Morphological classification and three-dimensional pore structure reconstruction of shale oil reservoirs: A case from the second member of Paleogene Kongdian Formation in the Cangdong Sag, Bohai Bay Basin, East China

作     者：FAN Yuchen LIU Keyu PU Xiugang ZHAO Jianhua FAN Yuchen;LIU Keyu;PU Xiugang;ZHAO Jianhua

作者机构：China University of Petroleum(East China)Qingdao 266580China Laboratory for Marine Mineral ResourcesQingdao National Laboratory for Marine Science and TechnologyQingdao 266071China PetroChina Dagang Oilfield CompanyTianjin 300280China 

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5期

页      面：1085-1097页

核心收录：

学科分类：0820[工学-石油与天然气工程] 08[工学] 0708[理学-地球物理学] 082002[工学-油气田开发工程] 

基　　金：Science Fund of China National Natural Science Foundation for Creative Research Groups(41821002) the 14(th)Five-Year Plan Major Project of Pilot National Laboratory for Marine Science and Technology(2021QNLM020001) the Dagang Oil Field Company Project(DQYT-2019-JS-365) 

主　　题：shale oil pore structure LV-FIB-SEM 3D reconstruction Paleogene Kongdian Formation Cangdong Sag Bohai Bay Basin 

摘      要：This study combines large volume three-dimensional reconstruction via focused ion beam scanning electron microscopy(FIB-SEM) with conventional scanning electron microscope(SEM) observation, automatic mineral identification and characterization system(AMICS) and large-area splicing of SEM images to characterize and classify the microscopic storage space distribution patterns and 3D pore structures of shales in the second member of the Paleogene Kongdian Formation(Kong 2) in the Cangdong Sag of the Bohai Bay Basin. It is shown that:(1) The Kong 2 Member can be divided into seven types according to the distribution patterns of reservoir spaces: felsic shale with intergranular micron pores, felsic shale with intergranular fissures, felsic shale with intergranular pores, hybrid shale with intergranular pores and fissures, hybrid shale with intergranular pores, clay-bearing dolomitic shale with intergranular pores, and clay-free dolomitic shale with intergranular pores.(2) The reservoir of the intergranular fracture type has better storage capacity than that of intergranular pore type. For reservoirs with storage space of intergranular pore type, the dolomitic shale reservoir has the best storage capacity, the hybrid shale comes second, followed by the felsic shale.(3) The felsic shale with intergranular fissures has the best storage capacity and percolation structure, making it the first target in shale oil exploration.(4) The large volume FIB-SEM 3D reconstruction method is able to characterize a large shale volume while maintaining relatively high spatial resolution, and has been demonstrated an effective method in characterizing the 3D storage space in strongly heterogeneous continental shales.