辽中凹陷中深层储层质量评价及隐蔽砂体成藏条件分析

Reservoir quality evaluations for the middle-deep intervals and reservoiring condition analyses for the subtle sandbodies in Liaozhong depression

从成岩作用分析入手,探讨了辽中凹陷中深层储层质量问题,并运用古地貌和坡折带共同控制隐蔽砂体展布的理论,对该凹陷深洼区低位隐蔽砂体的发育背景和成藏条件进行了分析,认为辽中凹陷中深层次生孔隙发育带是潜在的有利储层,其孔渗性能较好;该凹陷深洼区发育低位隐蔽砂体,这些隐蔽砂体具有良好的成藏条件,易于形成自生自储或下生上储的隐蔽油气藏;深洼超压区发育的低位隐蔽砂体是该凹陷中深层隐蔽油气藏勘探的重点目标。

In Liaozhong depression, the reservoir quality is evaluated for the middle-deep intervals by starting at diagenesis analyses,and the develop- ment settings and reservoiring conditions of subtle sandbodies are analyzed for a deep-sagged area by using a concept that palaeogeomorphology and slope breaks would commonly control distribution of subtle sandbodies, resulting in several conclusions： （1） The middle-deep zones of secondary porosity are favorable potential reservoirs with higher porosity and permeability; （2）Several low-stand subtle sandbodies were developed in the deepsagged area, which are favorable to form subtle hydrocarbon reservoirs of self generation-self reservoiring or lower generation-upper reservoiring due to their excellent reservoiring conditions; （3）The overpressured subtle sandbodies in the deep-sagged area may be important targets for the middle-deep intervals＇ exploration in this depression.