Abstract:

The Permian System in Sichuan basin is composed of shallow water carbonate rocks deposited on a platform in a warm and humid climate with very flourishing biota.Dolomitization occurred under the following circumstances:(1)replcement by large coarse-grained dolomites along the fractures and pores;(2)replacement by small rhombohedral dolomites along the suture lines and(3)replacement by large coarse-grained dolomites of fresh-saline water origin.The last mentioned dolomites predominate the other two,with the ancient carbonate rock upland of biolith origin in neighboring provinces playing the controlling role.

摘要：

四川盆地二迭系是一个气候温暖、潮湿、生物极端繁盛的浅水碳酸岩台地。其中的白云化有三种成因:一是沿缝孔交代的粗大的白云石;二是沿缝合线交代的小菱面体的白云石;三是咸淡水混合成因的粗大的白云石,前两种数量不多,后一种却形成了大规模的云岩体,其控制因素是生物滩或生物礁等古代碳酸岩高地。