Diagenesis and Pore Evolution of the Triassic Reservoirs in Cheguai Area, Northwestern Margin of Junggar Basin

Key words: 
• diagenesis

Abstract: Based on core observation, thinsection identification and well logging data analysis, Triassic reservoir physical property, pore type, diagenesis and reservoir characteristics of the main control factors at northwestern margin of Cheguai area, Junggar basin were studied. Fan delta front facies reservoir experienced mechanical compaction, cementation, dissolution metasomatism, various diagenesis, and compaction effect of reservoir characteristics of the main factors. According to diagenesis and authigenic mineral characteristics, it is late diagenetic stage B period that Diagenesis of the Triassic reservoirs in Cheguai Area.With the depth increasing and compaction enhancing, physical properties become bad, which can make the porosity reduces 20%. Zeolite and carbonate cement dissolution can make the porosity is increased up to 3%, total porosity distribution range between 6%~18%, and the permeability distribution in the range of 0.08×10^-3～40.0×10^-3μm². 