渤海湾盆地东营凹陷利津洼陷西斜坡沙三下亚段沉积特征——以滨南油田滨648区为例

滨南油田构造上属渤海湾盆地东营凹陷利津洼陷西斜坡,滨648区是一个被断层复杂化、北高南低的背斜断块油藏,主力含油层系为沙河街组三段下亚段,目前处于中低含水、低采油速度开发阶段。在测井曲线标准化处理基础上,利用Direct-Art软件的多井编辑模块,在海拔垂深对比模式下进行地层划分与砂体对比,将研究区沙三下亚段划分为5个砂组、11个小层;滨648井粒度累积概率曲线、C-M图均反映出粗—中粒的高密度浊流沉积特征。研究区沙三下亚段以扇三角洲前缘亚相及前扇三角洲亚相沉积为主,进一步可划分为水下分流河道、水道间、水道砂坝、前缘席状砂以及前扇三角洲浅湖泥沉积微相;油气储集有利相带多集中在水下分流河道及水道砂坝沉积微相中。

Sedimentology of lower section of third member of Shahejie Formation on western slope of Lijin Subsag,Dongying Sag,Bohai Bay Basin: a case study of Bin 648 area,Binnan Oil Field

The Binnan Oil Field tectonically belongs to the western slope of Lijin Subsag, Dongying Sag, Bohai Bay Basin. The Bin 648 area is an anticlinal fault oil reservoir (higher in the north and lower in the south) complicated by faulting. The lower section of the third member of Shahejie Formation is the main oil-bearing series and is in the development stage of medium-low water content and low oil production rate. Based on the standardized processing of logging data, the multi-well edit module of the Direct-Art software was used for stratum division and sand body contrast using the elevation vertical depth contrast pattern. Finally, the lower section of the third member of Shahejie Formation was divided into five sand groups and eleven thin layers. The grain-size cumulative probability curves and C-M chart of well Bin 648 showed coarse to medium size and high density turbidite sediment characteristics. The lower section of the third member of Shahejie Formation is dominated by fan delta front subfacies and pre-fan delta subfacies, including submerged distributary channel microfacies, tributary bay microfacies, channel bar microfacies, frontal sheet sand microfacies and pre-fan delta lacustrine mudstone microfacies. The favorable facies belt for oil and gas reservoirs are the submerged distributary channel microfacies and channel bar microfacies.