Enrichment and exploration of deep lacustrine shale oil in the first member of Cretaceous Qingshankou Formation, southern Songliao Basin, NE China

作者：Junfeng Zhang, Xingyou Xu, Jing Bai, Weibin Liu, Shan Chen, Chang Liu, Yaohua Li · 发表于：Petroleum Exploration and Development · 年份：2020 · DOI：10.1016/s1876-3804(20)60085-4 · 被引用次数：54 · 研究领域：Hydrocarbon exploration and reservoir analysis、Atmospheric and Environmental Gas Dynamics、Hydraulic Fracturing and Reservoir Analysis

Pure shales in the first member of Qingshankou Formation (simplified as Qing 1 Member) in the southern Songliao Basin, i.e., the semi-deep and deep lacustrine shales, are characterized by a high content of clay minerals and poor hydrocarbon mobility, making the development of shale oil difficult. According to the drilling and testing results, the shale of Qing 1 Member can be classified into 3 lithofacies, i.e., bedded argillaceous shale, laminated diamictite shale, and interbedded felsic shale. The TOC and brittle minerals control the enrichment of shale oil, of them, TOC controls the total oil content, in other words, the total oil content increases with the increase of TOC; while the laminae made up of brittle minerals contain a large number of bigger intergranular pores which are favorable enrichment space for movable shale oil. In consideration of the origins of the 3 lithofacies, two shale oil enrichment models are classified, i.e., the deep lacustrine high-TOC bedded argillaceous shale (Model-I) and the semi-deep lacustrine moderate-high-TOC laminated diamictite shale (Model-II). In the Model-I, the shale is characterized by high hydrocarbon generation ability, high total oil content, abundant horizontal bedding fractures, and vertical and high angle fractures locally; the complex fracture network formed by horizontal bedding fractures and vertical fractures improve the storage capacity and permeability of the shale reservoir, increase the enrichment space for movable ...