川西中段上沙溪庙组层序格架下成岩相及储层评价

Diagenetic facies and reservoir evaluation in sequence framework of Upper Shaximiao Formation in middle area of western Sichuan Depression

陈贤良 纪友亮 杨克明

西安科技大学地质与环境学院，陕西 西安 710054 中国石油大学（北京）油气资源与探测国家重点实验室，北京 102249 中国石化西南油气分公司勘探开发研究院，四川 成都 610016

College of Geology and Environment, Xi′an University of Science and Technology, Xi′an 710054, China State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China Research Institute of Exploration and Development, Southwest Oil ＆ Gas Company, SINOPEC, Chengdu 610016, China)

基于铸体薄片、阴极发光、电子探针、扫描电镜等实验方法，针对川西中段上沙溪庙组砂岩储层中压实、胶结、溶蚀3种主控成岩作用，开展层序格架下定量成岩相研究及储层综合评价。研究结果表明：1）上沙溪庙组为一个三级层序，内部可划分出低位、湖侵和高位体系域；2）依据压实、胶结、溶蚀定量成岩强度标准和计算结果，划分出5种主要成岩相类型；3）层序格架下成岩相展布受沉积相控制明显，湖侵体系域不发育强胶结中溶蚀成岩相，成岩相平面展布与低位、高位体系域差异较大；4）依据储集潜力大小将储层划分为4类，其中Ⅱ类储层为研究区较好的储层。

Aiming at the major diagenesis of compaction, cementation and dissolution, the quantitative diagenetic facies and comprehensive reservoir evaluation in sequence framework of the Upper Shaximiao Formation in the middle area of the western Sichuan Depression were carried out by means of casting thin sections, cathodoluminescence, electron probe and scanning electron microscopy. The results show: (1) The upper Shaximiao Formation is a three?鄄order sequence, and it can be divided into lowstand systems tract, transgressive system tract and highstand systems tract. (2) According to the standard of diagenesis and calculation of compaction, cementation and dissolution, the five major diagenetic facies types were classified. (3) Distribution of diagenetic facies within the sequence stratigraphic frame was significantly controlled by sedimentary facies. The distribution of diagenetic facies in transgressive system tract is quite different from the lowstand and highstand system tract and it did not develop strong cementation with medium dissolution facics. (4) The reservoir was divided into four types according to the reservoir potentials, and type Ⅱ is the favorable reservoir type in the study area.

10.6056/dkyqt201905002