Stratigraphic Section Description and Division of Middle Permian Baliu Formation, Gonggeng Area, Mojiang, Yunan Province
摘要
Recent investigation on the biostratigraphy of the Mojiang region in Yunnan Province yielded abundant Fusulinid fossils from the Middle Permian Baliu Formation. According to the distribution of Fusulinids on the formation, four fusulinid zones established in ascending order are as follows: Pseudodoliolina ozawai Abundance Zone, Schwagerina ex gr.cushmani-Pseudofusulina radioflucta Assemblage Zone, Pseudofusulina radioflucta-Neoschwagerina kwangsiana Interval Zone, and Neoschwagerina kwangsiana Range Zone. The research have made recently combined with the chronological strata data of Baliu Formation, the above four Fusulinid Zone indicates that Baliu Formation as a lithostratigraphic unit is different from the chronostratigraphic one and spans Qixia Formation and Maokou Formation (Middle Permian).