济阳坳陷构造演化特征

盆地的形成和演化与板块运动有密不可分的关系 ,可以说中国陆相盆地的形成和演化是古生代以来板块运动的必然产物。济阳坳陷属于渤海湾盆地的一部分 ,所以研究其演化特征必须要了解渤海湾盆地的形成。济阳坳陷所处的区域在不同时代有不同的特征。古生代华北板块总体上以升降运动为主 ,但由于北缘长期处于活动大陆边缘状态 ,东南缘又经历了多阶段的板块构造演化 ,其开合作用造成了华北内部地壳较弱的挤压变形 ;中生代的裂前拱起和初始断陷阶段 ,济阳坳陷已初具雏形 ;新生代是济阳坳陷的强烈构造运动阶段 ,此时板块运动形成了盆地大体框架后 ,经过地幔波状运动的内部改造便形成了当今四凹六凸“北断南超”的箕状断陷盆地

CHARACTERS OF TECTONIC EVOLUTION OF THE JIYANG DEPRESSION

The formation and evolution of a basin is correlated with the movement of plates. So the authors consider that the formation and evolution of the Chinese inland basins are the necessary result of plate movements since Paleozoic. The Huabei plate solidified after the Fuping movement. The Luliang movement ended the formation of Huabei plate and formed th old uniform and steady Chinese Plate. The Jiyang depression is one part of the Bohai Bay basin. One must know the formation of the Bohai Bay basin if one wants to learn the character of Jiyang depression's tectonic evolution. The Jiyang depression has different characters in different times. In Paleozoic, the Huabei plate was mostly the rising motion and the descending motion, but, because its north edge was in the state of activity and its southeast undergone many times of tectonic evolution, the movement brought about the slight distortion of the Huabei inner crust. In Mesozoic, the Tanlu fracture and Luxi heave played an important role in the evolution procession of the Jiyang depression. In this time, the Jiyang depression formed its basal ambit. In Cenozoic, the Jiyang depression was in the phase of strongly tectonic movement and formed the block frame. Then, after the undulate movement of the earth mantle, it became the fault depression basin which has four sags and six lobes now.