Pre-Cenozoic groups in the shelf basin of the East China Sea

The study on the Pre-Cenozoic groups in the shelf basin of the East China Sea (ECS) has been carried out based on the data of geology collected in adjacent areas and geophysics and drilling wells obtained in the basin.The Mesozoic group is extensively developed in the shelf basin.It is complete in the southern area of the basin, from Triassic to Cretaceous.The central uplift belt is characterized by Jurassic Cretaceous volcanic rocks.There are marine-transitional Mesozoic group developed in the southern area of the basin, namely, the Taiw an Strait and the vicinity.The biotitic hornblende plagioclass gneisses with a rubidium-strontiumage of 1 680 M a found in the southern area of the basin is the extension of Pre-Sinian metamorphic rocks out cropped in the coastarea of Zhejiang and Fujian Provinces, China, and the gneisses found in the northern area is the extension of Later Preterozoic metamorphic rocks out cropped in the northern Zhejiang Province.During Later Paleozoic, tHe cont inental shelf of the ECS can be a miogeo-syncline which is located to the west of the eugeosyncline extendingalong the eastern margin of A sian continent, so the Later Paleozoic metamorphic strat a may exist in the basin, especially in the eastern depres-sion of it.