Multi-scale fractures formation and distribution in tight sandstones—a case study of Triassic Chang 8 Member in the southwestern Ordos Basin
作者机构:Key Laboratory of Tectonics and Petroleum ResourcesChina University of GeosciencesWuhan 430074China Wenhua CollegeWuhan 430074China Faculty of Petroleum and Natural ResourcesSana’a UniversitySana’aYemen Louisiana State UniversityBaton Rouge LA 7080USA
出 版 物:《Frontiers of Earth Science》 (地球科学前沿(英文版))
年 卷 期:2022年第16卷第2期
页 面:483-498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:We thank the financial support from the National Natural Science Foundation of China(Nos.41902147 and 41402117) the China National Science and Technology Major Project(No.2016ZX05048-001-01-CS).We also thank the Sinopec Huabei Company for providing the core samples and the other data sets,and the permission to publish this article
主 题:natural fractures characteristics geological significance tight sandstone reservoir Upper Triassic Yanchang Formation
摘 要:Fracture system is an important factor controlling tight oil accumulation in the Triassic Chang 8 Member,southwestern Ordos Basin,China.A systematic characterization of the multi-scale natural fractures is a basis for the efficient tight oil *** on outcrops,seismic reflections,well cores,well logs(image and conventional logging),casting thin sections,and scanning electron microscope observation,the multi-scale fractures occurrences and their influences on Chang 8 tight sandstone reservoirs are *** results show that three periods of strike-slip faults and four scales of natural fractures developed,namely mega-scale(length7×10^(7) mm),macro-scale(3.5×10^(5)length7×10^(7) mm),meso-scale(10length3.5×10^(5) mm),and micro-scale(length10 mm)*** mega-and macro-scale fractures developed by strike-slip faults are characterized by strike-segmentation and lateral zonation,which connect the source and *** scale fractures also influence the distribution and effectiveness of traps and reservoirs,which directly influence the hydrocarbon charging and *** meso fractures include the tectonic,diagenetic,as well as hydrocarbon generation-related overpressure *** meso-and micro-scale fractures improve the sandstone physical properties and also the tight oil well production *** integrated study helps to understand the distribution of multi-scale fractures in tight sandstones and provides a referable case and workflow for multi-scale fracture evaluation.