FABRIC ANALYSIS OF GRAVEL IN QUATERNARY GRAVEL BEDS ON BACKBONE AREA OF NIQINGTANGGULASHAN MOUNTAINS

The authors expound the source, the origin and the transport of different original Quaternary gravel beds in south and north of Nianqingtanggoulashan Mountains, from the bedrock strata, the compositional, the granulometric and the psephitic analysis, based on fabric analysis of Quaternary gravel beds on backbone area of Niqingtanggulashan Mountains. It is obvious difference in the rock composition, the grain sizes, the sphericity, the intensity of weathering on the 3 Gravel Beds of glacial epoch phases in the middle section of Nianqingtanggoulashan Mountains. This difference reflecs the denudation of the different rocks of Nianqingtanggoulashan Mountains in the doming of Qinghai-Xizang (Tibet) plateau.