The Analysis Of Geomorphic Characteristics And Genesis Of The Southern Section Of The Qin Jin Cayon

The Qin Jin Canyon belongs to the middle reaches of the Yellow River,Qin Jin Canyon has always been a hot area of geoscience research.The Southern section of the Qin Jin Canyon refers to the North to Hukou Waterfall,the South to Yu Menkou,this section is about 65 km long.The southern part of Qin Jin Canyon is located in the southeastern Ordos Basin,and the research degree of this area is relatively low.This paper investigates and studies the features of the valley geomorphic features,the river erosion mode,the characteristics of the lithostratigraphy,the joint and the fracture structure and the neotectonic movement in the southern section of the Qin Jin Cayon.And gained the following recognition:By analyzing the geomorphic characteristics of the river valley,especially the features of the Hukou Waterfall,the ten-Dragon trough and the pothole in the Hukou area of the northern section of the study area.It is found that the joints near the Hukou are developed near south-north and near east-west joints,and a variety of river geological product potholes are formed on the bedrock riverbed and the shore platform.Water carries a large amount of sand and gravel to eroded weak parts of rock and promotes the formation of river potholes.Through field observation,practical demonstration and comprehensive research,the cause of macroscopic and microscopic Valley in Valley geomorphic is further confirmed.(1)the great hydrodynamic erosion of the river water is a necessary dynamic condition for the formation of Valley geomorphology;(2)the valley geomorphology is related to the differential erosion of the stratum lithology;(3)The bedrock riverbed develops a large number of joints and reduces the mechanical strength of the rock and accelerates the formation of the valley;(4)the uplifting effect of the neotectonic movement leads to the obvious river cutting action.