贵州紫云晚二叠世生物礁及其演化

NATURE AND EVOLUTION OF LATE PERMIAN REEF IN ZIYUN,GUIZHOU PROVINCE

Ziyun Late Permian is a typical barrier reef developed in the Southern Guizhou and Northern Guangxi. The main feature of Ziyun reef is discussed as the following.According to rock compositions and structures, seven types of rocks can be recognized in Ziyun region. They are silicalite stone, sphinctozoan framestone, sponge bafflestone, algae/sponge bindstone, Permocalculus and Foraminifera packstone, bioclastic packstone and dolomitite. Several reefbuilding organisms were found in Ziyun reef. The principal framebuilders are sphinctozoans, including 7 genera ,11 species. And other reefbuilders are Inozoan, Tabulozoan, Tubiphytes and Archaeolithoporella, and rare Hydrozoa and coral. On studies of the reef evolution, Ziyun reef can be divided into five cycles, which developed from core-reef to back-reef.