Quaternary Sedimentary And Structure Features Of The Hohhot-Baotou Basin, Inner Mongolia

Quaternary is an very important geological period because the sedimentary and structure features of quaternary have close relation with the human survival and developments. The distribution and nature of quaternary sedimentary were controlled by paleoclimate, paleoenvironment and paleogeomorphology, in which the commencement and development of neotectonics plays an important role. Consequently, the studies on the evolutionary and structure features of quaternary sedimentary basin have important realistic and academic significances.The Hohhot-Baotou basin is composed by two hollows and one buried lifts, and the quaternary strata developed completed with facies diversified. From north to south, the facies transformed from pluvial phase to fluvial phase, which staggered contacted with each other. In this paper, the regional stratigraphic units of Hohhot-Baotou basin were compartmentalized detailed particular in upper Pleistocene. According to the current rules to build new stratigraphic unit, new formation including Xinaobao, Haolaigou, Seqiwan, Hulusitai and Guchengwan were firstly defined, in which precise paleontological and geochronological data were used.The consuming neotectonic movement in study area is dominated by radical movements, subordinately with sinistral strike-slip feature. The basement were controlled by faulting, and the depth depressing gradually from north to south. The north side was the center of the subsidence, and on the edge of the basin the faulting is evident. Because of the frequently faulting, the basin is characterized by familiar destructional benchs, torrential deltas and chutes, and the paleoriver diverted commonly. So, the preventatives of induced geological hazard should be regarded such as the earthquake, debris flow and slides.The Hohhot-Baotou basin was developed on the basis of Paleocene sedimentary basin, and in Pliocene large scale subsidence commenced which built the fundation of huge sedimentary strata. The basin was the product of intraplate deformation, whose formation and evolutionary were dominated by the regional stress framework with NS extension and EW strike-slip. The basement of the basin oblique-orientated ranged. The subsidence of the basin is still continuing and affected by the active marginal fault.