Lithofacies and pore features of marine-continental transitional shale and gas enrichment conditions of favorable lithofacies:A case study of Permian Longtan Formation in the Lintanchang area,southeast of Sichuan Basin,SW China

作     者：WANG Enze GUO Tonglou LIU Bo LI Maowen XIONG Liang DONG Xiaoxia ZHANG Nanxi WANG Tong WANG Enze;GUO Tonglou;LIU Bo;LI Maowen;XIONG Liang;DONG Xiaoxia;ZHANG Nanxi;WANG Tong

作者机构：School of Earth and Space SciencesPeking UniversityBeijing 100871China Southwest Oil&Gas CompanySinopecChengdu 610041China Petroleum Exploration and Production Research InstituteSinopecBeijing 100083China Research Institute of Exploration and DevelopmentSinopec Southwest Oil and Gas CompanyChengdu 610041China 

出 版 物：《Petroleum Exploration and Development》 (石油勘探与开发（英文版）)

年 卷 期：2022年第49卷第6期

页      面：1310-1322页

核心收录：

学科分类：0820[工学-石油与天然气工程] 081803[工学-地质工程] 08[工学] 0818[工学-地质资源与地质工程] 0708[理学-地球物理学] 082002[工学-油气田开发工程] 

基　　金：Supported by the National Natural Science Foundation (U19B6003). 

主　　题：marine-continental transitional shale pore type shale lithofacies formation mechanisms Permian Longtan Formation shale gas Sichuan Basin 

摘      要：In this work,the Permian Longtan marine-continental transitional shale in the southeast of Sichuan Basin was taken as study object.Through petrology and geochemical analysis,lithofacies types of the marine-continental transitional shale were classified,key controlling factors of physical properties and gas content of the different shale lithofacies were analyzed.The research results show that the Longtan Formation marine-continental transitional shale in the study area has four types of lithofacies,namely,organic-lean calcareous shale,organic-lean mixed shale,organic-lean argillaceous shale,and organic-rich argillaceous shale,among which the organic-rich argillaceous shale is the most favorable lithofacies of the study area.The pore types of different lithofacies vary significantly and the clay mineral-related pore is the dominant type of the pore system in the study area.The main controlling factor of the physical properties is clay mineral content,and the most important factor affecting gas content is TOC content.Compared with marine shale,the marine-continental transitional shale has low average values,wide distribution range,and strong heterogeneity in TOC content,porosity,and pore structure parameters,but still contains some favorable layers with high physical properties and gas contents.The organic-rich clay shale deposited in tidal flat-lagoon system is most likely to form shale gas sweet spots,so it should be paid more attention in shale gas exploration.