IDENTIFICATION OF MORPHOTECTONIC FEATURES OF DEHRADUN REGION BASED ON REMOTE SENSING AND GIS

Abstract

The Dehradun region lies in the Northwest Himalayan foothills and it is seismically active zone. It is bounded by HFT in south and MBT in north, two prominent rivers Ganga and Yamuna flow across these faults, which is not yet clearly visible in the landscape. Active fault displacement can affect river morphology. Objective of the present study is to identify morphotectonic features in the area. These morphotectonic features can helps in reconstructing the tectonics of the area. For this study we collected satellite images and DEM data from USGS and performed several operations to process them using ERDAS imagine and ArcGIS. Remote sensing and GIS techniques are used to identify these morphotectonic features. We selected two different locations along Ganga and Yamuna each. These river system shows clear significant geomorphological changes in the Dehradun valley and Mohand Anticline as they flow into the l-limalayan foreland. We observed that the elevation of the Yamuna River decreases relatively systematically along the Dun region after crosses the MBT. The elevation decreases at a uniform level through the Dun region and decreases at a faster rate through the Mohand anticline. Both Ganga and Yamuna Rivers are controlled by Ganga tear fault and Yamuna tear fault respectively. The changes in width channel belt and braiding indicating there is an active uplift on the HFT.