Geospatial assessment of active tectonics using SRTM DEM-based morphometric approach for Meghalaya, India

Abstract

Meghalaya, situated over the Shillong Plateau in the northeastern region of India, is considered a seismo-tectonically active region because of the Indian-Eurasian convergence and rising since the Cenozoic era. The present study aims to identify active deformation zones due to tectonic activity following a morphometric approach. Based on DEM data and GIS techniques, morphometry parameters along with geomorphic indices are obtained which allows the analysis of geomorphic processes responsible for the region’s landscape evolution, and indices of relative active tectonics (IRAT) are calculated by combining them. High drainage density, larger ruggedness number, intermediate to high hypsometric integral values with S/convex-type hypsometric curve, lower valley floor width-to-height ratio and stream sinuosity index values suggesting the region is tectonically active and according to IRAT, the Khasi and Jaintia Hills region (the central and eastern part) of the Meghalaya possesses relatively higher tectonic levels. The variation of tectonic activity is not uniform in the same structural feature and is found to be lower in the western portion and higher towards the east along the same Dauki Fault.