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2019

Oil, Gas, and Energy

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Articles 31 - 60 of 457

Full-Text Articles in Engineering

Supporting Technology Of Roadway Crossing Fractured Zone Of Fault Under Dynamic And Static Load, Song Weihua, Di Chunlei, Deng Zhaorui Dec 2019

Supporting Technology Of Roadway Crossing Fractured Zone Of Fault Under Dynamic And Static Load, Song Weihua, Di Chunlei, Deng Zhaorui

Coal Geology & Exploration

The gateway 5303 encountered multiple normal faults during the driving in Changping mine of Jinmei Group. For the purpose that the gateway can pass through the faults safely and rapidly and ensure applicative methods and scope of supporting. So based on the principle of maximum principal stress and fracture damage mechanics of rock, the paper analyzes the crushing mechanism of the normal fault zone under dynamic and static load from macroscopic and microscopic perspectives. Then, the plastic failure model of fault zone was established, the normal fault sliding mechanism and supporting theory were combined to derive the expression of the …


Fault Identification Technology Of Ant Attribute Optimization, Li Hongwei, Bai Xuelian, Cui Jingbin, Wan Zhonghong, Yuan Shihong, Chu Wanchang Dec 2019

Fault Identification Technology Of Ant Attribute Optimization, Li Hongwei, Bai Xuelian, Cui Jingbin, Wan Zhonghong, Yuan Shihong, Chu Wanchang

Coal Geology & Exploration

In the field of seismic geological exploration, the ant attributes is more and more widely used for rapid identification of fault system, and in the process of practical application, ant attributes based on 3D seismic data extraction are displayed either along strata slice(plan) or in section, the features of fault system and distribution characteristics of seismic events is not corresponding to the actual situation, the application effect is poorer, fault interpretation work is given priority to with manual interpretation backbone profile, unable to realize fault automatic tracking. In view of this widespread situation, this paper studies and analyzes the actual …


Application Of High Precision Gravity Survey In Detecting Mined-Out Areas Of Fushun Coal Mine, Huan Hengfei, Gao Tie, Zhao Haiqing, Zhao Weijun, Guo Canwen, Shi Bin Dec 2019

Application Of High Precision Gravity Survey In Detecting Mined-Out Areas Of Fushun Coal Mine, Huan Hengfei, Gao Tie, Zhao Haiqing, Zhao Weijun, Guo Canwen, Shi Bin

Coal Geology & Exploration

In order to find out the location, depth and distribution range of the mined-out areas in Fushun coal mine, and comprehensively considering the factors affecting the geophysical methods in the cities, the method of high-precision gravity survey was firstly used to study the mined-out areas in the area. Firstly, by analyzing the physical differences of the mined-out areas, a theoretical model was established for forward calculation and preliminarily studied on applicability of the gravity method. Then, a large-scale work of high-precision gravity survey was arranged in the study area, and through potential field separation,3D apparent density inversion and boundary identification …


Analysis Of Factors Affecting The Automatic High-Frequency Induction Brazing Strength Of Pdc, Dai Yongbo Dec 2019

Analysis Of Factors Affecting The Automatic High-Frequency Induction Brazing Strength Of Pdc, Dai Yongbo

Coal Geology & Exploration

With the development of automation and intelligentization in manufacturing industry, the research on PDC bit brazing automation is one of the key development directions of bit production technology. In order to study the influencing factors and adaptation methods of welding strength in PDC automatic brazing process, PDC high frequency induction welding and shear strength comparison test were carried out by using PDC and alloy pillar as the base material through special tooling and test conditions. Combined with the shear strength experiment and the morphology of brazing surface of PDC high-frequency induction brazing, the effect of brazing filler alloys, fluxes, surface …


Synthesis And Connection Of Iridium Hydrogen Evolution Catalyst To Chlorella Vulgaris Photosystem I For Light-Driven Hydrogen Evolution, Anna Ramirez Dec 2019

Synthesis And Connection Of Iridium Hydrogen Evolution Catalyst To Chlorella Vulgaris Photosystem I For Light-Driven Hydrogen Evolution, Anna Ramirez

Honors Program Theses and Projects

Hydrogen gas has been shown to be a promising energy source as options other than fossil fuels are being looked at in the face of anthropogenic climate change. It is known that anthropogenic climate change is caused by the production of greenhouse gases being let into the atmosphere, specifically a common reason for this is the burning of fossil fuels for energy. The overall goal of this project is to design a biochemical hybrid system that will be used to make H 2 gas and does not require the use of fossil fuels. Burning hydrogen as fuel produces only water …


Optimizing Hydrogen Sulfide Removal And Biogas Production Using The Water Wash Method, Brian Leightner Dec 2019

Optimizing Hydrogen Sulfide Removal And Biogas Production Using The Water Wash Method, Brian Leightner

Theses and Dissertations

Biogas forms from decomposing organic material in agricultural digesters, landfills, and wastewater treatment plant digesters. Biogas is mostly composed of methane, and can be used as a carbon-based fuel. Microorganisms that consume organics in these waste streams also produce hydrogen sulfide (H2S) as part of the biogas, in varying trace amounts. H2S is corrosive to engines and pipes for machinery, a human health hazard when inhaled, and an aquatic hazard when dissolved in water. Water washing is an absorption process that dissolves hydrogen sulfide and other water soluble compounds in this process and carries it away from the gas, thereby …


Fabrication And Characterization Of Electrical Energy Storage And Harvesting Energy Devices Using Gel Electrolytes, Belqasem Aljafari Nov 2019

Fabrication And Characterization Of Electrical Energy Storage And Harvesting Energy Devices Using Gel Electrolytes, Belqasem Aljafari

USF Tampa Graduate Theses and Dissertations

Redox-active materials in the bulk of gel electrolytes are unquestionably holding the primary roles in developing energy harvesting and storage technology. Both technologies are necessary in order to cope with the current challenges of the environmental crises of global warming and finite non-renewable sources while the demand for energy modern societies have been speedily increased. One of the most challenges of making a hybrid device of energy conversion and storage is the cost of the fabrication process. Therefore, gel electrolyte-based materials with redox-active properties can potentially be a promising solution to improve the performance of electrochemical and photoelectrochemical devices for …


Modeling Of Buildings With Electrochromic Windows And Thermochromic Roofs, Hua-Ting Kao Oct 2019

Modeling Of Buildings With Electrochromic Windows And Thermochromic Roofs, Hua-Ting Kao

USF Tampa Graduate Theses and Dissertations

Air conditioning and heating have increased substantially during the past two decades. According to a survey, buildings consume about 73% of the total electricity in the United States, accounting for 41% of all other energy in the world. At the same time, building skin technologies are constantly improving. Electrochromic and thermochromic are two exciting new technologies that can help reduce the energy consumption of a building. The purpose of this work is to increase our understanding of how much the use of electrochromic (EC) and thermochromic (TC) technologies can reduce the energy consumption of residential and commercial buildings in two …


Stability Of Cement-Based Grouting Slurry And Test Of Its Bleeding Law, Xu Bin, Dong Shuning, Xu Lulu, Zhou Yan, Chen Junjun, Dai Zhenxue, Wang Hao Oct 2019

Stability Of Cement-Based Grouting Slurry And Test Of Its Bleeding Law, Xu Bin, Dong Shuning, Xu Lulu, Zhou Yan, Chen Junjun, Dai Zhenxue, Wang Hao

Coal Geology & Exploration

To better understand the stability performance and bleeding property of cement-based grouting slurry, a new test device was improved to get the separated-water thickness value of slurry samples at every time, and these samples were made and sorted according to the certain proportion of the water-solid ratio(0.6:1 to 3:1), fly ash content(0-90%) and sodium silicate content(0-12%). The growth theory for separated-water thickness was introduced, and the growth curves for all formulations were plotted. The slurry stability measurement method was classified, and the equivalence relation between the direct measurement method of slurry stability and the indirect measurement method was verified. The …


Micro Ct-Based Meticulous Characterization Of Porosity Evolution Of Coal In The Process Of Biodegradation, Dong Zhiwei, Guo Hongyu, Xia Daping, Liu Xile, Bai Yang, Zhao Guojun Oct 2019

Micro Ct-Based Meticulous Characterization Of Porosity Evolution Of Coal In The Process Of Biodegradation, Dong Zhiwei, Guo Hongyu, Xia Daping, Liu Xile, Bai Yang, Zhao Guojun

Coal Geology & Exploration

To explore the bio-permeability enhancing effect via methanogen treatment on different rank coals after anaerobic fermentation, micro-CT was used to analyze the change characteristics of pore structure of coal before and after biodegradation. At the same time, the adsorption characteristics of methanogens on the coal surface after anaerobic biodegradation were observed by scanning electron microscopy to analyze the reasons for the effect difference of biological transformation of different rank coals. The results show that the porosity and total throat length of the coal samples biodegraded increase and the connectivity of the pores is enhanced, it is indicated that coal samples …


Reasons Of Low Yield And Stimulation Measures For Vertical Cbm Wells In High-Rank Coal, Jia Huimin, Hu Qiujia, Qi Kongjun, Liu Chunchun, Fan Bin, He Jun Oct 2019

Reasons Of Low Yield And Stimulation Measures For Vertical Cbm Wells In High-Rank Coal, Jia Huimin, Hu Qiujia, Qi Kongjun, Liu Chunchun, Fan Bin, He Jun

Coal Geology & Exploration

The CBM production is usually low and development effect is poor in China, which are mainly due to the poor adaptability of the stimulation measures to the geological conditions. This article, based on the low-yield reasons for vertical CBM wells in Zhengzhuang block in southern Qinshui basin, puts forth corresponding stimulation measures, analyzes the mechanism and the geological adaptability, optimizes the parameters of specific stimulation measures and carries out pilot test. The research and practices show that in deeply buried area, fractures are difficult to form, and re-fracturing technology can make the fracture turn and increase the crack length, which …


Development And Test Of Self-Adjusting Deflected Wellhead Sealing Device For Coalbed Methane Wells, Pang Tao Oct 2019

Development And Test Of Self-Adjusting Deflected Wellhead Sealing Device For Coalbed Methane Wells, Pang Tao

Coal Geology & Exploration

In order to solve the problem of fluid and gas leakage in coal seam gas well, a self-adjusting deflected wellhead sealing device suitable for coal seam gas wells is developed. The device consists of three parts:Smooth rod sealing box, self-adjusting deflected part and lower sub. The self-adjusting deflected part is a smart combination of universal joint and high pressure flexible rubber tube, which makes the sealing box and the polished rod always keep good concentricity. Practical application shows that this kind of polished rod sealing device has reliable sealing performance, simple structure and the prospect of popularization and application.


Influence Of The Freezing-Thawing Cycles On Soil-Water Characteristics Of Soil In Open-Pit Mine Dumping Sites, Wang Xuedong, Li Shiyu, Sun Yanfeng, Ye Guo Oct 2019

Influence Of The Freezing-Thawing Cycles On Soil-Water Characteristics Of Soil In Open-Pit Mine Dumping Sites, Wang Xuedong, Li Shiyu, Sun Yanfeng, Ye Guo

Coal Geology & Exploration

In order to study the unsaturated soil-water characteristics of soil under freezing-thawing cycles, the soil in Yuanbaoshan open-pit mine dumping site was selected as the research object. The variation of matrix suction and structure of soil under different water content after different freezing-thawing cycles was studied. The results show that during the same freezing-thawing cycles, the matrix suction increases with the decrease of water content, and the range increases gradually. The soil-water characteristic curve can be divided into sensitive stage, sub-sensitive stage and insensitive stage. With the increase of freezing-thawing cycles, the curvature of soil-water characteristic curve increases first and …


Test Of The Influence Of Dynamic Water Grouting Diffusion Radius Of Fractures In Rock, Gu Shuancheng, Sun Guanlin, Su Peili, Li Jinhua Oct 2019

Test Of The Influence Of Dynamic Water Grouting Diffusion Radius Of Fractures In Rock, Gu Shuancheng, Sun Guanlin, Su Peili, Li Jinhua

Coal Geology & Exploration

Water-cement ratio and grouting pressure are the key factors in the design of hydrodynamic grouting. In this paper, based on the self-designed simulated fissure hydrodynamic grouting indoor test platform, the dynamic water grouting test was carried out, the diffusion mode of the slurry in fractures was discussed. The relationship among the diffusion radius of pure cement slurry, the grouting pressure and water-cement ratio was analyzed. The experimental results were verified by computational fluid dynamics software. The results show that the diffusion mode of the slurry is partition diffusion. When the grouting pressure is constant, the diffusion radius is inversely proportional …


Influence Of Loading Rate On The Fracture Characteristics Of Large-Size Specimen, Chen Juntao, Li Ming, Cheng Binbin, Yang Fan, Men Huili, Shao Zhujuan Oct 2019

Influence Of Loading Rate On The Fracture Characteristics Of Large-Size Specimen, Chen Juntao, Li Ming, Cheng Binbin, Yang Fan, Men Huili, Shao Zhujuan

Coal Geology & Exploration

According to the high mining speed of modern mines in China, the fracture characteristics of rock mass under different uniaxial loading rate was systematically analyzed. Based on the geological condition of deep rock mass in Jining area, the optimum mortar composed of 425 Portland cement, sand with particle size less than 2 mm, gypsum, water and high efficient water reducer was used, which had the mechanical properties similar to real rock mass was ascertained. Applying the triaxial rock test system of coupled stress-seepage and PCI-2 real-time monitoring system of AE, the fracture process of specimens of large size under biaxial …


Acquisition Platform Of Frequency Domain Ip Signal, Fu Guohong, Zhang Qianfeng, Cheng Hui, Xie Tiancai Oct 2019

Acquisition Platform Of Frequency Domain Ip Signal, Fu Guohong, Zhang Qianfeng, Cheng Hui, Xie Tiancai

Coal Geology & Exploration

In order to improve the versatility of the induced polarization(IP) signal receiver of traditional frequency domain, a signal acquisition platform was designed, which can acquire and process IP signals of frequency domain such as variable-frequency signals, dual-frequency IP signals, and pseudo-random multi-frequency IP signals and so on. Hardware circuits were established based on STM32 to execute low-pass filtering, program-controlled amplification, analog-to-digital conversion, and data communication. The host computer was developed in LabVIEW to achieve parameter settings, digital filtering, spectrum analysis, amplitude measurement and calculation to obtain target parameters such as PFE, and has waveform display and playback, data storage and …


Calibration And Experiment Of Mine Electromagnetic Lwd Gamma Logging Tool, Wang Xiaolong, Jiang Bici, Wang Kaibin Oct 2019

Calibration And Experiment Of Mine Electromagnetic Lwd Gamma Logging Tool, Wang Xiaolong, Jiang Bici, Wang Kaibin

Coal Geology & Exploration

In order to effectively identify coal seam, roof and floor, mine electromagnetic LWD gamma logging tool was developed for directional drilling in coal mine. The calibration coefficient of the instrument can be obtained by natural gamma logging scale, and various measurement curves of mine electromagnetic LWD gamma logging tool can be obtained by standard well test and crossing borehole test in coal mine. Through comparing with the gamma curve of standard well and analyzing the geological data of the crossing borehole, the measurement result accuracy of mine electromagnetic LWD gamma logging tool is verified. The application test in underground coal …


The Influence Of Grounding Grid On Electromagnetic Detection Of Goaf, Xu Xing, Weng Ling, Li Shiqiang, Liu Guoqiang Oct 2019

The Influence Of Grounding Grid On Electromagnetic Detection Of Goaf, Xu Xing, Weng Ling, Li Shiqiang, Liu Guoqiang

Coal Geology & Exploration

The existence of underground goaf can easily cause tilting and settlement of power towers, which is a major hidden factor in the safe and stable operation of power grid. To detect the mine goaf under the power transmission corridor is of great significance. When there is a grounding grid in the detection area, the grounding grid will have certain influence on the measured value. In this paper, the detection of mine goaf in the presence of a grounding grid is presented. Based on the theoretical analysis, the mathematical model is built, and the simulation model is conducted. The influence of …


Table Of Contents, The Editors Oct 2019

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.


Trilinear Chart Classification Method Of Mine Water Hazard Type Based On Factors Of Water Recharge, Hu Weiyue, Zhao Chunhu Oct 2019

Trilinear Chart Classification Method Of Mine Water Hazard Type Based On Factors Of Water Recharge, Hu Weiyue, Zhao Chunhu

Coal Geology & Exploration

The results of the classification of hydrogeological types in coal mines are relatively inadequate to reflect the characteristics of water hazards such as water sources and water inrush channels. It is not very instructive to carry out water control work in coal mines starting from the basic elements of mine water hazard formation, this paper analyses the characteristics and harm degree of mine water hazard under different types of mine water sources, water inrush channels and their combination conditions, the water inrush source can be divided into 4 types according to its water-rich degree and supply capacity:weak supply of slow …


Fractal Theory-Based Investigation Of The Optimal Interval Of Minimum Pore Radius Of Sandstone, Xu Lulu, Dong Shuning, Dai Zhenxue, Xu Bin, Yin Shangxian, Zhou Yan, Chen Junjun Oct 2019

Fractal Theory-Based Investigation Of The Optimal Interval Of Minimum Pore Radius Of Sandstone, Xu Lulu, Dong Shuning, Dai Zhenxue, Xu Bin, Yin Shangxian, Zhou Yan, Chen Junjun

Coal Geology & Exploration

Permeability is a main parameter for evaluation of water conductivity of porous media, and it is a macroscopic feature of micro-pore structure of water-conducting media. To obtain the geometry parameters of microscopic pores, we performed scanning electron microscopy(SEM) on sandstone samples. The image processing techniques were also applied in calculation of different statistical parameters(e.g., fractal dimensions) and geometrical parameters. Then, fractal theory was introduced to investigate the influence of micro pore structure on permeability. At the same time, the minimum pore radius rmin interval acting on the seepage was obtained by the measured permeability values. This interval can be …


Analytical Solution For Surrounding Rock Of Circular Roadway Based On Generalized Smp Criterion Considering Seepage And Dilatancy, Pan Jiliang, Ren Fenhua Oct 2019

Analytical Solution For Surrounding Rock Of Circular Roadway Based On Generalized Smp Criterion Considering Seepage And Dilatancy, Pan Jiliang, Ren Fenhua

Coal Geology & Exploration

Based on the generalized spatially mobilized plane(SMP) criterion, considering intermediate principal stress, pore water pressure and dilatancy characteristics of surrounding rock, an ideal elastic-plastic model of roadway surrounding rock is established. According to the elastic-plastic theory, the unified analytical solutions of stress field, displacement field and radius of plastic zone under seepage flow are obtained. Then, the stress distribution of surrounding rock and the radius of plastic zone calculated by SMP criterion are compared with those calculated by Mohr-Coulomb(M-C) criterion, and the influencing factors such as pore water pressure and dilatancy angle of surrounding rock are analyzed. It is shown …


Experimental Study Of Three-Component Down-Hole Tem For Detecting Water-Filled Goaf, Yao Weihua, Wang Peng, Li Mingxing, Su Chao, Cheng Siyuan Oct 2019

Experimental Study Of Three-Component Down-Hole Tem For Detecting Water-Filled Goaf, Yao Weihua, Wang Peng, Li Mingxing, Su Chao, Cheng Siyuan

Coal Geology & Exploration

The borehole geophysical prospecting method is a research hotspot in recent years. Considering that the down-hole transient electromagnetic method used in metal mines has the characteristics of long radial detection distance and less susceptible to surface electromagnetic interference, it is applied to the exploration of water-filled goaf in coal mines. Three-dimensional finite-difference time-domain(FDTD) algorithm is used to simulate the total field response and abnormal response of the goaf model with different orientations of boreholes. The total field three-component could reflect the water-filled goaf obviously, and the abnormal field three-component shape combination can distinguish the azimuth of the abnormal body. Based …


Fractal Characteristics Of Pores And Microfractures Of Coals With Different Structure And Their Effect On Permeability, Ye Zhenni, Hou Enke, Duan Zhonghui, Wen Qiang, Huang Meitao, He Dan Oct 2019

Fractal Characteristics Of Pores And Microfractures Of Coals With Different Structure And Their Effect On Permeability, Ye Zhenni, Hou Enke, Duan Zhonghui, Wen Qiang, Huang Meitao, He Dan

Coal Geology & Exploration

The characteristics of pores and fractures in coal are the basis to study permeability. In this study, the micro-pores and fractures of coal samples with different structure taken from Guojiahe coal mine were analyzed using mercury injection experiment and scanning electron microscope. The micro-pores and fractures of intact coal and cataclastic coal samples were quantitatively analyzed by using Menger sponge and box-counting dimension. The comprehensive fractal dimension was calculated by pore volume weights. Based on fractal theory, the relationship between fractal dimension of coal samples and coal permeability have been discussed. The results show that brittle deformation adds complexity of …


Analysis On The Type Of Reservoir Pressure Drop And Drainage Control Of Coalbed Methane Well In The Southern Block Of Shizhuang, Yi Yongxiang, Tang Shuheng, Zhang Songhang, Yan Xinlu, Wang Kaifeng, Dang Feng Oct 2019

Analysis On The Type Of Reservoir Pressure Drop And Drainage Control Of Coalbed Methane Well In The Southern Block Of Shizhuang, Yi Yongxiang, Tang Shuheng, Zhang Songhang, Yan Xinlu, Wang Kaifeng, Dang Feng

Coal Geology & Exploration

In order to fully understand the reservoir pressure variation characteristics of coalbed methane wells in the southern block of Shizhuang and based on the analysis of reservoir geological parameters and the analysis of actual production data, the reservoir pressures of different types of production wells are analyzed. The specific analysis of the drainage control and reservoir sensitivity effects is also carried out based on the abnormal wells. The results showed that the reservoir lamination of coalbed methane wells in the southern block of Shizhuang can be divided into three types, namely type of rapid pressure drop, type of medium-term stability …


Similar Model Test And Mechanical Analysis Of Fault Structure, Song Yanqi, Wang Shilei, Sun Chuan, Hao Liangjun Oct 2019

Similar Model Test And Mechanical Analysis Of Fault Structure, Song Yanqi, Wang Shilei, Sun Chuan, Hao Liangjun

Coal Geology & Exploration

The pre-existing fault specimens were made to confirm the actual stratum mechanical properties based on the similarity theory. Then the mechanism of failure mode of pre-existing fault was analyzed under the crack tip stress field theory. The results show that with the increase of load, the microcracks develop gradually and propagate, and the propagation path tends to the loading direction. In the process of crack propagation, multiple branch paths are generated, and then the cracks merge with each other to destroy the specimen. The stress field theory can be used to determine the newly generated fracture direction, which is consistent …


Experimental Study On Contact Angle And Pore Characteristics Of Unsaturated Loess, Jing Yanlin, Wang Hao, Tao Chunliang, Yang Lina, Liu Jianwei, Wen Xin Oct 2019

Experimental Study On Contact Angle And Pore Characteristics Of Unsaturated Loess, Jing Yanlin, Wang Hao, Tao Chunliang, Yang Lina, Liu Jianwei, Wen Xin

Coal Geology & Exploration

Contact angle and pore size are important factors affecting soil wettability, permeability and capillarity. In order to further understand the capillary characteristics and permeability of unsaturated loess, the contact angle test and mercury intrusion test of unsaturated loess were carried out. The relationship between pore size and contact angle was analyzed in details. Moreover, the variation of pore and contact angle with depth was discussed. It is found that the contact angle of loess in the dry state is higher than the contact angle of loess in the natural state; as the depth of the formation increases, the contact angle …


A New Instability Criterion Of Double Strength Reduction Method For Slope, Fang Hongwei, Wu Jianxun, Hou Zhenkun Oct 2019

A New Instability Criterion Of Double Strength Reduction Method For Slope, Fang Hongwei, Wu Jianxun, Hou Zhenkun

Coal Geology & Exploration

Based on the slip line field theory(SLFT), a new instability criterion of strength reduction method with double re-duction factors for homogeneous slopes was proposed. It is judged that the slope is in the limit equilibrium state when the slope contour under limit equilibrium state(abbreviated as the critical slope contour) calculated by the SLFT intersects with the slope line at the toe. The critical curve was constructed in the plane of the inverse of the double reduction factors, and the comprehensive safety factor was derived. The slope calculation results show that three relative position relationships between the initial point and the …


The Effect Of Viscoelasticity And Velocity Anisotropy On The Reflections Of A Thin Bed, Chen Benchi, Wang Chao, Chen Changxing, Shi Lei Oct 2019

The Effect Of Viscoelasticity And Velocity Anisotropy On The Reflections Of A Thin Bed, Chen Benchi, Wang Chao, Chen Changxing, Shi Lei

Coal Geology & Exploration

The coal seam is a typical thin bed characterized by much lower elastic impedance than that of the surrounding rock. Coal seam has viscoelasticity and velocity anisotropy and its reflection amplitude changes with frequency. In order to analyze the effect of viscoelasticity and velocity anisotropy on seismic responses of a thin bed, this paper aims at a thin-bed model with strong impedance contrast and simulates seismic responses under three different assumptions, elastic and velocity isotropy, viscoelastic and velocity isotropy, and viscoelastic and velocity anisotropy, through numerical simulation method based on wave equations. Comparison of these seismic reflections shows that the …


Design And Application Of Multi-Section Bundled Bag Wire-Line Coring Drilling Tools, Han Yi, Zhang Shaohe, Bai Rui, Sun Pinghe, Shu Biao, Cao Han, Zhang Xinxin Oct 2019

Design And Application Of Multi-Section Bundled Bag Wire-Line Coring Drilling Tools, Han Yi, Zhang Shaohe, Bai Rui, Sun Pinghe, Shu Biao, Cao Han, Zhang Xinxin

Coal Geology & Exploration

Because the existing conventional wire-line coring drilling tool lacks the water-proof and core-protecting device, the broken core is easily eroded when the core is drilled in a complicated layer such as loose, weak, broken layers and the core is easy to fall off during the lifting process, so that the coring rate and core quality are not up to the design requirements, and even core can not be taken to. In response to the above problems, a bag-type wire-line coring drilling tool was designed. The drill adds a multi-section bundled bag assembly structure to the conventional wire-line coring drilling tool …