Quaternary Tectonic History and Terrain Evolution of the Area Around Bhuj, Mainland Kachchh, Western India

The Mainland Kachchh has witnessed several phases of tectonic movements since the formation of Kachchh rift. The structural set up of the area is dominated by two fault systems - an E-W fault system which controls the geomorphic configuration and a NNW-SSE to NNE-SSW fault system which displaces the E-W faults. The Quaternary deposits of the area, alluvial and colluvial fans, channel deposits and miliolites help in categorising Quaternary tectonic activity into two phases. Reactivation of E-W trending faults during Early Pleistocene led to the present landscape configuration and formation of extensive alluvial and coIluvial fans along these faults. The post miliolite phase resulted in movements along transverse faults as evidenced by a very youthful fault scarp morphology and faulting in postmiliolite alluvial sediments along this trend. The mountain front sinuosity values also suggest a younger phase of tectonic activity along the transverse faults. The first order topography and the seismic activity suggest continued tectonic instability of the region.