EVOLUTION AND TECTONIC CHARACTERISTICS OF THE MESOZOIC BASIN IN DAGANG PROSPECT AREA

The Mesozoic tectonic styles in Dagang prospect area include stretch,compression,strike-slip,adjustment and those related to volcanic rock.The Early and Middle Jurassic tectonic sublayer dominated by compression has the characteristics to develop the Kongxi buried-hill structure;the Jurassic-Cretaceous tectonic sublayer dominated by weak stretch has concurrent fault depressions and basins,and has strong volcanic activities;and the Late Cretaceous tectonic sublayer dominated by weak uplift has limited distribution of basins.The time and space distribution of the Jurassic-Cretaceous basins and their deformational characteristics are related to Yanshan-Qikou-Xingang buried faulted zone and the Mesozoic Cangdong faulted zone.The deformational dynamics is controlled by the compressional settings which are caused by the minor-angle oblique subduction of the Izanagi Plate and the continent-to-continent collision betneen the Yangtze Plate and the North China Plate.