FEATURES OF THE DIAGENETIC AND RESERVOIR OF PERMIAN ORGANIC REEF IN SOUTHWEST GUIZHOU PROVINCE

The Permian organic reef in Southwest Guizhou Province began to be formed in the middle-late Maokou age of Early Permian and continuously developed until Late Permian.The organic reef may be considered as a kind of margin-plat form reef.The reef-building zoolites were chiefly Spongia and Hydrozoa, secondly Tabulate and Bryozoa. However, Cyanophyta which played an important part in the process of reef-building took shape of’ cohesion and encrustation in appearance. There were also some commensaliam in the reef，such as Crinoidea, Brachyopoda, Foraminfera, Fusulinids, Gastriopoda,Chlorophyta and so on.They correspondingly formed frame- building rocks, frame building obstructed rocks, obstructed Fucks, cohesive rocks and bioclastic limestone,