A Study Of Sandstone Reservoir Pore Feature And Diagenesis Of Qingshankou Formation In Yaoyingtai Area

Changling depression is located in the Southern Songliao basin whth the area of 6700 square kilometers whose basement is a halftraben-like syncline. The YaoYingtai area is located in the east high slope of Changling depression and low heave of Da Qingzi in SongLiao basin, Northeast China.Based on the date analysis of casting lamella,scan electron microscope and X-ray diffractions etc, the paper discusses the characteristic of reservoir petrology and diagenesis. The reservoir rock is mainly composed of siltstone and arkosic arenite. the diagenesis belong to the "A-B" late diagenesis of sandstone reservoir on Qingshankou. The main diagenetic types of the reservoir are compaction, cementation, metasomatosis, denudation and fracturing, the compaction and cementation destroy the primary-texture of pore intensively, dissolution and fracturing change the pore structure effectively. The belt of secondary pore is controlled by the diagenetic facies distribution of compaction, cementation, denudation and fracturing, the evolution of pore is affected by the diagenesis. The main pore types are both fractures and corroded secondary pores whose distribution have the strong heterogeneity. The pore combination type of sandstone reservoirs are divided into four types: the combinations of macroscopic pore, the combinations of microcosmic pore, the combinations of compound pore and the combinations of compact pore. The development of pore directly influences the physical property and the heterogeneity of sandstone reservoirs. The favorable sandstone reservoirs is mainly located in the north of YaoYingtai area.Study on the sandstone reservoir pore feature and diagenesis, the paper analyzes the main affecting factors of reservoir capability, the researched result will provide a scientific basis for further analyzing the oil accumulation and oil-water distribution of this area. It is very helpful for the exploration and progressive development of oilfield.