Microscopic oil occurrence in high-maturity lacustrine shales:Qingshankou Formation,Gulong Sag,Songliao Basin

作     者：Jing-Ya Zhang Ru-Kai Zhu Song-Tao Wu Xiao-Hua Jiang Chang Liu Yi Cai Su-Rong Zhang Tian-Shu Zhang 

作者机构：Research Institute of Petroleum Exploration and DevelopmentPetroChinaBeijing100083China 

出 版 物：《Petroleum Science》 (石油科学（英文版）)

年 卷 期：2023年第20卷第5期

页      面：2726-2746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：funded by the National Natural Science Foundation of China(Project 42090025 and 42202152) Heilongjiang Province open competition projects:“Research on the shale oil phase state,seepage mechanism,and integrated geologicalengineering stimulation technology in the Gulong Sag”and“Research on the diagenetic dynamic evolution process and its coupling relationship with pores and fractures” 

主　　题：Shale oil content Occurrence states Micro-oil distribution Effective pore spaces Controlling factors Gulong sag 

摘      要：Occurrence and mobility of shale oil are prerequisites for evaluating shale oil reserves and prioritizing exploration targets,particularly for heterogeneous lacustrine *** Qingshankou Formation in the Gulong Sag,Songliao Basin is a classic lacustrine pure shale reservoir that contains abundant shale oil *** predicted geological reserves of the shale are 1.268×10^(9) *** this study,field emission scanning electron microscope(FE-SEM),the modular automated processing system(MAPS),pyrolysisgas chromatography(Py-GC),low-pressure nitrogen gas adsorption(LPNA),Soxhlet extraction,pyrolysis,and 2-D nuclear magnetic resonance(NMR)were integrated to describe the shale oil components,microscopic occurrence,mobility,and the effective pore size ***,the related controlling factors are *** shale oil in the Qingshankou Fm exists dominantly in the matrix pores of the clay minerals,with small amounts distributed in the intergranular pores of terrigenous clastic grains,intercrystalline pores of pyrite,intragranular pores of ostracod shells,and *** oil is distributed in the pore spaces of variable sizes in different *** clay mineral-laminated shales are characterized by the broadest range of pore size and largest volume of pore spaces with shale oil distribution,while the ostracod-laminated shales have limited pore spaces retaining ***,the proposed integrated analysis evaluates the shale oil molecules existing in two states:movable,and adsorbed oil,*** result illustrates that movable oil takes up 30.6%e79.4%of the total residual ***,mineral composition,and pore structures of the shale joint together to control the states and mobility of the shale *** values are positively correlated with the quantities of shale oil regardless of the state of *** mineral components significantly impact the state of shale *** differences in the states of oil were observed following