Detailed tectonic geomorphology of the Dras fault zone, NW Himalaya

Abstract

<abstract> <p>Our recent mapping of the Dras fault zone in the NW Himalaya has answered one of the most anticipated searches in recent times where strike-slip faulting was expected from the geodetic studies. Therefore, the discovery of the fault is a leap towards the understanding of the causes of active faulting in the region, and how the plate tectonic convergence between India and Eurasia is compensated in the interior portions of the Himalayan collision zone, and what does that imply about the overall convergence budget and the associated earthquake hazards. The present work is an extended version of our previous studies on the mapping of the Dras fault zone, and we show details that were either not available or briefly touched. We have used the 30 m shuttle radar topography to map the tectonic geomorphological features that includes the fault scarps, deflected drainage, triangular facets, ridge crests, faulted Quaternary landforms and so on. The results show that oblique strike-slip faulting is active in the suture zone, which suggests that the active crustal deformation is actively compensated in the interior portions of the orogen, and it is not just restricted to the frontal portions. The Dras fault is a major fault that we have interpreted either as a south dipping oblique backthrust or an oblique north dipping normal fault. The fieldwork was conducted in Leh, but it did not reveal any evidence for active faulting, and the fieldwork in the Dras region was not possible because of the politically sensitive nature of border regions where fieldwork is always an uphill task.</p> </abstract>