胜坨油田二区沉积微相特征与剩余油分布

以岩心分析和测井解释为依据 ,对胜坨油田二区沙河街组沉积微相与剩余油分布进行了研究。研究结果表明 ,胜坨油田二区沙河街组二段发育典型的河控三角洲沉积 ,其中 7砂层组为三角洲平原沉积 ,发育水下分流河道、天然堤、分流间湾微相 ,各小层及韵律层网状河道特征明显 ;8砂层组为三角洲前缘沉积 ,发育河口砂坝、远砂坝微相 ,每个韵律层从岸向盆地依次出现坝顶部、坝主体和坝侧缘及远砂坝。在本区 ,沙河街组二段沉积微相控制了油藏的剩余油分布 :在纵向上 ,剩余油主要富集在分流河道的中上部、河间薄层砂体和河口砂坝中下部 ;平面上 ,剩余油富集在河道边缘、坝侧缘、坝顶部的砂层中

Sedimentary micro-facies and remaining oil distribution in the second district of Shahejie Formation in the Shengtuo Oilfield

The properties of sedimentary microfacies and remaining oil distribution were analyzed on the core analysis and log interpretation. The second section of Shahejie Formation in the second district (Es\-2) in Shengtuo Oilfield developed the typical fluvial dominated delta deposition. The seventh sand group of Es\-2 is of the delta plain deposition and has developed underwater distributary river course, levee and interdistributary bay microfacies. The characteristics of braided river course in every substratum and rhythmic bedding are distinct. The eighth sand group is of the delta front deposition and has developed debouch bar and far bar microfacies. The bar top, bar host, bar side and far bar in rhythmic bedding appeared from shore to basin in turn. In this area, the distribution of remaining oil was controlled by the distribution of sedimentary microfacies in second section of Shahejie Formation. The remaining oil was mainly distributed in the middle and upper parts of distributary river course, the middle and down parts of inter channel thin sandstone and debouch bar in vertical. The remaining oil was distributed in the sandstone of river edge, the side and the top of bar in plane.