Sedimentary microfacies of lower Kexia formation in Liuzhong area of Kelamayi oilfield

Distributional characteristics of sedimentary facies was studied through the analysis of field outcrop, cores and test data in order to analyze sedimentary environment of Liuzhong district in lower Kelamayi reservoir. This paper points out relationship between reservoir property of sedimentary facies and oiliness, provides basis for development adjustment. The sedimentary facies of study area consists of alluvial fan which is mainly middle fan and fan fringe. Middle fan parfacies is divided into water way, braided stream sand island and sheetflood area based on lithology, structure and log presentation. Fan fringe parfacies is divided into runoff waterway and flood spillway. Distributional regulation of microfacies in sedimentary cycle was pointed out. Sandbody in lower part of cycle is continuous, and the sandbody is thick and extensive. Sandbody in middle part of cycle is mainly wideband shape, and the sandbody is thin and narrow. Sandbody in upper part of cycle is mainly strip shape, and the sandbody is thin and narrow. Sheetflood area with poor physical property and strip shape sandbody with low well control degree is the main object to excavate remaining oil.