Based on seismic,logging,formation testing,core and lab test data,this study analyzed the sequence division,facies features of deep water deposits and modes,development of large-scale gravity flow,reservoir physical properties and their main controlling factors,and proposed a classification standard and prediction method of favorable exploration areas in deep water area of the Binl oil layers of the lower sub-member of the first member of Paleogene Shahejie Formation in Banqiao-Qibei slope zone of Qikou sag,Bohai Bay Basin.The Binl oil layers can be divided into three fifth-order sequences,each less than 100 m thick;a set of gravity flow deposits were formed under deep water background in the slope zone,which contains sedimentary micro-facies such as main channel,distributary channel,channel margin,inter-channel mudstone,and turbidite sand sheet in areas without channels,and,in space,has inherited and constructive development features of multistages.It is a sedimentary sequence of fan delta-distal subaqueous fan-deep lake,and every distal subaqueous fan formed by gravity flow can be divided into inner-,middle-and outer fans.The cross-facies transported sands which are sourced from higher-sand-content major sands of delta front can form high quality reservoirs with an average porosity of 15.1％ and geometric average permeability of 5.1×10-3 μm2.The main channel and distributary channel of distal subaqueous fan are the most favorable exploration zones.%基于地震、测录井、试油、岩心及分析化验资料,以渤海湾盆地歧口凹陷板桥—歧北斜坡区古近系沙河街组一段下亚段滨Ⅰ油层组为对象,开展层序划分、深水沉积相特征及模式分析,研究深水重力流规模性发育原因、储集层物性特征及主控因素,提出深水区有利储集相带的划分标准和预测方法.研究表明沙一下亚段滨Ⅰ油层组自下而上可划分为3个厚度在百米之内的五级层序;斜坡深水区沉积了一套远岸水下扇型重力流沉积,发育主水道、分支水道、水道侧缘、水道间泥及无水道区浊积席状砂等微相类型,空间上具有区域性多期多级的继承性和建设性发育特征,为扇三角洲—远岸水下扇—深湖相沉积序列,每一次重力流事件形成的远岸水下扇都可以划分为内扇、中扇和外扇3个亚相类型.以含砂率较高的扇三角洲前缘主砂体作为供给物源的“跨相搬运”砂体可形成优质储集层,孔隙度平均为15.1％、渗透率几何平均值为5.1×10-3 μm2.明确了远岸水下扇主水道及分支水道分布区是最有利的勘探区域.
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