塔里木盆地西部碳酸盐岩成岩演化与储层形成关系

塔里木盆地西部碳酸盐岩的地质演化，主要经历了大气淡水成岩环境，海水成岩环境和埋藏成岩环境的改造，形成丰富的储人间类型和4种典型的孔隙结构特征，即溶孔－晶间孔复合型，粒间孔－粒间溶孔型，缝合线－微裂缝型和致密微孔型，大气淡水淋滤溶解作用和各种类型白云岩化作用有利于优质储层的形成，而胶结作用及压实，压溶作用则阻碍了储集空间的形成，奥陶系微晶灰岩和生屑灰岩由于主要经历了海水成岩－埋藏成岩环境的改造，胶结和压实作用特征明显，未能形成有效储集空间，整体属Ⅳ类差储集层，石炭系碳酸盐岩储层特征具有分区性，麦盖提斜坡区的储层物性明显优于巴楚隆起区，这与斜坡区碳酸盐岩遭后期大气淡水淋溶改造有关，古近系卡拉尔组碳酸盐岩经去膏化作用和大气淡水淋溶作用的复合改造，储层整体面貌呈Ⅲ-Ⅰ类的优良储层。

DIAGENETIC EVOLUTION OF CARBONATE ROCKS IN WESTERN TARIM BASIN AND ITS RELATIONSHIP WITH RESERVOIR FORMATION

During the long evolutionary history of the western Tarim basin, the carbonate rocks were reworked under different diagenetic environments, i.e. meteoric, marine and burial diagenetic environment, to form abundant reservoir porosity and four types of pore texture, including dissolution pore-inter crystal pore composite type, intergranular pore-intergranular dissolution pore type, microfissure type and tight micropore type. Leaching and dissolution of meteoric fresh water and various dolomitization are favorable for the formation of high quality reservoir, whereas the cementation and compaction tend to hinder the formation of reservoir porosity and void. Ordovician microcrystalline limestone and bioclast limestone were mainly reworked under marine-burial diagenetic environment, which formed eminent features of cementation and compaction and did not produce valid reservoir porosity. Carboniferous carbonate reservoirs have distinctive zonation, i.e. quality of reservoir distributed in Maigaiti Slope is better than that of Bachu Uplift, and this is mainly due to the leaching of meteoric fresh water in later period. Carbonate rocks of Eogene Karataer Formation were jointly reworked by the gypsum dissolution and meteoric water leaching, so the reservoir here is of high quality in the study area.