RESTORATION OF PROTOTYPE BASINS OF LATE CRETACEOUS TAIZHOU PERIOD IN THE NORTHERN JIANGSU BASIN

Based on studies of regional seismic profiles and conglomerate distribution characteristics,original deposition boundaries of the Northern Jiangsu Basin during late Cretaceous are confirmed.Researches of heavy minerals distribution,sandstone thickness changes and connected profiles of wells have found out sedimentary sources.Combining seismic facies and single-well facies,sedimentary facies of the region are restored;hence the prototype basin is also restored.When the 1st member of Taizhou Formation of Upper Cretaceous is deposited,the Northern Jiangsu Basin is divided in to the Dongtai Depression and the Funing Depression by the Jianhu Uplift.Uplifts in the 2 depressions control sedimentary thickness.Sedimentary materials come from the Tongyang,Lusu and Jianhu Uplifts.When the 2nd member of Taizhou Formation is deposited,the Northern Jiangsu Basin is an integrated basin.The east of the basin is dominated by lake facies and the west by fluvial and flood plain facies.Sedimentary materials come from the Tongyang and Jianhu Uplifts,yet the amount is relatively smaller.