Diagenesis and Diagenetic Facies of Reservoir in He8 Section of Shihezi Formation in EastII Part of Sulige Gas Field

According to the results of experimental methods such as polarizing microscope,scan electron microscope and cathode luminescent,and previous published research results,the characteristics of diagenesis and diagenetic facies of reservoir in He8 section of Shihezi Formation in east Ⅱ part of Sulige Gas Field were studied.Meanwhile,the test results of fluid inclusions were also considered.The diagenetic evolution was divided into four stages including six phases.In the process of diagenetic evolution,the dissolution in late period B of early diagenetic stage to early period B of middle diagenetic stage is so important that produces lots of secondary pores,and because of the dissolution,this stage is the key time to form constructive diagenetic facies.According to the study of petrology and diagenesis,there were five diagenetic facies types,and the logging characteristics of each diagenetic facies were set up.After analyzing the diagenetic facies of single well,diagenetic facies in vertical are characterized by dissolution facies in the below and compaction facies in the upper,and the plane distribution is confined by sedimentary facies.The dissolution facies of unstable components of sandstone with low pore and permeability are the most constructive facies which distribute isolatedly.