渤海中部海域大型湖底扇地球物理响应及勘探意义

Geophysical response of large sublacustrine fan in central Bohai Sea and its exploration significance

针对渤海中部海域大型湖底扇边界识别及富砂性预测难度大的问题,基于砂质碎屑流湖底扇沉积模式,综合利用古近系东营组第二段下亚段钻井岩性、测井、薄片、地震数据等资料,对湖底扇沉积特征、地震响应特征进行系统分析和描述。在此基础上,利用地层切片、多属性预测及正演模拟等技术对湖底扇内幕进行刻画,落实内部多期扇体的空间分布特征,预测有利砂体发育部位。该湖底扇毗邻烃源岩,岩性圈闭面积大,盖层广泛发育,油气运移聚集条件优越,是岩性油气藏勘探的重要靶区。

Based on the data of depositional model of sandy debris flow sublacustrine fan,comprehensive utilization of drilling lithology and logging as well as thin section identification from the second member of Paleogene Dongying Formation,the seismic responses of the sublacustrine fan sedimentary characteristics are analyzed and described in order to resolve the boundary identification of sublacustrine fan sand-rich prediction in central Bohai Sea.Stratigraphic slicing,multi-attribute prediction and forward modeling techniques are used to characterize the interior of the sublacustrine fan,to confirm the spatial distribution characteristics of the internal multi-phase fan,and to predict the development locations of favorable sand bodies.It is realized that the sublacustrine fan is adjacent to the source rock,has a large area of lithologic traps,widely developed caprocks and favorable conditions for hydrocarbon migration and accumulation,so it is an important target area for lithologic reservoir exploration.