潜江凹陷潜江组T-R旋回层序与非构造圈闭预测

Transgression regression cyclic sequences and nonstructural traps prediction in Qianjiang Formation,Qianjiang Depression

潜江凹陷为一陆相断陷湖盆。运用T-R旋回的基本概念与原理,结合潜江凹陷测井、地震及岩心资料,将潜江组划分为8个三级T-R旋回层序,同时建立了该凹陷T-R旋回层序地层学模式。在此基础上,识别出扇三角洲、湖底扇和深湖—半深湖等沉积体系。查明了该区主要层段的砂体分布规律,确立有利于非构造圈闭发育的砂体类型,并提出了有利的勘探方向。

Qianjiang Depression is a continental fault lacustrine basin. By using basic T-R (Transgression Regression) cyclic concepts and principles eight third-grade T-R sedimentary cycles were classi-fled in the Qianjiang Formation according to comprehensive research of log data,seismic data and core samples. And the sequence stratrigraphic framework pattern of T-R cycles in the depression was established. Sedimentary systems were identified including fan delta,sublacustrine fan and deep lake-semi deep lake facies. The sandbodies distribution in major target intervals and favorable sandbody types for nonstructural traps development were recognized, as well as the favorable exploration direction was proposed.