泌阳凹陷基岩油气成藏条件分析

泌阳凹陷是一新生代富含油气的小型山间断陷盆地,凹陷的形成主要受北西向的唐河-栗园断裂和北东向的栗园-泌阳断裂控制,构成一个东南深、西北浅的扇形箕状断陷。在凹陷东南边界断裂陡坡带上,具有较好生烃条件的巨厚古近系核桃园组与古老变质岩系侧向接触,易形成基岩油藏,通过对凹陷的层序地层发育、沉积体系、边界断裂样式、烃源岩成烃条件、凹陷南缘油气苗调查以及基底岩性和其储集条件等方面的分析,研究了东南边界断裂陡坡带上基岩油藏的有利成藏条件,建立了基岩油藏的成藏模式,指出了有利勘探目标。

A study on Petroleum Accumulation in Basement Reservoir, Biyang Sag

Biyang sag is a small half-graben basin full of oil and gas of Cenozoic.With its formation controlled by Tanghe-Liyuan fault of N-W strike and Liyuan-Biyang fault of N-E strike,Biyang sag is a fan-shaped and halfgraben-like basin which is deep in southeastern part and shallow in northwestern part.It is found that a huge thickness of Hetaoyuan formation of Paleogene with good hydrocarbon-generating conditions is laterally contacted to the old metamorphic complex on the faulting arctic region in the southeastern margin of Biyang sag,which allows to forming basement reservoirs.This paper presents the sag's sequence stratigraphy,sedimentary system,marginal faulting style,source rock condition and oil shows investigation in the southern margin as well as basement lithology and reservoir quality.The petroleum accumulation models of basement reservoir on this arctic region are then development.The advantageous targets for petroleum exploration are given.