关键词: 构造演化, 地堑, 渤海湾盆地, 早第三纪, 含油气系统

Abstract: Owing to the extension and strike slip action,there were five basic types of the structural styles during the Palaeogene in Bohai Gulf Basin.Non rotational graben,rotational half graben,rollover half graben and strike slip graben were major structural styles in Paleocene and early and middle Eocene.Rollover half graben,half graben and ramp sag were major in late Eocene and early Oligocene.Rollover half graben,half graben and ramp sag,strike slip graben were major in middle and late Oligocene.The evolution of the structural styles follows three orders including rotational half graben→rollover half graben→half graben and rap sag,non rotational graben→rollover half graben→half graben and ramp sag,and non rotational graben→strike slip graben.The orders with difference within each are controlled by the faults action in different areas.Later two orders take place along Tanlu fracture belt,Cangdong Lanliao fracture belt and Taihang east fracture belt which are three strike slip belts in the lithosphere.The first order occurs in two extensional areas between two strike slip belts.The evolution of structural styles have clo ser relations with the characters and distributions of the petroleum source rocks,the oil and gas pools,and the petroleum systems.

Key words: tectonic evolution, graben, Bohai Gulf Basin, Paleogene, petroleum system