Discussion on Basin-fill Mechanism in Oligocene in the Chunxiao Area of Xihu Trough, the East China Sea

Based on drilling data of Chunxiao No.1 well in Chunxiao area, Southern Xihu Trough, and interpreted with sequence stratigraphic analysis of seismic profile, this paper establishes terrigenous basin-fill succession, varieties of sedimentary system and evolution periods of depositional process in Oligocene basin-fills, and briefly discusses various genesis of coarse clastic deposits in the lower part of Huagang Formation.