Study On The Quaternary River Landscape In Yabrai Mountain, Alax Area, Inner Mongolia

Alxa Area has poor natural condition, much desert and poor population. Althoughformer research is much, but the related quaternary river landscape research is relativelysmall, and is lack of accurate age data. The subject of this study is the quaternary riverlandscape which is located in Yabrai Mountain Alxa Area of Inner Mongolian AutonomousRegion. We analysis the features of the river landscape, invert the evolution process of theriver landscape, and construct the relationship between this evolution process and the newtectonic movement. The main results include:The quaternary river landscape in the study area mainly includes the early pleistocenesediment and river terraces. The early pleistocene sediment formes in the period of earlypleistocene and the river terrace forms because the river downcut. we analysis the features ofthe river landscape. we compare the features of different river landscape,the features of theriver landscape in different periods of tectonic activity, and the features of the river on thelongitudinal. Finally,we find the spatial distribution of the river landscape in the study area.The river terraces in the study area is divided into five terraces, and we find the evolution process of the river landscape. There are six types of evolution process of theriver landscape. No.1, Qp1,1510~1036kaBP, the early pleistocene sediments formed,characterized by flat platform on landscape; No.2,Qp2-1,771~739kaBP, T5terraces formed;No.3, Qp2-2,210~188.2kaBP, T4terraces formed;No.4, Qp3-1,123~121.9kaBP, T3terraces formed;No.5, Qp3-2,74.3~11.9kaBP,T2terraces formed;No.6,Qh,11.7ka tonow,T1terraces formed.The relationship between the evolution process of the river landscape and the newtectonic movement is close in the study area. Tectonic movement causes the uplift of theground, and is the important factor of the formation of the river landscape.The riverlandscape in the study area has a wide range of responses to the new tectonic movement.Different rivers in the study area affected by the new tectonic movement in the same tectonicactivity period are different. Different sediments in the same river affected by the newtectonic movement are different.