resource, economic and environmental benefits. The evaluation index system is established through field research and literature review from technical feasibility and economic rationality aspects. The game theory-fuzzy comprehensive evaluation model is established by combining the weighting method of game theory with the fuzzy comprehensive evaluation method. The abandoned Gushuyuan Mine is used as an example to verify the rationality of the evaluation model. The weights of gas resource conditions and gas preservation conditions in the first-level indicators are …


Distribution Characteristics And Formation Mechanism Of High Salinity Groundwater In Northeast Ningdong Coalfield, Jin Dewu, Wang Tiantian, Zhao Baofeng, Li Debin, Zhou Zhenfang, Shang Hongbo Jul 2022

Distribution Characteristics And Formation Mechanism Of High Salinity Groundwater In Northeast Ningdong Coalfield, Jin Dewu, Wang Tiantian, Zhao Baofeng, Li Debin, Zhou Zhenfang, Shang Hongbo

Coal Geology & Exploration

High salinity groundwater is widely and unevenly distributed in northeast Ningdong Coalfield of Ningxia Hui Autonomous Region, and it varies greatly throughout the coalfield. This paper studies the distribution characteristics and formation mechanism of high salinity groundwater. Firstly, spatial distribution characteristics of high salinity groundwater was researched, and then, Piper trilinear graph, Gibbs graph and ion proportionality coefficient were used to investigate the formation mechanism of high salinity groundwater. The results show that groundwater salinity value varies from 0.30 g/L to 23.56 g/L, and the average value is 5.84 g/L. The proportions of fresh water, brackish water, salt water and …


Landscape Planning Model Design And Layout Of Loess Hills In Coal Mining Area Of Northern Shaanxi:A Study Of The Subsidence Area Of Ningtiaota Coal Mine, Shang Jianxuan, Gao Yakun, Yang Fan, Bi Yinli, Quan Wenzhi, Ma Shaopeng, Zhang Yanxu Jul 2022

Landscape Planning Model Design And Layout Of Loess Hills In Coal Mining Area Of Northern Shaanxi:A Study Of The Subsidence Area Of Ningtiaota Coal Mine, Shang Jianxuan, Gao Yakun, Yang Fan, Bi Yinli, Quan Wenzhi, Ma Shaopeng, Zhang Yanxu

Coal Geology & Exploration

The coal mining area of northern Shaanxi is an important coal base of China, and the large amount of coal mining will cause surface subsidence and landscape disturbance. Taking the subsidence area of Ningtiaota Mine in northern Shaanxi as an example, this paper comprehensively analyzes the landscape problems in loess hilly landform through the combination of indoor statistical analysis, field investigation, qualitative-quantitative methods. The landscape pattern planning, design and layout are carried out, which provides reference for the landscape planning of underground mine area in this landform types. It is found that there are four problems in the above ground …


Influence Of Coal Mining On Shallow Groundwater Environment Response To Coal Mining And Mine Water Ecological Utilization Analysis, Chai Jianlu Jul 2022

Influence Of Coal Mining On Shallow Groundwater Environment Response To Coal Mining And Mine Water Ecological Utilization Analysis, Chai Jianlu

Coal Geology & Exploration

The contradiction between coal and water is prominent in the upper and middle reaches of the Yellow River Basin, and coal mining activities has caused certain damage to groundwater environment in those areas. So the quantity and quality characteristics of mine water for the Yushenfu mining area in Yulin City of northern Shaanxi Province were analyzed to reveal the influence of coal mining on the groundwater environment, and the ecological utilization study of mine water was also carried out based on field investigation, data analysis and laboratory tests. The results show that the mine water content coefficient in the study …


Evaluation Of Resources And Environment Carrying Capacity Of Xilinhot Mining Area Based On Multi-Source Data, Sun Jundong, Song Renzhong, Li Feiyue, She Changchao, Guo Tianyu, Li Jun, Zhang Chengye Jul 2022

Evaluation Of Resources And Environment Carrying Capacity Of Xilinhot Mining Area Based On Multi-Source Data, Sun Jundong, Song Renzhong, Li Feiyue, She Changchao, Guo Tianyu, Li Jun, Zhang Chengye

Coal Geology & Exploration

The mining and depletion of coal resources have a certain degree of impact on the environment and population of the coal mining area. Confronted with the resources and environment problems, China strongly advocates the construction of green mines, requiring that mine exploitation must be within resources and environment carrying capacity. With the support of multi-source data (Landsat 8, GF-2, etc.) and socio-economic statistics data, Analytic Hierarchy Process was used to construct an index system for evaluating resources and environment carrying capacity of the mining area in Xilinhot, Inner Mongolia from two aspects of the carrying background and the carrying statu. …


Structure Optimization And Drilling Capacity Analysis Of A Self-Propelled Straight-Swirling Mixed Jet Bits, Du Peng, Zhang Wending Jul 2022

Structure Optimization And Drilling Capacity Analysis Of A Self-Propelled Straight-Swirling Mixed Jet Bits, Du Peng, Zhang Wending

Coal Geology & Exploration

As the core part of hydro-jet radial drilling technology for coal-measure gas extraction, the self-propelled jet drill bit has a decisive impact on drilling efficiency. In order to obtain the optimal parameters of the direct rotating mixed jet, the velocity characteristics of the three-dimensional flow field with different bit structure parameters are analyzed by the combination of Fluent numerical simulation and specific experiments, and the optimization criteria are given. The optimal parameters of the drill bit are obtained in the drilling test: the central hole of diameter 1.2 mm, the impeller groove of width 0.7 mm, the impeller of thickness …


Wetland Soil Development Along Salinity And Hydrogeomorphic Gradients In Active And Inactive Deltaic Basins Of Coastal Louisiana, Amanda Fontenot Jul 2022

Wetland Soil Development Along Salinity And Hydrogeomorphic Gradients In Active And Inactive Deltaic Basins Of Coastal Louisiana, Amanda Fontenot

LSU Master's Theses

Coastal wetlands provide an abundance of ecosystem services that benefit society, such as essential habitat for commercial species, storm protection, nutrient cycling, and carbon storage. Louisiana faces rapid rates of relative sea level rise (natural subsidence and eustatic sea levels) that threaten wetland survival, which are amplified by a reduction of riverine sediment input. An important determining factor of marsh survival is the formation of wetland platform elevation, known as vertical accretion, which is determined by several processes including sediment deposition & erosion, below ground biomass (BGB) productivity, decomposition of organic matter, shallow & deep subsidence, and soil compaction. Feldspar …


Research Advances Into Mine Safety Science And Engineering, Hani Mitri, Rudrajit Mitra, Ting Ren Jul 2022

Research Advances Into Mine Safety Science And Engineering, Hani Mitri, Rudrajit Mitra, Ting Ren

Journal of Sustainable Mining

No abstract provided.


Carbon Capture, Utilization, And Storage, University Of North Dakota. Energy And Environmental Research Center Jul 2022

Carbon Capture, Utilization, And Storage, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about carbon capture, utilization, and storage (CCUS) and the Energy & Environmental Research Center’s CCUS capabilities. Includes information on the Plains CO2 Reduction (PCOR) Partnership initiative, Brine Extraction and Storage Test (BEST), Carbon Storage Assurance Facility Enterprise (CarbonSAFE), Red Trail Energy Carbon Capture and Storage, a feed study at Coal Creek Station, Bell Creek and Cedar Creek anticline projects, and Partnership for CO2 Capture (PCO2C). [This item is an outdated or superseded version and retained for historical purposes only. It may no longer reflect current information, policies, or practices.]


Study On The Effect Of Coal Microscopic Pore Structure To Its Spontaneous Combustion Tendency, Xianwei Dong, Gaojing Li, Xuanmeng Dong, Fusheng Wang Jun 2022

Study On The Effect Of Coal Microscopic Pore Structure To Its Spontaneous Combustion Tendency, Xianwei Dong, Gaojing Li, Xuanmeng Dong, Fusheng Wang

Journal of Sustainable Mining

Coal is a porous medium. Due to the large number of pores in coal and the pore size on its surface, usually ranging from millimeter to nanometer, it is difficult to measure and analyze the microscopic pore structure of coal. In order to investigate the effect of the microscopic pore structure of coal on its spontaneous combustion tendency, coal samples from different coal mines of the Kailuan Group were selected as the research objects, and the data of the microscopic pore distribution of three different coal samples were measured by using mercury injection apparatus. The regression analysis of microscopic pore …


An Integrated Approach For Dynamic Process Modeling And Optimization Of Wastewater Treatment Facilities, Komal Rathore Jun 2022

An Integrated Approach For Dynamic Process Modeling And Optimization Of Wastewater Treatment Facilities, Komal Rathore

USF Tampa Graduate Theses and Dissertations

The subareas of process systems engineering including process modeling, simulation, and optimization are becoming progressively substantial for understanding processes, making decisions, improving efficiency, and complying with stricter environmental and safety legislation. Additionally, the availability of user-friendly flowsheet simulators and computational resources with the current trend of data collection and analysis has allowed for a more accurate representation of complex processes such as wastewater treatment systems. Despite all the progress in the areas of process modeling and simulation, the first-principle mechanistic models for wastewater treatment processes are at best employed during the design stage, and therefore, not used optimally for day-to-day …


Q-P Curve Equation Of Geothermal Well Recharge Test In The Urban Area Of Mei County, Western Guanzhong, Shen Xiaolong, Li Hao, Wang Wei, Cheng Zhouying Jun 2022

Q-P Curve Equation Of Geothermal Well Recharge Test In The Urban Area Of Mei County, Western Guanzhong, Shen Xiaolong, Li Hao, Wang Wei, Cheng Zhouying

Coal Geology & Exploration

Clarifying the relationship between recharge pressure (p) and recharge volume (Q) is crucial for regional green and sustainable geothermal development in geothermal well recharge. The preliminary data of well G102 recharge test in Mei County in the western Guanzhong area were optimized, and three sets of data were determined to clarify this relationship. According to the data, the Q-p curve was drawn. Based on the characteristics of five types of curves in the pressurized water test, it was judged that the curves might be parabolic, logarithmic, and hower function. Therefore, three types of curves were drawn, …


Table Of Contents, The Editors Jun 2022

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.


Experimental Study On The Migration And Distribution Law Of Pulverized Coal In Roadway During Coal And Gas Outburst, Zhang Chaolin, Wang Yibo, Wang Enyuan, Zeng Wei, Wang Peizhong Jun 2022

Experimental Study On The Migration And Distribution Law Of Pulverized Coal In Roadway During Coal And Gas Outburst, Zhang Chaolin, Wang Yibo, Wang Enyuan, Zeng Wei, Wang Peizhong

Coal Geology & Exploration

Coal and gas outburst is one of the geological disasters that seriously threaten coal mine safety production, and its main disaster forms are gas suffocation, impact and burial of pulverized coal. In this paper, the coal and gas outburst experiments under different gas pressures were carried out using the self-developed multi-functional test system for coal and gas outburst simulation. The results show that the gas entrains the pulverized coal and sprays into the roadway in a jet shape after the outburst is triggered. The gas expansion energy is under the pressure of 0.35 MPa and the initial acceleration of outburst …


Risk Assessment Of Floor Water Inrush By Weighted Rank Sum Ratio Based On Combination Weighting, Yao Hui, Yin Shangxian, Xu Wei, Zhang Runqi, Jiang Zhiting Jun 2022

Risk Assessment Of Floor Water Inrush By Weighted Rank Sum Ratio Based On Combination Weighting, Yao Hui, Yin Shangxian, Xu Wei, Zhang Runqi, Jiang Zhiting

Coal Geology & Exploration

Deep mining of the coal seam causes frequent water hazards in the coal mine floor. As the disadvantages of traditional water inrush risk assessment methods, such as single evaluation index and deviation of the evaluation results from reality are gradually revealed, many new assessment methods are emerging. In this paper, Donghuantuo Coal Mine, a North China type coalfield, in Hebei province is taken as the research object. The evaluation factor sets including aquifer capacity, aquifuge capacity, geological conditions and coal seam conditions are selected, and with ten evaluation factors being considered, a floor water inrush risk evaluation index system applicable …


Cross Wavelet Analysis Between Layered Monitoring Data Of Stratum Deformation And Groundwater Level Regime, Kong Xiangru Jun 2022

Cross Wavelet Analysis Between Layered Monitoring Data Of Stratum Deformation And Groundwater Level Regime, Kong Xiangru

Coal Geology & Exploration

Land subsidence is usually caused by over-exploitation of groundwater, and its occurrence and development have a certain lag relative to the change in groundwater level. Obtaining the accurate lag time of land subsidence has always been an important topic in land subsidence research. Based on the layered monitoring data of the long-time series of land subsidence and groundwater level regime from 2008 to 2018 by Land Subsidence Monitoring Station in Pinggezhuang, Beijing, the lag effect between stratum deformation in layers at different depths and groundwater level regime is analyzed in this paper by adopting methods of Mann Kendall trend test, …


Sequence-Paleogeography And Coal Accumulation Of The Paleogene Hunchun Formation In The Hunchun Basin, Hou Haihai, Li Qiangqiang, Shao Longyi, Fan Xuejie, Liang Guodong, Li Yanan Jun 2022

Sequence-Paleogeography And Coal Accumulation Of The Paleogene Hunchun Formation In The Hunchun Basin, Hou Haihai, Li Qiangqiang, Shao Longyi, Fan Xuejie, Liang Guodong, Li Yanan

Coal Geology & Exploration

The Hunchun Basin is an important coal-bearing region in Jilin Province, northeastern China. The analysis of the sedimentary paleogeography of the Paleogene Hunchun Formation and coal-accumulation law in the sequence framework provides a theoretical basis for future coal and coalbed methane exploration. The lithofacies, sedimentary systems, sequence paleogeography, and coal accumulation characteristics were analyzed based on regional geology, drilling cores and well logging data. The results show five rock types, including gravel, sandstone, siltstone, mudstone, and combustible organic rock, and twelve lithofacies. The Hunchun Formation was divided into three third-order sequences by three sequence interfaces, including the regional unconformity surface, …