辽河盆地东部凹陷北段构造样式形成机制

辽河盆地东部凹陷北段新生代盆地具下断上拗的双层结构,是伸展和走滑联合作用的断陷盆地。通过盆地的几何学、运动学、动力学分析表明:东部凹陷的形成可分为断陷期和拗陷期两个不同的阶段。在断陷期的过程中,伸展及走滑作用的影响程度是不同的。断陷早期以伸展作用为主,中期伸展和走滑联合作用,晚期以走滑作用为主。在这种独特机制作用下,不同时期断陷由不同类型的半地堑组成。断陷阶段早期构造样式主要为非旋转或旋转半地堑;中期主要为滚动半地堑及复式半地堑;晚期主要为走滑半地堑;拗陷是新生代盆地萎缩期的构造样式。不同时期构造样式的研究,实际上再现了构造样式的演化史,同时也是含油气系统成藏动态过程的研究前提。 

THE FORMATION MACHANISM OF THE STRUCTURE STYLES OF THE NORTHERN SECTION OF EAST SAG IN LIAOHE BASIN

Cenozoic East Sag of Liaohe Basin consists of double structure and is a fault-depression basin with extending and strike-slipping.There is different tectonic effects in different periods that is to say extension predominated in the early and strike-slip in the late through the research about the geometric,kinematics and dynamics of the basin.Fault depression is composed of different-type half-grabens. Structural style evolution sequence is from non-tilting half-graben to tilting half-graben,structure styles in the early of fault depression,rollover half-graben and half-graben and ramp-sag are in the middle,and half graben and ramp-sag and strike-slipping half-graben in the late.Depression (From N g to now) is the style in the period of Cenozoic rift basin shrinking.The research of different period structure style reproduces actually the history of structure styles evolution.At the same time,it is a precondition of petroleum system about oil pool formation processing.