Geological controls of shale gas accumulation and enrichment mechanism in Lower Cambrian Niutitang Formation of western Hubei, Middle Yangtze, China

作     者：Lulu XU Saipeng HUANG Zaoxue LIU Yaru WEN Xianghui ZHOU Yanlin ZHANG Xiongwei LI Deng WANG Fan LUO Cheng CHEN Lulu XU;Saipeng HUANG;Zaoxue LIU;Yaru WEN;Xianghui ZHOU;Yanlin ZHANG;Xiongwei LI;Deng WANG;Fan LUO;Cheng CHEN

作者机构：Hubei Geological SurveyWuhanHubei 430034China Key Laboratory of Continental shale Accumulation and Development of Ministry of EducationNortheast Petroleum UniversityDaqing 163318China Coal Reservoir Laboratory of National Engineering Research Center of CBM Development&UtilizationSchool of Energy ResourcesChina University of GeosciencesBeijing 100083China The Seventh Geological Brigade of Hubei Geological BureauYichang 443000China 

出 版 物：《Frontiers of Earth Science》 (地球科学前沿（英文版）)

年 卷 期：2021年第15卷第2期

页      面：310-331页

核心收录：

学科分类：081803[工学-地质工程] 08[工学] 0818[工学-地质资源与地质工程] 

基　　金：supported by the Scientific Research project of Department of Natural Resources of Hubei Province(No.ZRZY2020KJ10) Hubei Geological Bureau(No.KJ2019-3) the Shale Gas Geological Survey Projects of Department of Natural Resources of Hubei Province(Nos.HBCZ-17060223-170397 and DTCG-190409) We also thank the funds provided by Youth Foundation of the Northeast Petroleum University(No.2019QNL-21) Opening Fund of the Coal Reservoir Laboratory of National Engineering Research Center of CBM Development&Utilization,China University of Geosciences(Beijing)(No.2019MCQ02001) 

主　　题：shale gas Niutitang Formation accumulation conditions factors influencing the gas content sedimentary facies 

摘      要：The lower Cambrian Niutitang Formation is of crucial importance for shale gas target reservoirs in western Hubei,China;however,little work has been done in this field,and its shale gas accumulation and enrichment mechanism are still *** on survey wells,outcrop data,and large numbers of tests,the geological conditions of shale gas accumulation were studied;moreover,the factors that influence the gas content were thoroughly *** results show that the Niutitang Formation(Є1n)can be divided into three sections:the first section(Є_(1)n^(1)),the second section(Є_(1)n^(2)),and the third section(Є1n3).TheЄ_(1)n^(2) is the main shale gas *** deep shelf facies is the main sedimentary facies and can be divided into three main lithofacies:argillaceous siltstone,carbonaceous shale and carbonaceous siliceous *** total organic carbon(TOC)content shows gentle growth trends until bottom of theЄ_(1)n^(2) and then decreases rapidly within theЄ_(1)n^(1),and the TOC content mainly ranges from 2%to 4%*** calcite and dolomite dissolution pores,clay intergranular pores and organic pores are the main pore types and the micropore types are clearly related to the mineral compositions and the TOC ***,the gas content is mainly affected by the TOC ***,wells with high gas contents are distributed only southeast of the Huangling anticline,and the combination of structural styles,fault and fracture development,and the distribution of the regional unconformity boundary between the upper Sinian Dengying Formation(Z2d)and theЄ_(1)n^(2) are the three most important factors affecting the gas *** favorable areas must meet the following conditions:a deep shelf environment,the presence of theЄ_(1)n^(1),wide and gentle folds,far from large normal faults that are more than 5 km,moderate thermal evolution,and greater than 500 m burial depth;this includes the block with the YD2–ZD2 wells,and the block with the Y1 and YD4 wel