摘要
Microbialites, such as microbial mats and stromatolites, have been found in the Lower Triassic Helongshan Formation (middle-upper Smithian)recently in Chaohu area, Anhui Province, East China. Microbial mats mainly consist of cyanobacteria and simpler green algae. Stromatolites, predominating with cyanobacteria, contain a lot of microorganism types. Microbialites, sedimentary features and special minerals suggest that the Helongshan Formation was deposited in quiet shallow environments,the characteristics of biologic evolution during the Early Triassic in Chaohu area and other areas of South China indicate that the development of microbialites in Helongshan Formation might be a signature of the better beginning of environments and biological recovery in Early Triassic.