伊宁凹陷二叠系油气系统与勘探目标

Permian petroleum system and exploration targets in Yining depression, Xinjiang, China

伊犁盆地是西天山褶皱带中一个构造残留盆地,纵向上发育二叠系、侏罗系两套烃源层系,形成上、下两套油气系统。伊宁凹陷是伊犁盆地中最大的一个二级构造单元。其中二叠系油气系统经历了侏罗纪末期及第三纪以来的两次成烃充注,分别与晚海西及燕山期所形成的构造圈闭相匹配,是伊宁凹陷有效的、主要的油气系统。南部斜坡带是有利的油气勘探区带,断块、断鼻及岩性地层不整合油气藏是主要的勘探目标。

Yili basin is a residual basin developed in the western Tianshan Mountains folded belt. It was developed on the early Paleozoic broken basement and went through several stages of tectonic movements. There are two sets of source rocks developed in the basin and two petroleum systems can be classified. The Yining depression is the largest secondary tectonic unit. The petroleum was filled to the Permian System in the end of Jurassic and since Tertiary, which matched the traps formed in late Hercynian and Yanshan Period. It is considered to be an effective and primary petroleum system. The south slope is the advantageous belt for exploration. The main exploration targets are faulted blocks, faulted nose-shaped traps and litho-stratigraphic-unconformity traps.