An analysis of relative active tectonics based on DEM

Geomorphic indices are useful tools for studying relative active tectonics.This paper presents a new method for evaluating relative active tectonics based on DEM data,using several tectonic geomorphic indexes which include hypsometric integral,drainage basin asymmetry,stream-gradient index,mountain-front sinuosity,valley floor width – valley height ratio,drainage basin shape etc.Iat is an index of relative active tectonics,which is obtained by the average of the different classes of geomorphic indices.The authors divide them into four classes: low,moderate,high,and very high from relatively low to the highest tectonic activity.Exemplified by the upstream region of the Weihe River,the authors consider the drainage is relatively higher tectonic activity(Iat=1.50),and that the method has ideal effects and significance for exploring diversities of relative tectonic activities on an areal basis.