The Research Of Large-scale Framework Reef Of Late Carboniferous Of Ziyun, Houchang In Guizhou

By the effect of Frasnian-Famennian extinct and the ice age in the south hemisphere, there is few reefs in the carboniferous, and the research about the reefs in the carboniferous are centralized on some algae, the research on the metazoan framework reefs is comparatively weak.A large-scale of framework reefs is found in Houchang Town of Ziyun city in Guizhou province. The reefs lies in the Triticites zone of Maping Formation and formed in the late stage of late Carboniferous, Fomitchevella is a kind of new discovered reef-building biology of late carboniferous,it is a familiar kind of colony tetracoral, other reef-building organisms are Phylloid algae, Ivanovia cf.manchurica, cyanobacteria It forms the colony framework like pipes by buding, there are two types:lateral multiplication and central multiplication.The large-scale of assemblage reefs develops at the margin of carbonate platform, as the influence of change of environment, the reefs-building community changes clearly in the reefs.By the research of the reefs, it is divided into 2 growth stage,4 communities from lower to upper portions. The reef-building communities are Ivanovia cf.manchurica, Phylloid algae, cyanobacteria and colony tetracoral Fomitchevella community. The three formers grew individually in various environments and formed dot-reefs in parallel mode. The latter formed upper major reef by large phacelloid Fomitchevella. These communities represent different developing stages of the reefs and reveal biologic succession features of the reefs in the reef-building process. There is a consistent and corresponding relation that controlled the growth of distribution of the reefs between the evolution of communities and the reef-building process.The process of the large-scale of framework reefs is:formed in different platform margin environment on the bioclast beach, the reef-building community builded by cyanobacteria, Ivanovia cf.manchurica and Phylloid algae formed the dot-reefs layer. Along with the changing of enviroment, Fomitchevella replaces the underpart community, the first development of Fomitchevella begins. But as Fomitchevella growing decentralized and no forms the reef-building community, so the development of Brachiopoda restricts the living space of Fomitchevella,at last,most of spaces are took up by Brachiopoda,so Fomitchevella doesn't joint together and the reef-building fails. At the evening, Fomitchevella fixes up centralized, develops around, takes large spaces and formed the reef-building community base on Fomitchevella. Then Fomitchevella develops exceeding under steady entironment and builds the unusual large coral framework reefs of Carboniferous finally.By the research of the large-scale of framework reefs in Houchang Town of Ziyun county in Guizhou province, we found that their model of growth, development and structure characterized by Fomitchevella communities are very different from other reefs of late Carboniferous in China and the world. The discovery of Houchang Town of Ziyun county in Guizhou province reefs increases biological types of Carboniferous communities in the world. It offers a new example for evolution of reef-building community and reef growth.