关键词: 浅水三角洲, 　喇萨杏地区PⅠ组, 　沉积相划分

Abstract: In view of the gradual change zone between the sub phases of shallow water delta，it is difficult to demarcate accurately the boundary position and meet the demand for oilfield development. In order to achieve the purpose of demarcate accurately sedimentary facies，according to sedimentary dynamics theory of shallow water delta， the identification sign of sedimentary facies is established by making use of the data of core analysis and well⁃logging of dense well pattern， and analyzing the plane evolution of facies indicator. Distributary plain is characterized by onshore stream sedimentation，inner front surfaces is characterized by combination of underwater distributary channel and sheet sand，outer front surfaces is characterized by contiguous thin sheet sand.The method of dividing facies belt boundary of "core locating and microfacies locating" has been established， and the reasonable definition of sedimentary facies zones is realized，which has laid a solid foundation for reservoir classification, reserves calculation and development planning .

Key words: Shallow water delta, PI formation in La?Sa?Xing area, Sedimentary facies division