郭局子洼陷湖缘峡谷及其对洼陷储集砂体的贡献

Brink canyons and its contribution to reservoir sand,Guojuzi Sag

对车镇凹陷郭局子洼陷沙河街组进行了精细的三维地震解释,从盆地的构造形态入手,识别出存在于盆地内的2个主要湖缘峡谷,并详细分析了这2条峡谷的形态和沉积充填特征。结合前人对湖缘峡谷发育模式的研究成果,从成因角度确定了在峡谷的影响下洼陷内部形成了辫状河三角洲和湖底扇沉积。在此基础上,进一步研究了湖缘峡谷沉积体系对洼陷内部储集砂体的贡献以及对油气成藏的影响。湖缘峡谷沉积体系对郭局子洼陷的储层具有重要影响,可以形成有利的储盖组合和油气运移通道,具备良好的成藏条件。

Base on the delicate 3D seismic interpretation in Shahejie Formation for Guojuzi Sag of Chenzhen Depression,two main brink canyons were found according to the structural attitude of the basin.The structural attitude and depositional characteristics of these two canyons were analyzed in detail.The braid delta and sublacustrine fan deposits influenced by canyon were recognized inside the sag from the point of genesis based on the research results of the development pattern of brink canyons.Then the effects of brink canyon depositional system on reservoir sandbod-ies and oil-gas accumulation inside the sag were researched.The brink canyon sedimentary system has important influence on the reservoirs in Guojuzi Sag which may result in favorable reservoir-seal combination,oil-gas migration pathway and hydrocarbon accumulation condition.