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Neural Net Detection Of Seismic Features Related To Gas Hydrates And Free Gas Accumulations On The Northern U.S. Atlantic Margin, Urmi Majumdar, Nathaniel C. Miller, Carolyn D. Ruppel Sep 2022

Neural Net Detection Of Seismic Features Related To Gas Hydrates And Free Gas Accumulations On The Northern U.S. Atlantic Margin, Urmi Majumdar, Nathaniel C. Miller, Carolyn D. Ruppel

United States Geological Survey: Staff Publications

Bottom-simulating reflections (BSRs) that sometimes mark the base of the gas hydrate stability zone in marine sediments are often identified based on the reverse polarity reflections that cut across stratigraphic layering in seismic amplitude data. On the northern U.S. Atlantic margin (USAM) between Cape Hatteras and Hudson Canyon, legacy seismic data have revealed pronounced BSRs south of the deepwater extension of Hudson Canyon and more subtle ones from offshore Delaware south to Cape Hatteras, where the reflections sometimes follow stratigraphic layering. Using high-resolution seismic data acquired during the 2018 Mid-Atlantic Resource Imaging Experiment and a supervised neural net, we identify …


Odu’S Storm Recovery Project Gets Boost From Dominion Energy, News @ Odu Sep 2022

Odu’S Storm Recovery Project Gets Boost From Dominion Energy, News @ Odu

News Items

No abstract provided.


Establishment Of Invasive Black Carp (Mylopharyngodon Piceus) In The Mississippi River Basin: Identifying Sources And Year Classes Contributing To Recruitment, Gregory W. Whitledge, Patrick T. Kroboth, Duane C. Chapman, Quinton E. Phelps, Wes Sleeper, Jennifer Bailey, Jill A. Jenkins Sep 2022

Establishment Of Invasive Black Carp (Mylopharyngodon Piceus) In The Mississippi River Basin: Identifying Sources And Year Classes Contributing To Recruitment, Gregory W. Whitledge, Patrick T. Kroboth, Duane C. Chapman, Quinton E. Phelps, Wes Sleeper, Jennifer Bailey, Jill A. Jenkins

United States Geological Survey: Staff Publications

Black Carp (Mylopharyngodon piceus) was imported to the USA to control aquaculture pond snails. This species has escaped captivity and occurs in parts of the Mississippi River, several tributaries, and floodplain lakes, which is concerning due to potential competition with native fishes and predation on native mussels, many of which are imperiled. However, Black Carp captures have primarily been incidental by commercial fishers, and evidence of reproduction in the wild is limited. The objectives of this study were to assess relative abundance of aquaculture- origin and wild Black Carp using ploidy and otolith stable isotope analysis, identify spatial …


Multi-Omics Responses In Tree Swallow (Tachycineta Bicolor) Nestlings From The Maumee Area Of Concern, Maumee River, Ohio, Chi Yen Tseng, Christine M. Custer, Thomas W. Custer, Paul M. Dummer, Natalie Karouna-Renier, Cole W. Matson Sep 2022

Multi-Omics Responses In Tree Swallow (Tachycineta Bicolor) Nestlings From The Maumee Area Of Concern, Maumee River, Ohio, Chi Yen Tseng, Christine M. Custer, Thomas W. Custer, Paul M. Dummer, Natalie Karouna-Renier, Cole W. Matson

United States Geological Survey: Staff Publications

A multi-omics approach was utilized to identify altered biological responses and functions, and to prioritize contaminants to assess the risks of chemical mixtures in the Maumee Area of Concern (AOC), Maumee River, OH, USA. The Maumee AOC is designated by the United States Environmental Protection Agency as having significant beneficial use impairments, including degradation of fish and wildlife populations, bird or animal deformities or reproduction problems, and loss of fish and wildlife habitat. Tree swallow (Tachycineta bicolor) nestlings were collected at five sites along the Maumee River, which included wastewater treatment plants (WWTPs) and industrial land-use sites. Polychlorinated …


Approval Letter For: Butte Priority Soils Operable Unit (Bpsou) Revised Draft Final Quarterly Operations And Maintenance Report Butte Treatment Lagoons System – Second Quarter 2021 (Dated July 20, 2022), Nikia Greene Sep 2022

Approval Letter For: Butte Priority Soils Operable Unit (Bpsou) Revised Draft Final Quarterly Operations And Maintenance Report Butte Treatment Lagoons System – Second Quarter 2021 (Dated July 20, 2022), Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Approval Letter For: Butte Priority Soils Operable Unit (Bpsou) Revised Draft Final Quarterly Operations And Maintenance Report Butte Treatment Lagoons System – Third Quarter 2021 (Dated July 20, 2022), Nikia Greene Sep 2022

Approval Letter For: Butte Priority Soils Operable Unit (Bpsou) Revised Draft Final Quarterly Operations And Maintenance Report Butte Treatment Lagoons System – Third Quarter 2021 (Dated July 20, 2022), Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Draft Final Insufficiently Reclaimed Sites - Field Sampling Plan (Fsp) Bres No. 38 – Sister Dump (Dated June 16, 2022), Nikia Greene Sep 2022

Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Draft Final Insufficiently Reclaimed Sites - Field Sampling Plan (Fsp) Bres No. 38 – Sister Dump (Dated June 16, 2022), Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Approval Letter For The Request For Change (Rfc) To The Butte Priority Soils Operable Unit (Bpsou) Request For Change (Rfc) No. 1 To The Final 2022 Insufficiently Reclaimed Sites Quality Assurance Project Plan (Qapp) (Dated August 31, 2022), Nikia Greene Sep 2022

Approval Letter For The Request For Change (Rfc) To The Butte Priority Soils Operable Unit (Bpsou) Request For Change (Rfc) No. 1 To The Final 2022 Insufficiently Reclaimed Sites Quality Assurance Project Plan (Qapp) (Dated August 31, 2022), Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Revised Draft Final Insufficiently Reclaimed Sites – Field Sampling Plan (Fsp) Bres No. 8 – Belle Of Butte (Dated August 2, 2022), Nikia Greene Sep 2022

Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Revised Draft Final Insufficiently Reclaimed Sites – Field Sampling Plan (Fsp) Bres No. 8 – Belle Of Butte (Dated August 2, 2022), Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Concurrence And Comments On: Sd Response To The Agencies Proposed Raar Path Forward Letter, Dated March 28, 2022 And Pilot Project Annual Update Letter, Dated July 1, 2022, Nikia Greene Sep 2022

Concurrence And Comments On: Sd Response To The Agencies Proposed Raar Path Forward Letter, Dated March 28, 2022 And Pilot Project Annual Update Letter, Dated July 1, 2022, Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Coal Measures Superimposed Gas Reservoir And Its Exploration And Development Technology Modes, Sang Shuxun, Zheng Sijian, Yi Tongsheng, Zhao Fuping, Han Sijie, Jia Jinlong, Zhou Xiaozhi Sep 2022

Coal Measures Superimposed Gas Reservoir And Its Exploration And Development Technology Modes, Sang Shuxun, Zheng Sijian, Yi Tongsheng, Zhao Fuping, Han Sijie, Jia Jinlong, Zhou Xiaozhi

Coal Geology & Exploration

Coal measures superimposed gas reservoir is a key reservoir type of coal-measure gas in coal bearing formation. The discovery, exploration and development practice of coal measures superimposed gas reservoirs in China have opened up a new chapter for the coal-measure gas exploration. In this study, the concept, main types, development characteristics and occurrence distribution of coal measures superimposed gas reservoir are proposed and expounded. The formation prerequisite, accumulation process and reservoir forming mechanism of coal measure superimposed gas reservoir are analyzed. Specifically, the geological suitability exploration and development technology modes of two typical coal measures superimposed gas reservoirs are emphatically …


Typical Coalbed Methane (Cbm) Enrichment And Production Modes Under The Control Of Regional Structure And Evolution, Ju Yiwen, Qiao Peng, Wei Mingming, Li Xin, Xu Fengyin, Feng Guorui, Li Yong, Wu Caifang, Cao Yunxing, Li Guofu, Han Yuming, Li Zhen, Lu Zhigang, Jiang Lei Sep 2022

Typical Coalbed Methane (Cbm) Enrichment And Production Modes Under The Control Of Regional Structure And Evolution, Ju Yiwen, Qiao Peng, Wei Mingming, Li Xin, Xu Fengyin, Feng Guorui, Li Yong, Wu Caifang, Cao Yunxing, Li Guofu, Han Yuming, Li Zhen, Lu Zhigang, Jiang Lei

Coal Geology & Exploration

Coalbed methane (CBM) exploration and development is of great significance to optimize China’s energy structure and cope with coal mine disasters and ecological environment problems. In this paper, combined with regional structure and evolution and CBM geological conditions, the enrichment and recovery modes of CBM are innovatively divided into four categories: simple structural fracture system, fold system (shallower synclinal shaft, fold limb, secondary structural high position), thrust system (fault-thrust-fold belt, high-steep thrust structure) and structural superposition system. Among them, simple structural fracture system mode is often encountered in the areas with relatively stable structure, where the CBM is mainly derived …


Application And Improvement Directions Of Rodless Drainage Technology In Coalbed Methane Wells: A Case Study From East Margin Of Ordos Basin, Ma Wentao, Liu Yinhua, Wu Jianjun, Wang Yubin, Wang Chengwang, Xu Wanyong Sep 2022

Application And Improvement Directions Of Rodless Drainage Technology In Coalbed Methane Wells: A Case Study From East Margin Of Ordos Basin, Ma Wentao, Liu Yinhua, Wu Jianjun, Wang Yubin, Wang Chengwang, Xu Wanyong

Coal Geology & Exploration

The eastern margin of Ordos Basin has a huge amount of coalbed methane resources, and has become one of the main coalbed methane producing areas in China. Since the development of the block, hydraulic rodless pump, hydraulic jet pump, electric submersible pump and diaphragm pump drainage and production process tests have been carried out for highly deviated wells and horizontal wells in medium shallow coal seam. During production, it is found that the above four types of rodless drainage and production processes have the advantages of effectively avoiding eccentric wear of pipes and rods in highly deviated wells and horizontal …


Development Characteristics And Enlightenment Of Eagle Ford Deep Shale Gas Reservoirs In North America, Yu Rongze, Wang Chenghao, Zhang Xiaowei, Hu Zhiming, Sun Yuping, Guo Wei, Duan Xianggang, Wang Meizhu Sep 2022

Development Characteristics And Enlightenment Of Eagle Ford Deep Shale Gas Reservoirs In North America, Yu Rongze, Wang Chenghao, Zhang Xiaowei, Hu Zhiming, Sun Yuping, Guo Wei, Duan Xianggang, Wang Meizhu

Coal Geology & Exploration

The large-scale development of shale gas with a buried depth of less than 3 500 m within the overpressure Wufeng-Longmaxi Formation has been realized in Sichuan Basin, and the effective development of shale gas resources with a buried depth of 3 500-4 000 m is being explored currently. Eagle Ford is an emerging deep shale oil & gas reservoir, which is comparable to the domestic medium-deep development regions and deep exploration regions, and its development technology policy and learning curve are available for reference. The parameters of drilling, fracturing, production and cost of 6 223 wells are analyzed in the …


Key Technology And Engineering Demonstration For Cascade Utilization Of Gas In Key Coal Mining Areas Of Shanxi Province, China, Li Guofu, Li Chao, Huo Chunxiu, Yan Zhiming, Zhang Diankun, Wang Chaoshuai, Wang Zheng Sep 2022

Key Technology And Engineering Demonstration For Cascade Utilization Of Gas In Key Coal Mining Areas Of Shanxi Province, China, Li Guofu, Li Chao, Huo Chunxiu, Yan Zhiming, Zhang Diankun, Wang Chaoshuai, Wang Zheng

Coal Geology & Exploration

The key coal mining areas of Shanxi Province, including Jincheng, Yangquan, Xishan, Fenxi and Lu’an, are the main implementation sites of the “13th Five-Year” national science and technology major project “Demonstration Project of Coordinated Development of Coalbed Methane and Coal in Key Coal Mining Areas of Shanxi”. Relying on the high-end platform of the national science and technology major project, a series of technologies for cascade utilization of coal mine gas have been developed and demonstrated to guide the enhancement of gas drainage and utilization from 6.02 billion m3 and 2.23 billion m3 in 2015 to 6.403 billion …


Reservoir Forming Characteristics And Favorable Area Evaluation Of Deep Coalbed Methane In Daning-Jixian Block, Li Shuguang, Wang Chengwang, Wang Hongna, Wang Yubin, Xu Fengyin, Guo Zhidong, Liu Xinwei Sep 2022

Reservoir Forming Characteristics And Favorable Area Evaluation Of Deep Coalbed Methane In Daning-Jixian Block, Li Shuguang, Wang Chengwang, Wang Hongna, Wang Yubin, Xu Fengyin, Guo Zhidong, Liu Xinwei

Coal Geology & Exploration

The No.8 coal with a buried depth of more than 2 000 m of Lower Permian Taiyuan Formation in Daning-Jixian block, eastern margin of Ordos Basin is the first deep CBM field with an output of 100 billion m3 in China, but the reservoir forming characteristics of deep CBM are still unclear. In this paper, geological information, test and production data are synthetically applied to study the characteristics of deep CBM reservoir formation and evaluation of favorable areas. The results show that the deep coal reservoir in the study area is extensively distributed, with large thickness and high degree …


Analysis On Influencing Factors Of Single/Multi-Layer Development Of Coalbed Methane Field: A Case Study Of Baode Block, Zhang Lei, Xu Fengyin, Li Ziling, Zhang Wei, Hou Wei, Zhang Qingfeng, Zhang Wen, Fan Hongbo, Li Yongchen Sep 2022

Analysis On Influencing Factors Of Single/Multi-Layer Development Of Coalbed Methane Field: A Case Study Of Baode Block, Zhang Lei, Xu Fengyin, Li Ziling, Zhang Wei, Hou Wei, Zhang Qingfeng, Zhang Wen, Fan Hongbo, Li Yongchen

Coal Geology & Exploration

Baode Block in the eastern margin of Ordos Basin is the first coalbed methane field of middle-low rank coal with 500 million cubic meters of production capacity constructed and reached in China, and it is also a benchmark in the coalbed methane industry there. During the development of Baode Block, good results are obtained by the commingled development of two sets of main coal layers, which are better than that of single-layer development. However, poor development result is obtained locally in the commingled development of some wells under the same development conditions, which is poorer than that of single-layer development. …


Exploration Of Integrated Technology For Deep Coalbed Methane Drainage In Full Life Cycle: A Case Study Of Daning‒Jixian Block, Zeng Wenting, Ge Tengze, Wang Qian, Pang Bin, Liu Yinhua, Zhang Kang, Yu Lizhu Sep 2022

Exploration Of Integrated Technology For Deep Coalbed Methane Drainage In Full Life Cycle: A Case Study Of Daning‒Jixian Block, Zeng Wenting, Ge Tengze, Wang Qian, Pang Bin, Liu Yinhua, Zhang Kang, Yu Lizhu

Coal Geology & Exploration

The first deep coalbed methane (CBM) field with a depth of more than 2 000 meters in China has been proven in Daning‒Jixian Block on the eastern margin of Ordos Basin, where the deep coal bed has the characteristics of large buried depth, high pressure, high gas content, high gas saturation and low permeability. Besides, the features of early gas occurrence, high gas-liquid ratio and high salinity of produced liquid are shown in the production process. Problems such as corrosion, anti-eccentric wearing, gas locking and pump blocking were encountered in the application of suction pump based lifting system in the …


Co2 Adsorption Of Anthracite With Different Moisture Contents And Its Implications For Geological Storage, Zhang Jinchao, Sang Shuxun, Han Sijie, Zhang Fengbi, Xu Ang, Liu Qishan Sep 2022

Co2 Adsorption Of Anthracite With Different Moisture Contents And Its Implications For Geological Storage, Zhang Jinchao, Sang Shuxun, Han Sijie, Zhang Fengbi, Xu Ang, Liu Qishan

Coal Geology & Exploration

CO2 geological storage in deep coal seams is regarded as an important pathway to achieve “2030 carbon peak and 2060 carbon neutrality goals”. The moisture content in coal seams plays a significant role in the CO2 storage capacity mainly based on CO2 adsorption. In this study, the anthracite from the Qinshui Basin was collected to conduct high-pressure CO2 adsorption isothermal experiments under dry, moisture-equilibrated and moisture-saturated conditions at 45℃. The CO2 excess adsorption curve was corrected by the reduction of CO2 dissolution. The adsorption capacity and adsorption heat were calculated using the modified D-R …


Formation Pressure Calculation Of Tight Sandstone Gas Reservoir Based On Material Balance Inversion Method, Wu Nan, Shi Shi, Zheng Shiqi, Zhao Haoyang, Wang Hongya, Tong Jiangnan Sep 2022

Formation Pressure Calculation Of Tight Sandstone Gas Reservoir Based On Material Balance Inversion Method, Wu Nan, Shi Shi, Zheng Shiqi, Zhao Haoyang, Wang Hongya, Tong Jiangnan

Coal Geology & Exploration

Pressure is the soul of a gas reservoir. Formation pressure is the basis of evaluating gas well productivity and analyzing gas reservoir potential. However, due to data integrity and method applicability limitations, formation pressure in most gas wells cannot be accurately obtained. On the basis of a small amount of pressure monitoring data, the material balance inversion method is proposed by using mathematical inversion thought to evaluate the formation pressure of tight sandstone gas reservoirs. Firstly, the dynamic reserves of gas wells are calculated by fitting the Blasingame chart with the production data of gas wells under pseudo-steady flow. Secondly, …


Reservoir Properties And Gas Production Difference Between No.15 Coal And No.3 Coal In Zhengzhuang Block, Southern Qinshui Basin, Zhang Cong, Li Mengxi, Feng Shuren, Hu Qiujia, Qiao Maopo, Wu Dingquan, Yu Jiasheng, Li Kexin Sep 2022

Reservoir Properties And Gas Production Difference Between No.15 Coal And No.3 Coal In Zhengzhuang Block, Southern Qinshui Basin, Zhang Cong, Li Mengxi, Feng Shuren, Hu Qiujia, Qiao Maopo, Wu Dingquan, Yu Jiasheng, Li Kexin

Coal Geology & Exploration

With the in-depth exploration and development of coalbed methane (CBM), the development differences between different strata in the same region are gradually emerging. Deepening the understanding of reservoir is crucial to formulate development strategies. Taking the Zhengzhuang Block in the southern Qinshui Basin as an example, in the past, the focus was on the main No.3 coal resources. With the stimulation demand in this block, the CBM needs to be gradually recovered in multiple layers. In this paper, the CBM resource of No.15 coal is analyzed. Comparative analysis with well developed No.3 CBM resources is carried to probe into the …


Acid Fracturing Technology Of Deep Cbm Wells And Its Field Test In Daning-Jixian Block, Liu Changsong, Zhao Haifeng, Chen Shuai, Zhen Huaibin, Wang Chengwang Sep 2022

Acid Fracturing Technology Of Deep Cbm Wells And Its Field Test In Daning-Jixian Block, Liu Changsong, Zhao Haifeng, Chen Shuai, Zhen Huaibin, Wang Chengwang

Coal Geology & Exploration

There are abundant deep coalbed methane resources in China, but the coupling problem of coal reservoir reconstruction technology and deep geological quality conditions needs to be solved urgently. With Daning-Jixian Block as the geological background, the feasibility of volumetric fracturing is evaluated from the perspective of rock mechanical parameters of the No.8 coal seam in a deep layer of the block, and verified by the indoor triaxial acid fracturing model experiment, in order to explore the coal reservoir reconstruction technology under deep geological conditions. Based on the above basic research, the volume acid fracturing technology characterized by high displacement, low …


Practice And Understanding Of Coalbed Methane Co-Production In Zhijin Area, Guizhou, Li Jiaxin, Chen Zhenlong, Guo Tao Sep 2022

Practice And Understanding Of Coalbed Methane Co-Production In Zhijin Area, Guizhou, Li Jiaxin, Chen Zhenlong, Guo Tao

Coal Geology & Exploration

Guizhou Province is a typical area where thin-to-medium thick coalbeds are developed, where the resource endowment characteristics, including multiple coalbeds, small thickness, low permeability, high in-situ stress and multi-layer superposition of pressure system, lead to the difficulties in localization of the mainstream technologies at home and abroad for the development of coalbed methane (CBM) and the utilization of CBM resources. The particularity of these geological characteristics of the multiple and thin CBM determines the obvious selectivity of technologies for its development, and thus the co-production of multiple coalbeds becomes the essential method for effective development and utilization of CBM resources …


Lithofacies And Sedimentary Environment Evolution Of The Shan2 3 Sub-Member Transitional Shale Of The Shanxi Formation In The Daning-Jixian Area, Eastern Ordos Basin, Sun Yue, Jiang Yuqiang, Xiong Xianyue, Li Xingtao, Li Shuxin, Qiu Zhen, Sun Xiongwei Sep 2022

Lithofacies And Sedimentary Environment Evolution Of The Shan2 3 Sub-Member Transitional Shale Of The Shanxi Formation In The Daning-Jixian Area, Eastern Ordos Basin, Sun Yue, Jiang Yuqiang, Xiong Xianyue, Li Xingtao, Li Shuxin, Qiu Zhen, Sun Xiongwei

Coal Geology & Exploration

The Shan2 3 Sub-member transitional facies shale of the Permian Shanxi Formation in the eastern margin of the Ordos Basin is a crucial target for future unconventional oil and gas exploration. Based on field outcrop observation, core description and thin-section identification, combined with X-ray diffraction, trace elements test and other analyses, four types of shale lithofacies were identified, including siliceous, siliceous-argillaceous, calcareous-siliceous (or siliceous-calcareous) and argillaceous lithofacies. The petrological characteristics and geochemical indicators show that the depositional environment of the Shan2 3 Sub-member inherited the epicontinental sea pattern with relatively gentle topography of the late Taiyuan Epoch. The …


Stable-Production Period Prediction Method And Application In High-Rank Coalbed Methane Wells:A Case Study Of Fanzhuang-Zhengzhuang Block In Southern Qinshui Basin, Hu Qiujia, Jia Huimin, Zhang Cong, Fan Bin, Mao Chonghao, Zhang Qing Sep 2022

Stable-Production Period Prediction Method And Application In High-Rank Coalbed Methane Wells:A Case Study Of Fanzhuang-Zhengzhuang Block In Southern Qinshui Basin, Hu Qiujia, Jia Huimin, Zhang Cong, Fan Bin, Mao Chonghao, Zhang Qing

Coal Geology & Exploration

The prediction of stable-production period of Coalbed Methane (CBM) wells is of great significance to the prediction of reasonable stable gas rate and optimization of drainage strategy. Based on mass production data of different well types in Fanzhuang-Zhengzhuang Block, southern Qinshui Basin, the basic concepts of stable-production stage and period of CBM wells are clarified, and the empirical formula for the prediction of stable-production period is proposed and its influencing factors are analyzed. The results show that the CBM well keeps stable production by continuously reducing the bottom-hole-flowing pressure JHH, and the stable-production period is the time required for the …


Table Of Contents, The Editors Sep 2022

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.


Stress Sensitivity Characteristics And Control Mechanism Of Different Coal Rank Reservoirs, Sun Fenjin, Yang Jiaosheng, Wang Meizhu, Sun Bin, Zhang Jidong, Zhao Yang, Deng Ze Sep 2022

Stress Sensitivity Characteristics And Control Mechanism Of Different Coal Rank Reservoirs, Sun Fenjin, Yang Jiaosheng, Wang Meizhu, Sun Bin, Zhang Jidong, Zhao Yang, Deng Ze

Coal Geology & Exploration

The stress sensitivity of coal reservoir reduces the permeability, which in turn affects the productivity of coalbed methane (CBM)wells. So how to reduce this effect from stress sensitivity deserves further study in the CBM wells drainage process. To clarify the stress sensitivity characteristic and differences of different rank coal reservoirs, coal samples collected respectively from Fanzhuang block (high rank coal), Baode block (medium rank coal) and Erlian Basin (low rank lignite) were employed in this study. The stress sensitivity experiments of different rank coal samples were systematically carried out during loading and unloading process. Meanwhile, stress sensitivity mechanism was analyzed. …


Optimum Selection Of Favorable Areas For Multi-Layer Cbm Mining And Reservoir Characterstics In North Yunnan And Guizhou Exploration Area, Sun Bin, Tian Wenguang, Yang Zhaobiao, Yang Minfang, Li Cunlei Sep 2022

Optimum Selection Of Favorable Areas For Multi-Layer Cbm Mining And Reservoir Characterstics In North Yunnan And Guizhou Exploration Area, Sun Bin, Tian Wenguang, Yang Zhaobiao, Yang Minfang, Li Cunlei

Coal Geology & Exploration

Due to the abundance of coal-bearing synclines, multiple seams and high gas content, the exploration area in North Yunnan and Guizhou Provinces is an important expansion block in the periphery of Junlian County. Based on a large number of coalfield holes and test wells, the geological conditions of CBM are analyzed, and the optimization and evaluation method of multi-layer favorable area is established, i.e. multi-level fuzzy mathematics plus key indicators. Firstly, the evaluation model is constructed based on hierarchical optimization, and the key indicators are determined as co-mining coefficient, coal structure and gas content. The co-mining coefficient is composed of …


Damage Mechanism Of Cbm Reservoirs And Double-Layered Screen Pipes In The Horizontal Well Completion, Xian Bao'an, Zhang Long, Ha Erheng Tu’Ersong, Yu Peng, Wang Kai, Zhang Yafei, Zhang Yang, Wang Sanshuai, Li Zongyuan Sep 2022

Damage Mechanism Of Cbm Reservoirs And Double-Layered Screen Pipes In The Horizontal Well Completion, Xian Bao'an, Zhang Long, Ha Erheng Tu’Ersong, Yu Peng, Wang Kai, Zhang Yafei, Zhang Yang, Wang Sanshuai, Li Zongyuan

Coal Geology & Exploration

Coal reservoirs have the characteristics of high adsorption, low permeability, easy compression and easy breakage. At the drilling and completing stage of horizontal coalbed methane wells, coal reservoir damage often occurs and leads to a significant reduction in coal seam permeability, thereby resulting in single well production. Through experimental analysis, the solid phase particles in drilling and completion fluids for horizontal well and the solid phase components induced by fluid flow are found to block the micro-fractures in the coal reservoir, and the damage mechanism for coal reservoir is elucidated to the drilling and completion reservoir of the horizontal well …


Construction Concept Of Integrated Geological Engineering Platform For Coalbed Methane, Li Guihong, Zhao Peipei, Wu Xinbo Sep 2022

Construction Concept Of Integrated Geological Engineering Platform For Coalbed Methane, Li Guihong, Zhao Peipei, Wu Xinbo

Coal Geology & Exploration

The production of coalbed methane (CBM) wells in China is generally low, and the CBM geological research is seriously divorced from the engineering, so it is urgent to introduce the idea of geological engineering integration, which is helpful to form a scientific engineering decision. In this paper, the idea of constructing a CBM geological engineering integration platform is proposed, and its business framework and function framework are built. Various professional software tools are integrated, such as Petrel for geological modeling, compass for drilling and completion design, MFrac for fracturing design, and CBM-SIM for reservoir numerical simulation. An integrated shared database …