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- Keyword
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- Numerical simulation (87)
- Coalbed methane (47)
- Coal mine (39)
- Ordos Basin (29)
- Gas drainage (28)
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- Deep learning (27)
- Pore structure (27)
- Permeability (25)
- Deep coalbed methane (24)
- Hydraulic fracturing (23)
- Tar-rich coal (23)
- Coalbed methane (CBM) (21)
- Directional drilling (20)
- Underground coal mine (19)
- Coal (17)
- Deep coalbed methane (CBM) (17)
- Qinshui Basin (15)
- Horizontal well (14)
- Open-pit coal mine (14)
- Rock burst (14)
- Underground coal gasification (UCG) (13)
- Fracture (12)
- Machine learning (12)
- Prospect (12)
- Shale gas (12)
- Helium (11)
- Intelligent mining (11)
- Mine water (11)
- Advanced detection (10)
- CBM (10)
- Publication Year
Articles 1201 - 1230 of 1775
Full-Text Articles in Oil, Gas, and Energy
Research On Three-Component Response Of Ground-Airborne Tem Considering Emission Current Waveform, Hou Yanwei, Guo Jianlei, Si Yinnyu, Jiang Tao
Research On Three-Component Response Of Ground-Airborne Tem Considering Emission Current Waveform, Hou Yanwei, Guo Jianlei, Si Yinnyu, Jiang Tao
Coal Geology & Exploration
The ground-airborne TEM has received more and more attention in coal goaf exploration and other fields. In order to provide a theoretical basis for the processing and interpretation of ground-airborne transient electromagnetic data, it is necessary to study the influence of the transmitted current waveform parameter on the three-component response characteristics of ground-airborne TEM. Taking trapezoidal waves as an example, this article firstly studies the frequency distribution of different emission current waveform, and then investigates the effects of the rising edge time, pulse width and turn-off time of the transmitted waveform on the three-component magnetic field response of ground-air transient …
Research On The Integrated Electric Exploration System For Coal Mines And Its Application, Liu Baobao, Guo Chun, Yang Haitao
Research On The Integrated Electric Exploration System For Coal Mines And Its Application, Liu Baobao, Guo Chun, Yang Haitao
Coal Geology & Exploration
In order to overcome the shortcomings of the existing electrical prospecting technology in coal mines, such as multiple construction of electrical sounding, electrical profile and electrical penetration and a scarcity of data collected, an integrated electrical prospecting system is successfully designed, absorbing the idea of parallel electrical data acquisition, and applying the "rectangular wave" electrode layout mode combined with the "multi device data extraction" technology. The experimental results show that the system can complete the original data acquisition of electrical sounding, electrical profile, electrical perspective and other electrical construction methods with one-time wiring and one-round power supply, and extract the …
Collapse Filling-Based Technology Of Weakening And Danger-Solving By Staged Fracturing In Hard Roof, Zheng Kaige, Yang Junzhe, Li Bingang, Li Yanjun, Dai Nan, Yang Huan
Collapse Filling-Based Technology Of Weakening And Danger-Solving By Staged Fracturing In Hard Roof, Zheng Kaige, Yang Junzhe, Li Bingang, Li Yanjun, Dai Nan, Yang Huan
Coal Geology & Exploration
The working face is easy to induce dynamic disasters such as rock burst, coal and gas outburst, mine earthquake and hurricane in goaf under the condition of hard roof, which seriously threatens the safety of mine production. the pre-weakening and risk-solving technology of staged fracturing in hard roof is proposed based on the mode of advanced weakening by staged fracturing through open holes, combined with the synergetic support concept with "fracturing collapse body+coal pillar+load-bearing rock layer". By using the methods of theoretical analysis, technical research and development and engineering application, the crisis mechanism of advanced weakening of the staged fracturing …
Development Characteristics And Controlling Factors Of Coal-Measure Source Rocks In The Global Tethys Region, Qu Tong, Huang Zhilong, Wang Rui, Tan Sizhe, Li Zhiyuan, Guo Xiaobo, Zhao Jing, Pan Yongshuai
Development Characteristics And Controlling Factors Of Coal-Measure Source Rocks In The Global Tethys Region, Qu Tong, Huang Zhilong, Wang Rui, Tan Sizhe, Li Zhiyuan, Guo Xiaobo, Zhao Jing, Pan Yongshuai
Coal Geology & Exploration
Under the control of tectonic activity in the Tethys region, a series of basins with coal measure source rocks developed, and the Tertiary coal in the circum Pacific belt is characterized by "hydrogen-rich" and has great hydrocarbon generation potential.This type of coal measure strata is an important source rock in petroliferous basins along the southeast coast of China.Therefore, it is particularly important to systematically analyze the development characteristics and controlling factors of coal measure source rocks under the Tethys background. Based on the systematic analysis of the development age, environments, geochemical characteristics and biomarker characteristics of the coal measure source …
Application Of Surface Nuclear Magnetic Resonance Technology In Detecting Water Abundance In Concealed Burnt Zone, Hou Enke, Fan Jiangwei, Gao Lijun, Wang Jianwen, Chen Dehai, Chi Baosuo, Wang Hongke
Application Of Surface Nuclear Magnetic Resonance Technology In Detecting Water Abundance In Concealed Burnt Zone, Hou Enke, Fan Jiangwei, Gao Lijun, Wang Jianwen, Chen Dehai, Chi Baosuo, Wang Hongke
Coal Geology & Exploration
The overlying bedrock composite aquifer(including weathered bedrock and burnt rock aquifer) in the concealed burnt zone of coal seams is one of the main threats to coal mining. It is of great significance to clarify the water enrichment of the concealed burnt zone for the prevention and control of coal mine water hazards. Ningtiaota Coal Mine, which has experienced a large water inrush accident, was used as the research object, and the Surface Nuclear Magnetic Resonance(SNMR) was used to detect the water enrichment of the aquifer in the concealed burnt area. The results show that there are two aquifers in …
Improvement And Test Of Radar Imaging Logging Tool For Oil And Gas Wells, Zhao Yonggang
Improvement And Test Of Radar Imaging Logging Tool For Oil And Gas Wells, Zhao Yonggang
Coal Geology & Exploration
The detection depth of traditional logging tools is basically less than 3 m, and without azimuth resolution, the formation structure in larger area around wells cannot be imaged. Therefore the problems arising in the detection of subtle structure and oil and gas reservoirs can not be solved. In response to such problems, radar imaging logging tool is developed by applying ground penetrating radar imaging technology to logging. In order to improve the detection depth, azimuth resolution and downhole depth of the tool, a nanosecond pulse source and directional receiving antennae are used to detect and image the formation around the …
Table Of Contents, The Editors
Medium Conditons And Influence Mechanism Of High Salinity Mine Water Transfer And Storage By Deep Well Recharge, Li Xin, Sun Yajun, Chen Ge, Wang Houzhu, Zhang Zhijun
Medium Conditons And Influence Mechanism Of High Salinity Mine Water Transfer And Storage By Deep Well Recharge, Li Xin, Sun Yajun, Chen Ge, Wang Houzhu, Zhang Zhijun
Coal Geology & Exploration
In the arid and semi-arid regions of the Western China, there is not only a shortage of water resources, but also the problems of large mine water inflow and high salinity of mine water. In order to reduce the waste of water resources in the mining activities and protect water ecological environment in the region, it is proposed to treat the mine water by deeper well recharge to the aquifers under the coal seam based on the theories and technical methods such as mine water transfer and storage, water-preserving mining and coal-water dual resource coordinated mining. A test well project …
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 …
Mine Water Drainage Pollution In China's Coal Mining Areas And The Construction Of Prevention And Control Technical System, Sun Yajun, Xu Zhimin, Li Xin, Zhang Li, Chen Ge, Zhao Xianming, Gao Yating, Liu Qi, Zhang Shangguo, Wang Weijun, Zhu Lulu, Wang Sheng
Mine Water Drainage Pollution In China's Coal Mining Areas And The Construction Of Prevention And Control Technical System, Sun Yajun, Xu Zhimin, Li Xin, Zhang Li, Chen Ge, Zhao Xianming, Gao Yating, Liu Qi, Zhang Shangguo, Wang Weijun, Zhu Lulu, Wang Sheng
Coal Geology & Exploration
Mining activities are bound to produce enormous mine water drainage. Mine water in China shows relatively poor water quality and high cost of water treatment and other problems. Firstly, the main characteristics of mine water quality in China's typical mine areas are clarified in this paper: conventional ions are the main chemical components causing poor mine water quality; mine water has a small proportion of toxic and harmful substances, which is generally better than the quality standard of class Ⅲ groundwater. Secondly, some scientific issues on the formation and evolution of mine water quality are discussed in detail, including the …
Coupling Simulation Of Groundwater Dynamics And Solute Transfer In The Process Of Deep Reinjection Of Mine Water, Zhao Chunhu, Yang Jian, Wang Shidong, Zhou Jianjun, Xu Feng, Liu Ji
Coupling Simulation Of Groundwater Dynamics And Solute Transfer In The Process Of Deep Reinjection Of Mine Water, Zhao Chunhu, Yang Jian, Wang Shidong, Zhou Jianjun, Xu Feng, Liu Ji
Coal Geology & Exploration
The deep well reinjection of mine water is a main form of "transfer storage" treatment of mine water. According to the geological and mine water characteristics of the coal mine area in Ordos Basin, the paper puts forward the basis for selecting the target layer of mine water reinjection from the perspective of good matching between groundwater and mine water in the target layer of reinjection, the water isolation of upper and lower strata, permeability and sealing of the reinjection layer. Based on Darcy's law of groundwater and Dupuit's theory, a mathematical model of steady flow of water injection well …
Heavy Metal Pollution Characteristics And Source Analysis Of Water Drainage From A Mine In Inner Mongolia, Wang Tiantian, Jin Dewu, Yang Jian
Heavy Metal Pollution Characteristics And Source Analysis Of Water Drainage From A Mine In Inner Mongolia, Wang Tiantian, Jin Dewu, Yang Jian
Coal Geology & Exploration
Heavy metal pollution evaluation and its source analysis are essential to mine water reuse and protection of ecological environment in mining areas. The objective of this paper is to study heavy metal pollution characteristics and source of heavy metal in mine water. A coal mine from Inner Mongolia Province was chosen as the study area and 49 water samples including surface water, quaternary groundwater, confined groundwater and mine water were collected. Primarily, we detected the concentrations of Zn, Pb, Fe, Mn, As, Cu, Cd, Cr, Hg and Se of water samples to explore heavy metal pollution characteristics and excessive situation. …
Hydrochemical Characteristics And Genetic Mechanism Of High Tds Groundwater In Xinjulong Coal Mine, Zhang Yuzhuo, Xu Zhimin, Zhang Li, Lyu Weikui, Yuan Huiqing, Zhou Lijie, Gao Yating, Zhu Lulu
Hydrochemical Characteristics And Genetic Mechanism Of High Tds Groundwater In Xinjulong Coal Mine, Zhang Yuzhuo, Xu Zhimin, Zhang Li, Lyu Weikui, Yuan Huiqing, Zhou Lijie, Gao Yating, Zhu Lulu
Coal Geology & Exploration
Based on historical water quality data and sampling test results, using Piper three-line diagram, correlation analysis, hydrogen and oxygen isotope, Gibbs diagram, ion ratio and saturation index, etc., the hydrochemical characteristics and genetic mechanism of the groundwater with high TDS in Xinjulong Coal Mine area were explored. The results show that with the proceeding of mine construction and coal mining, the water chemistry environment in the study area has changed. The water chemistry type is no longer a single SO4-Na type, with SO4·HCO3-Na and SO4-Ca·Mg type appearing in the deep limestone water. …
Confirmation Of Carbon Emissions In Coal Mining Areas And Research On Low-Carbon Green Development Path, Wang Meng, Ma Ruying, Dai Xuguang, Shan Yadi
Confirmation Of Carbon Emissions In Coal Mining Areas And Research On Low-Carbon Green Development Path, Wang Meng, Ma Ruying, Dai Xuguang, Shan Yadi
Coal Geology & Exploration
Analysis was carried out on the issues such as unclear boundaries of carbon emission sources in coal mining areas, lack of accounting models, and development directions in the context of carbon neutrality. Based on the previous researches and through literature review, data collection and other methods, the boundaries of carbon emission sources in coal mining areas have been clarified and accounting model has been established, clarifying the low-carbon and green development direction of coal mining areas. The sources of carbon emissions(CH4 and CO2) in coal mining areas are divided into two major categories: natural emission and anthropogenic …
Gas Emission-Based Determination Of The Reasonable Driving Speed In Coal Roadway, Fu Shuai, Si Qingmin, Wang Qifei, Guo Xinyao, Zhang Hongtu
Gas Emission-Based Determination Of The Reasonable Driving Speed In Coal Roadway, Fu Shuai, Si Qingmin, Wang Qifei, Guo Xinyao, Zhang Hongtu
Coal Geology & Exploration
Scientific determination of the tunneling speed is an important prerequisite for the safe and efficient production in coal mines with high gas and outburst. In order to determine the reasonable driving speed of coal roadway and reduce the occurrence of dynamic disasters in coal roadway driving, the distribution law of gas in roadway head was analyzed, the mathematical model was established. Gas emission characteristics were also analyzed at different driving speeds based on the model. Taking Jinhui Wanfeng Coal Mine as an example, the reasonable driving speed was determined in this coal mine based on its gas emission characteristics. Results …
Slippage Effect And The Seepage Mechanism Considering The Compaction And Embedding Action Of Proppant, Cheng Qiaoyun, Li Bobo, Li Jianhua, Gao Zheng, Wang Bin
Slippage Effect And The Seepage Mechanism Considering The Compaction And Embedding Action Of Proppant, Cheng Qiaoyun, Li Bobo, Li Jianhua, Gao Zheng, Wang Bin
Coal Geology & Exploration
Hydraulic fracturing technology is an effective method to improve the efficiency of coalbed methane drainage, but the universal embedding of proppant under stress will change the width of the fractures, which will affect the gas slippage effect and the permeability mechanism. In order to explore the gas slippage effect and coal seepage law under the background of hydraulic fracturing, the Hertzian contact theory is used to quantify the embedding depth of proppant, and the gas slippage coefficient calculation equation and permeability model of the combined effect of proppant and effective stress are constructed. The results show that under different gas …
Study On P-Wave Velocity And Mechanical Response Characteristic Of Rock In Coal Seam Roof With Supercritical Co2 Injection, Chen Chen, He Xingyi, Niu Qinghe, Yu Hongxu, Xie Xiangyu
Study On P-Wave Velocity And Mechanical Response Characteristic Of Rock In Coal Seam Roof With Supercritical Co2 Injection, Chen Chen, He Xingyi, Niu Qinghe, Yu Hongxu, Xie Xiangyu
Coal Geology & Exploration
Deep coal seam CO2 geological sequestration and enhanced CH4 recovery(CO2-ECBM) can both increase CBM recovery and achieve carbon emission reduction, possessing dual benefits of energy and environment. The geochemical reactions between supercritical CO2(ScCO2), water and coal seam roof can change its physical-mechanical properties and increase the risk of CO2 leakage. In this paper, taking the roof rock of No.3 coal seam in Hudi Mine from Qinshui Basin as the research area, the ScCO2-water-rock geochemical reaction simulation experiment was carried out to explore the geochemical reaction process of ScCO2 …
Adsorption Phase Density Characteristics Of Supercritical Methane Of Granular Coal, Zhang Mingjie, Liu Hao, Jia Tianrang, Gong Ze, Yang Mingxin
Adsorption Phase Density Characteristics Of Supercritical Methane Of Granular Coal, Zhang Mingjie, Liu Hao, Jia Tianrang, Gong Ze, Yang Mingxin
Coal Geology & Exploration
Finding out the characteristics of supercritical methane adsorption phase density of granular coal is the basis of studying the influence of temperature and pressure on methane adsorption amount of coal sample. Granular coal samples collected from Hebi No.6 Mine and Longshan Mine in Anyang-Hebi Coalfield were used to measure the isothermal adsorption lines at temperatures of 308 K, 313 K and 318 K, and pressures of 1-24 MPa by magnetic suspension balance isotherm adsorption device. The intercept method, Langmuir ternary model fitting method and liquid phase density method were used to calculate the adsorbed phase density at adsorption saturation and …
De-Blocking Technology And Application Of High-Rank Cbm Well In Junlian Region In Sichuan Province, Peng Lisha, Zhang Yimin, Xiong Wei, Zhao Dan, Luo Kai
De-Blocking Technology And Application Of High-Rank Cbm Well In Junlian Region In Sichuan Province, Peng Lisha, Zhang Yimin, Xiong Wei, Zhao Dan, Luo Kai
Coal Geology & Exploration
The coal seams of Leping Formation in Junlian area are high-rank coal reservoir with low porosity and low permeability. The gas production of some coalbed methane wells decreases rapidly in the production process, which seriously restricts the benefit development of coalbed methane wells. Combined with the production data such as drainage, hydrochemistry and pump inspection, this paper analyzes the reasons for the decline of gas production. The main reasons for the decline are coal scaling and coal fines blockage. Targeted measures such as acid pickling, hydraulic shock, plasma pulse and water injection are carried out to remove the blockage. The …
Mine Water Inflow Modes And Scientific Design Of Drainage Boreholes In Roof Confined Aquifer Of Coal Seam, Hu Weiyue, Ji Yadong, Huang Huan
Mine Water Inflow Modes And Scientific Design Of Drainage Boreholes In Roof Confined Aquifer Of Coal Seam, Hu Weiyue, Ji Yadong, Huang Huan
Coal Geology & Exploration
Aiming at the uncertainty of mine water inflow mode, this paper analyzes the spatiotemporal variation characteristics of mine water inflow at first, and get a conclusion that the mine water is composed of static storage and dynamic recharge. And the static storage is mainly affected by weighting interval, the aquifer thickness of caving and fracture zone height and specific yield; the dynamic recharge is mainly affected by caving and fracture zone height and specific yield, hydraulic gradient in permeable flow field and discharge section area. According to the spatial relationships between water conducted fissure and roof aquifer of coal seam, …
Optimization Of Regional Advanced Coal Floor Water Hazard Prevention And Control Technology And Its Application, Zheng Shitian, Ma Hewen, Ji Yadong
Optimization Of Regional Advanced Coal Floor Water Hazard Prevention And Control Technology And Its Application, Zheng Shitian, Ma Hewen, Ji Yadong
Coal Geology & Exploration
In order to optimize the grouting process, improve the effect of the technology, and promote its application, this paper presents an investigation on the application of the regional advanced coal floor water hazard prevention and control technology in Huaibei mining area. The investigation shows that the pressure control in low pressure diffusion and medium pressure strengthening stages plays a major role in controlling the total grouting volume, which directly affects the limestone aquifer reformation. The prediction formula for grouting volume for strata with different karst fractures can provide guidance to the grouting engineering design. In addition, the horizontal layout method …
Experimental Study On Visual System For Water-Blocking Process Of Hydrodynamic Roadway By Aggregate Pouring In Water Inrush Mine, Mou Lin
Coal Geology & Exploration
Blocking water of hydrodynamic roadway by aggregate pouring in water inrush mines is an important method for mine rescue. To study its mechanism, the experimental platform of similar simulation test was established based on such factors as water head height, flow rate, roadway size, inclination angle, roughness, aggregate particle size and perfusion speed. Based on the platform, single-hole and multi-hole pouring tests were carried out to analyze the movement and accumulation law of aggregate in hydrodynamic pathway. The results are as follows. Firstly, the accumulation body has the characteristics of migration and growth to the downstream during the normal pouring …
Statistical Regularity Of Physical And Mechanical Indexes Of Secondary Red Clay In Chenggong District, Kunming, Gao Haiyan, Zhang Jiaming
Statistical Regularity Of Physical And Mechanical Indexes Of Secondary Red Clay In Chenggong District, Kunming, Gao Haiyan, Zhang Jiaming
Coal Geology & Exploration
In order to analyze the statistical regularity of physical and mechanical indexes of secondary red clay in Chenggong District, Kunming, the index data of 275 groups of secondary red clay samples from 69 geotechnical investigation boreholes in Wujiaying area of Chenggong are taken as the research object. Based on the statistical analysis principle, the variation range, average value, standard deviation, coefficient of variation of 13 indexes and the correlation between indexes and depth are analyzed by SPSS statistical analysis software, and the physical and mechanical properties of secondary red clay are summarized. Then, the linear empirical formula between indexes is …
Performance Deterioration Law Of Retarded Cement Slurry And Its Mixed Slurry In Freezing Borehole Mud Replacement, Li Qiang, Wang Yansen, Wang Chunlin, Xu Shengji, Fan Zhiqiang
Performance Deterioration Law Of Retarded Cement Slurry And Its Mixed Slurry In Freezing Borehole Mud Replacement, Li Qiang, Wang Yansen, Wang Chunlin, Xu Shengji, Fan Zhiqiang
Coal Geology & Exploration
The mud replacement of freezing hole has become a necessary part of freezing shaft sinking in rock strata, but in the lowering process, the freezing pipe is prone to excessive slurry viscosity resistance, and even be locked, leading to borehole failure. In order to deeply understand the performance deterioration law of cement slurry and its mixture in deep hole environment, the laboratory tests of retarded cement slurry and mixed slurry are carried out respectively, taking the apparent viscosity as the measurement index and considering the factors such as curing time, temperature, water loss state and volume ratio of mixed slurry. …
Distribution Characteristics And Paleo-Climatic Significance Of Continental Climate-Sensitive Sediments In The Late Cretaceous In China, Bin Xu, Fang Xiang, Shuxia Li
Distribution Characteristics And Paleo-Climatic Significance Of Continental Climate-Sensitive Sediments In The Late Cretaceous In China, Bin Xu, Fang Xiang, Shuxia Li
Coal Geology & Exploration
The Cretaceous is a typical period for studying the greenhouse climate and the earth system interactions, and the world's most extensive terrestrial strata are mainly in East Asia, especially in China. Continental sediments can effectively reflect the paleo-climate change, but the previous studies of the Late Cretaceous paleo-climate, based on the combined characteristics of continental climate-sensitive sediments, were barely found in China. To obtain the Late Cretaceous paleo-climate characteristics of China, the distribution characteristics of different continental climate-sensitive sediment types in the early, middle and Late Cretaceous in China were studied in detail. According to the distribution and combination characteristics …
Blending Interference Noise Separation Method Of Simultaneous Source Seismic Data Based On Multi-T-X Domain Combination, Yu Dai, Huang Dezhi, Sun Yuan, Yang Wenping
Blending Interference Noise Separation Method Of Simultaneous Source Seismic Data Based On Multi-T-X Domain Combination, Yu Dai, Huang Dezhi, Sun Yuan, Yang Wenping
Coal Geology & Exploration
With the increasing application of simultaneous source seismic data acquisition method in seismic oil and gas exploration, many scholars have studied the key technology of simultaneous source seismic data blending interference noise separation. So far, research on methods with higher fidelity is still needed. This article is based on the following assumptions: Normal Moveout Correction(NMO) in simultaneous source seismic data can enhance the linear distribution degree of reflection(especially in Common Middle Point(CMP) gather), and expand the distribution difference of reflection and blending interference noise; single domain separation of blending interference noise only aims at a certain distribution characteristic difference of …
Influence Of Surrounding Rock Changes On The Coal Seam Reflected Wave Under Thin Interbed Condition, Chang Suoliang, Zhang Sheng, Liu Jing, Liu Zuiliang, Chen Qiang, Liu Bo
Influence Of Surrounding Rock Changes On The Coal Seam Reflected Wave Under Thin Interbed Condition, Chang Suoliang, Zhang Sheng, Liu Jing, Liu Zuiliang, Chen Qiang, Liu Bo
Coal Geology & Exploration
In order to study the influence of the changes of surrounding rock on the reflected wave of coal seam under the condition of thin interbeds, the coal-bearing strata in the λ/4 thin layer range in seismic exploration is taken as the research object, and three types of models of surrounding rock lithology, thickness and structure change are established. By Brekhovskikh equation in the theory of thin-bed reflection coefficient spectrum, the influence of surrounding rock changes on the AVO curve, attributes and gathers of coal seams are calculated and summarized. The research results show that the changes of surrounding rock …
Research And Application Of Horizontal Wire-Line Directional Deviation Correction While Drilling, Wu Jinsheng, Huang Xiaolin, Jiang Bing, Zhang Chi, Wu Wanjiong
Research And Application Of Horizontal Wire-Line Directional Deviation Correction While Drilling, Wu Jinsheng, Huang Xiaolin, Jiang Bing, Zhang Chi, Wu Wanjiong
Coal Geology & Exploration
In wire-line core drilling of horizontal holes, the rotation axis of the drilling tool is not in a straight line with its own gravity direction; with the ground hole pressurized, the drilling trajectory will be deviated due to the soft and hard formation or the occurrence of the rock formation. At present, there is no effective way to achieve directional deviation correction while drilling. This paper studies the pushing, fixing and fishing technologies of small-diameter horizontal wire-line directional instruments while drilling. A set of horizontal rope directional drilling tools and directional technology are developed and applied in directional deviation correction …
Friction Law Of Compound Drilling Along The Coal Seam With Super-Long Directional Drilling, Xu Chao, Jiang Lei, Wang Xian, Fang Jun, Chen Pan, Liu Zhi
Friction Law Of Compound Drilling Along The Coal Seam With Super-Long Directional Drilling, Xu Chao, Jiang Lei, Wang Xian, Fang Jun, Chen Pan, Liu Zhi
Coal Geology & Exploration
The internal friction is the main factor affecting the drilling rate and drilling efficiency in super-long directional drilling in coal mines. In order to meet the objective demand of gas drainage mode in big panels, the friction and its influence law in drilling process are studied. To provide a basis for the selection of friction reduction process parameters of compound drilling along coal seam with super-long directional drilling, the drill string motion characteristics and stress state under the condition of near-horizontal compound drilling in the coal mine are analyzed. With certain conditional assumptions, the mechanical models of axial frictional resistance …
Design And Application Of Pdc Bit For Large Diameter Directional Drilling Of Coal Seam Roof With Double Stage And Double Speed, Gao Xiaoliang, Ju Pei, Zhao Jianguo
Design And Application Of Pdc Bit For Large Diameter Directional Drilling Of Coal Seam Roof With Double Stage And Double Speed, Gao Xiaoliang, Ju Pei, Zhao Jianguo
Coal Geology & Exploration
The development of large diameter directional drilling technology has provided technical support for the extraction of gas in the upper corner of the goaf by "replacing roadway with borehole". At present, conventional large-diameter drilling mainly adopts the step-by-step hole-forming method, which solves the problem of insufficient power of large-diameter drilling equipment in underground coal mines. However, step-by-step reaming requires multiple times of lifting and lowering, long auxiliary time and intensive labor of the workers. In order to improve the drilling efficiency of large-diameter holes in the coal roof, a double stage drilling process with two speeds was developed. The process …