川西北部地区飞仙关组层序地层格架及镶边台地沉积演化

Sequence stratigraphic framework and rimmed platform sedimentary evolution of Feixianguan Formation in Northwestern Sichuan Basin

完颜泽 王明磊 郑超 王旭丽 尹宏 罗洋 王宇峰 胡欣 李润彤 汤潇

中国石油勘探开发研究院，北京 100083 中国石油西南油气田公司勘探开发研究院，四川 成都 610500 中国石油西南油气田公司川西北气矿，四川 江油 621709 中国石油西南油气田公司技术咨询中心，四川 成都 610500

Exploration and Development Research Institute, PetroChina, Beijing 100083, China Exploration and Development Research Institute, Southwest Oil and Gas Field Company, PetroChina, Chengdu 610500, China Northwest Sichuan Gas District, Southwest Oil and Gas Field Company, PetroChina, Jiangyou 621709, China Technical Consulting Center, Southwest Oil and Gas Field Company, PetroChina, Chengdu 610500, China

川西北部地区飞仙关组多口井测试获气流，由于储层物性差异，使得测试产量差别较大。为进一步明确飞仙关组滩相储层发育及演化规律，文中利用层序地层学理论及岩心、测录井、地震资料，对飞仙关组地层层序进行逐级划分，并在层序地层格架的基础上，开展沉积模式与优质储层发育规律分析。研究表明：飞仙关组划分为3个三级层序、6个体系域，发育开阔台地—台地边缘—台前斜坡—海槽（盆）沉积体系，台地向北东方向逐渐迁移，并在SQ1沉积期晚期将开江—梁平海槽填平补齐；SQ2沉积期台地边缘迁移至九龙山地区，广泛发育台内鲕粒滩与台缘鲕粒滩微相；SQ3沉积期整体为浅水、平缓的局限￣蒸发沉积；具有白云岩化、强溶蚀作用的滩体发育区是飞仙关组优质储层发育区，即SQ2台缘滩发育区。

Many wells of Feixianguan Formation in Northwestern Sichuan Basin have been tested and obtained gases, but the test production varies greatly due to the difference of reservoir physical properties. In order to further clarify the development and evolution law of beach facies reservoir in Feixianguan Formation, the stratigraphic sequence of Feixianguan Formation is divided step by step by using the theory of sequence stratigraphy, core, logging and seismic data, and the sedimentary model and development law of high-quality reservoir are analyzed on the basis of sequence stratigraphic framework. The results show that Feixianguan Formation can be divided into three third-order sequences and six system tracts, which developed open platform, platform margin, platform foreslope and trough (marine basin) sedimentary system. The platform gradually migrated northeastward, and the Kaijiang-Liangping trough was filled up in the late SQ1 sedimentary period. The platform margin migrated to Jiulongshan area in the SQ2 sedimentary period, and the oolitic shoal microfacies in the platform and platform margin were widely developed. The shallow water and  gentle restricted-evaporite deposition were developed in SQ3 period. The beach development area with dolomitization and strong dissolution is the high-quality reservoir development area of Feixianguan Formation, namely SQ2 platform margin beach development area.

10.6056/dkyqt202205010