The Mesozoic-Cenozoic Structural Characteristics And Its Evolution In Southern Ordos Region

Southern Ordos region is up to the Ordos Basin in the north, to North Qilian-North Qinling tectonic belt in the south, to Liupanshan tectonic belt in the west, and to Fenhe rift in the east, which include Weibei uplift, Weihe graben, Xiaoqinling structural belt and other tectonic units.Now the characteristics of geological structure in the area are very complex, because the area was reformed by multi-period of tectonic movements and composite overlay of different stages and different characters. The research on the Mesozoic-Cenozoic structural characteristics and its evolution in Southern Ordos region can provide theoretical basis and detailed information for the Mesozoic-Cenozoic oil and gas exploration in the Ordos Basin.Using the principles of continental dynamics and basin analysis theory, based on tectonic, geophysical, observations of field geological section, combined with the explained of seismic profiles and the preparation of the Mesozoic-Cenozoic phases ancient structural maps, researching the Mesozoic-Cenozoic structural features superposition of different tectonic stages, the ownership of the tectonic, the framework of the tectonic, sedimentary characteristics. Form different scales, different levels to research the Mesozoic-Cenozoic structural characteristics and its evolution in Southern Ordos region.Based on previous research, the region showed only tectonic uplift in Indo Chinese epoch, and the degree of tectonic deformation was relatively weak. Yanshan epoch was the main period of the tectonic deformation in Southern Ordos region,.the region of interest not only inherited and strengthen the tectonic features of Indo-Chinese movement, and formed relatively complete folded thrust fault. The region was in the strike-slip and extensional tectonic setting in Himalayan epoch, formed the half and faulted Weihe basin,which was limited by the normal fault.In the end, according to structural stages, sedimentary characteristics, palaeotectonic characteristics, combined with regional tectonic background, the structural evolution of the Southern Ordos region in Meso-Cenozoic are discussed.