Morphostructural approach in predicting the geomorphic attributes of Vigodi Fault, Kachchh, Western India

Abstract

This study analyzes geomorphic landforms and drainage patterns to assess the neotectonic activity of the NW-SE oriented Vigodi Fault (VF). The VF lies in the western flank of the Kutch Basin, which shows typical wrench geometry. The fault zone comprises, a complex zone of compressional and extensional fault segments, collectively form the Vigodi–Gugriana–Khirasra fault complex. The fault zone encompasses various neotectonic landforms such as terraces underlain with bedrock (strath) on the upthrown block and fill sediments on the downthrown block, fault scarps, warped Quaternary sediments, and slot canyons within Quaternary sediments, river knickpoints, and deflected rivers. The presence of strike- and dip-parallel slickensides within the VF zone indicates oblique slip motion of the fault. Furthermore, we extracted conventional morphometric parameters from the river network and calculated the river gradient length anomaly (GLA) to determine the variability of fault activity across the strike of VF. The observed values of GLA correspond to the long-term uplift and subsidence associated with the VF. The results of our geomorphic and morphometric analyses show that the area is neotectonically active. The combined observations made from the present investigation can be used to estimate the seismic hazard and mitigation planning of the study area.