Research On The Structure And Sedimentary Microfacies In Yikeshu Oilfield

Yikeshu oilfield is located in Zhenlai county of Jilin province. Yikeshu oilfield is developed in 1988, after nearly 27 years of development, the oilfield has entered extra high water cut period. Low degree of oil recovery, low production speed, fast decline of production, bad development effect have appeared in development. The reasons for these phenomena are mainly the unclear subzone division, the big contradiction between layers, unclear structural characteristics of reservoir top surface and the unclear sedimentary environment and distribution of sand.This paper mainly aims at unclear subzone division, reservoir interface structure, sedimentary environment, oil and water distribution rule of Saertu and Gaotaizi reservoir in Yikeshu oilfield. Appling downhole geological logging data, based on the theory of sequence stratigraphy, Using the standard layer controlled phased cycle isochronous contrast method to divide reservoirs. using logging data and perforation data of dense well pattern and comprehensive seismic interpretation results to get structural maps of reservoir top surface in Yikeshu oilfield. Through the analysis of sedimentary background, phase signs and so on, combined with the data in this area, study the characteristics of sedimentary microfacies to determine the reservoir sedimentary type in Yikeshu oilfield. Get the final conclusion that Saertu and Gaotaizi reservoir is deposition for the delta front. Study distribution characteristics of sedimentary microfacies in Yikeshu oilfield on the plane and space. And analsis the process of reservoir sedimentary. Through the study of sedimentary microfacies and structure to study the distribution of remaining oil and distribution of oil and water. Then predict the advantageous areas.Though the research of this paper, we divide Saertu reservoir into five subzones and divide Gaotaizi reservoir into twenty subzones. And get the top surface structure of reservoirs. Identify three sedimentary microfacies types. underwater distributary channel, under water thin layer of sand and underwater between tributary bay. Finally, we put forward suggestions on the location of encryption wells and extension wells and complementary perforation advices.