川西雷口坡组气藏储层类型及孔隙结构特征

Reservoir types and pore structure characteristics of Leikoupo Formation carbonate reservoir in western Sichuan

陈昱林 曾焱 吴亚军 段永明 张岩2

中国石化西南油气分公司博士后科研工作站，四川 成都 610041 中国石化西南油气分公司勘探开发研究院，四川 成都 610041

Post-Doctoral Scientific Research Station, Southwest Oil & Gas Company, SINOPEC, Chengdu 610041, China Research Institute of Exploration and Development, Southwest Oil and Gas Company, SINOPEC, Chengdu 610041, China

川西海相碳酸盐岩雷口坡组气藏的储层岩性主要为白云岩，储层薄且呈互层状发育，主要储集空间为溶蚀孔洞，微裂缝发育，非均质性极强，储层类型复杂，气藏高效开发难度较大，对储层类型和孔隙结构特征的研究可以为气藏效益开发提供重要支撑。因此，以研究区3口探井的岩心样品为研究对象，综合运用岩心观察、铸体薄片、物性测试、压汞实验和CT扫描等方法对储层类型进行划分，并对不同类型储层的孔隙结构特征进行了分析。结果显示川西雷口坡组气藏主要发育孔隙型、裂缝￣孔隙型、孔洞型和裂缝￣孔洞型4类储层，同时发现排驱压力、分选系数、连通孔隙数量占比、配位数和孔隙纵横比与储层类型和物性参数有一定的对应性。

The reservoir lithology of marine carbonate rocks of Leikoupo Formation gas reservoir in western Sichuan is mainly dolomite, which is thin and layered. The main reservoir space is of dissolution pore, and the micro-fractures are also developed. The highly heterogeneous and complex reservoir types cause much difficulty in the efficient development of these gas reservoirs. The study of reservoir types and pore structure can provide important support for the benefit development of these gas reservoirs. Therefore, the core samples of three exploration wells in the study area were used to study the reservoir types, integrating core observation, casting flakes, physical property test, mercury intrusion test and CT scanning to classify reservoir types and analyze the pore structure characteristic. The results show that four types of gas reservoirs are developed in the Leikoupo Formation, western Sichuan: pore type, fracture-pore type, pore-vuggy type and fracture-pore-vugg type. The displacement pressure, the sorting coefficient, the number of connected pores and the aspect ratio of the pore are related to the reservoir type and physical parameters.

10.6056/dkyqt201803003