Geomorphic evidence of late Quaternary displacement of the Karakoram Fault in Nubra and Shyok valleys, Ladakh Himalaya

Abstract

The present study ascertains the spatial variability in the extent of activity of the Karakoram Fault (KF) in Nubra and Shyok river valleys (Karakoram), which was known to be active during the Holocene. Towards this we have used conventional morphometric indices supported by geomorphological observations on the pattern of alluvial and bedrock streams, alluvial fan geometry and moraines. The right lateral displacement associated with KF is geomorphologically expressed by the lateral deflections of the bedrock and alluvial streams toward northwest-southeast as they cut across the Fault. Indirect age estimates inferred based on slip rate of KF suggest that the deflection of bedrock streams with prominent shutter ridges is the cumulative expression of activity of KF since the middle Pleistocene, which continued till the late Holocene.