靖吴地区延长组长6沉积特征研究

Study on Sedimentary Characteristics of Chang 6 of Yanchang Formation in Jingwu Area

为了研究靖吴地区长6储层沉积特征,通过岩心观察、薄片鉴定、沉积构造和测井曲线响应等综合分析,本文对研究区沉积相标志、沉积相类型、微相展布及微相演化规律进行研究。结果显示,靖吴地区长6储层沉积体系为河控三角洲沉积体系,且三角洲前缘亚相、前三角洲-浅湖沉积占主导地位。沉积微相有水下分流河道、水下天然堤、分流间湾、水下决口扇、河口坝、远砂坝六种,三角洲前缘的水下分流河道是储层砂岩发育的骨架,且水下分流河道砂体是储层最有利储层发育的相带,其次为三角洲前缘河口坝砂体。

In order to study the sedimentary characteristics of Chang-6 reservoir in Jingwu area,through comprehen⁃sive analysis of core observation,thin section identification,sedimentary structure and logging curve response,this paper studied the sedimentary facies signs,sedimentary facies types,microfacies distribution,and microfacies evolu⁃tion laws in the study area.The results show that the Chang 6 reservoir sedimentary system in the Jingwu area is a riv⁃er-controlled delta sedimentary system,and the delta front subfacies and pre-delta-shallow lake sediments domi⁃nate.There are six types of sedimentary microfacies,namely underwater distributary channel,underwater natural dike,distributary bay,underwater rupture fan,estuary dam,and remote sand dam.The underwater distributary chan⁃nel of the delta front is the framework of the reservoir sandstone development,and the underwater distributary chan⁃nel sand body is the most favorable facies belt for the reservoir development,followed by the delta front estuary bar sand body.