塔中4井区石炭系C_I油组储层成岩作用及其演化特征

塔里木盆地塔中４井区石炭系ＣＩ油组为石英砂岩类碎屑岩储层．通过对该区３口井的岩芯、薄片观察及有关资料分析，识别出了压实压溶作用、胶结作用、溶解作用、交代作用及自生产矿物的形成５种成岩作用类型；划分出准同生期、早成岩期、晚成岩Ａ期和晚成岩Ｂ期４个成岩阶段；分析了剖面上的成岩共生序列及各阶段的成岩演化特征，并指出本区在成岩演化过程中至少存在两期油气运聚：一期在早成岩晚期至晚成岩Ａ期之初，另一期在晚成岩Ａ期的末期．

Preliminary Research on Diagenesis and Evolution Characteristics of C_1 Oil Group Reservoir of Carboniferous System in Tazhong-4 Well Area

1 oil group of Carboniferous system in Tazhong-4 well area is elastic rock reservoir of quartzy sandstone. Five kinds of diagenesis have been recognized by the examination of cores and thin sections,and analyses of information concerned from three wells in this area. The recognized diagesis includes compaction and pressure solution,cementation, dissolution,alteration and replacement,and precipitation on anthigenic minerals.The C1 reservoir experienced four periods of diagenesis-penecontemporaneous early diagenetlc, late diagenetic A and telodiagenetic B. Diagenetic evolution features in each period are analysed. It is pointed out that there were at least two stages of migration and accumulation of oil-gas in the process of diagenetic evolution in this area: one was between the late stage of early diagenetic period and the beginning of late diagenetic A period,the other was the last stage of late diagenetic A period. Factors affecting the diagenesis and their relations to the porosity of C1 reservoir are also discussed in the paper.