The discovery of Paleodictyon in Upper Triassic Bagong Formation in Dongqu area of Qiangtang basin and its palaeoenvironment significance

Paleodictyon trace fossils were found in Upper Triassic Bagong Formation in Dongqu area of Qiangtang basin. The authors confirmed that they belong to P.(Glenodictyon) Vander Mark. A comparison with relevant information available shows that the palaeoenvironment of Dongqu area in east Qiangtang basin belonged to deep-sea, low oxygen and high salinity flysch sedimentary environment in Late Triassic. The results obtained by the authors are of significance for environmental analysis and lithofacies paleogeographic pattern study.