川北地区中二叠统茅二段储层特征及控制因素分析

Reservoir characteristics and its controlling factor of the second Member of the Middle Permian Maokou Formation in northern Sichuan region

刘宣威 田亚铭 张慧 李翔 罗启超 黄正

中国石油大学（北京）地球科学学院，北京 102249 成都理工大学自然资源部构造成矿成藏重点实验室，四川 成都 610059 中国石油天然气股份有限公司储气库分公司，北京 102206 中国石化华东石油工程有限公司江苏钻井公司，江苏 扬州 224261

School of Earth Sciences, China University of Petroleum, Beijing 102249, China Key Laboratory of Tectonic Controls on Mineralization and Hydrocarbon Accumulation of Ministry of Natural Resource, Chengdu University of Technology, Chengdu 610059, China Gas Storage Company, PetroChina, Beijing 102206, China Jiangsu Drilling Company, East China Petroleum Engineering Co., Ltd., SINOPEC, Yangzhou 224261, China

为明确川北地区中二叠统茅二段碳酸盐岩储层发育机制及控制因素，文中选取典型井及剖面，利用薄片鉴定、阴极发光、扫描电镜、物性分析、高压压汞等手段，对茅二段储层特征及控制因素进行了分析。结果表明：1）茅二段为碳酸盐岩台地沉积，孔渗条件较差，依赖裂缝及成岩作用改造；2）茅口组储层成岩作用复杂，发生多期次溶蚀及白云岩化作用；3）储层受构造活动、沉积及成岩作用等多种因素共同控制。构造演化及古地貌影响了沉积及成岩作用范围，茅口组发育的滩体是储层形成的物质基础，后期岩溶改造叠加白云岩化是储层形成的关键。

In order to clarify the development mechanism and controlling factors of the second Member carbonate reservoir of the Middle Permian Maokou Formation in northern Sichuan region, the reservoir characteristics and controlling factor of second Member of the Maokou Formation were studied by the means of drilling and profile data, sheet identification, cathodoluminescence, scanning electron microscopy, physical property analysis, and high-pressure mercury injection. The results show that: (1) the second Member of the Maokou Formation is carbonate platform deposition with worse porosity and permeability conditions, which rely on the transformation of fracture and diagenesis; (2) the reservoir of Maokou Formation has complex diagenetic action and is subject to multi-stage dissolution and dolomitisation; (3) the reservoir is controlled by multiple factors such as structure activity, sedimentation and diagenesis. The tectonic evolution and paleogeomorphology affect the sedimentary and diagenetic range, the mudflats developed in the Maokou Formation are the material basis for reservoir formation, and the late karst transformation superimposed dolomitization is the key to reservoir formation.

10.6056/dkyqt202204005