东濮凹陷古近纪断裂活动对沉积的控制作用

为了研究东濮凹陷的盆地结构、断裂活动及其对沉积的控制作用，开展了地震资料解释、非地震物探资料分析、钻井岩心和测井曲线分析。结果表明：①东濮凹陷古近纪盆地具有多断、多凸、多洼的结构特征。始新统沙河街组沙四段沉积期为单断湖盆，湖平面宽广，形成了一套优质烃源岩，为三角洲、浅湖—半深湖沉积，局部见深湖沉积。②沙三段下亚段沉积期以“多凸—多洼”构造样式为主，湖盆中心向西迁移，生烃层段较沙四段有所变化，为三角洲、浅湖、半深湖和深湖沉积。③沙二段上亚段沉积期继承性发育多洼构造，湖盆萎缩，生烃潜力变差，卫东—文东断层系开始发育，导致东部的洼陷区沉降幅度加大，烃源岩快速成熟。④断层活动频繁期，断距大的区域发育优质烃源岩，邻近烃源岩的近洼带发育的三角洲前缘砂体、滩坝砂和浊积砂均是良好的储集层；早期形成且长期活动的二、三级断层是油气运移的主要通道。因此，可以判断柳屯洼陷和濮卫洼陷的浊积砂岩油气藏与马寨洼陷沙三段的上倾尖灭型油藏均为未来勘探挖潜方向。该研究成果对东濮凹陷的勘探具有指导意义。

Control of fault activity on sedimentation of Paleogene in Dongpu Sag

In order to study the basin structure,fault activity and its control on sedimentation in Dongpu Sag, seismic data interpretation,non-seismic geophysical data analysis,drilling core and logging curve analysis were carried out. The results show that:(1)The Paleogene basin in Dongpu Sag had the structural characteristics of multi-fault,multi-convex and multi-subsag. The fourth member of Shahejie Formation of Eocene was a single fault lake basin with broad lake surface,forming a set of high-quality source rocks,which were mainly composed of deltaic facies and shallow and semi-deep lake subfacies,and locally deep lake subfacies.(2)The lower submember of the third member of Shahejie Formation was dominated by the structural style of"multi-convex and multi-subsag". The center of the lake basin moved westward,and the hydrocarbon generation interval was somewhat different from that of Sha-4 member. The deposits were delta,shallow lake,semi-deep and deep lake. (3)During the sedimentary period of the upper sub-member of the second member of Shahejie Formation,multisubsag developed successively,the lake basin shrank,and the hydrocarbon generation potential became worse. The Weidong-Wendong fault system began to develop,resulting in a larger sedimentation range in the subsag area in the east and rapid maturity of hydrocarbon source rocks.(4)During the period of frequent fault activity,highquality hydrocarbon source rocks were developed in the region with large fault spacing,and delta front sand bodies, beach bar sand and turbidite sand developed in the nearby subsags adjacent to hydrocarbon source rocks were all good reservoirs. The early formed and long-term active secondary and tertiary faults were the main channels for hydrocarbon migration. Therefore,the turbidite sandstone reservoirs in Liutun and Puwei subsags,the updip pinch-out reservoirs of Sha-3 member in Mazhai subsag can be judged as the tapping potential of future exploration. The research results have guiding significance for the exploration of Dongpu Sag.