摘要
通过区域地质构造特征分析、野外露头观察、区域地震大剖面构造解释、钻测和非震资料的综合研究,认为南缘山前带中生代为伸展坳陷、新生代为走滑压扭坳陷,不具备典型前陆盆地的特征。南缘构造发育期次多,构造形态定型晚,盆缘构造边界为多期断裂组合、断层与不整合联接的复合体,具有拼合、立体断裂体系特征,综合划分为4层复合边界结构,解释为4段式复合边界结构类型。利用编制构造发育剖面的方法近似定量的估算了盆地南缘褶皱带在不同地质时期的挤压收缩量以及中新生代总的挤压收缩量,构造演化特征对沉积盆地具有明显的沉积控制作用。
Combined with the analysis of characteristics of regional geological structure, outcrop observation, regional seismic profile structure interpretation, drilling, logging and non-seismic data, the characteristics of structure evolution and its sedimentary response have been studied. The results show that the fore mountain belt at south margin of Junggar basin was an extensional depression at the Mesozoic, and was a strike-slip compressive depression at the Cenozoic, but do not have the characteristics of the typical foreland basin. Also it experienced times of development phases and the structure features formed later. The basin tectonic boundary is the complex of multiphase fracture combination, and the composite of fault and unconformity, which had the characteristics of split and three-dimensional fracture system. It could divide into four layer composite boundaries, which are interpreted as four sections of composite boundary structure type. At last the extrusion shrinkage in different geological periods and the total extrusion shrinkage in Middle Cenozoic were approximate and quantitative calculation at the southern margin of the basin fold belt by using the method of preparation of structural development section. The structural evolution characteristics effectively controlled the sedimentary of the basin.
