Sediment dispersal in the macro tidal Gulf of Kachchh, India

Abstract

Studies of sub-bottom physiography, tidal parameters and characteristics of the sediment in the Gulf of Kachchh have been made. The tidal range becomes progressively higher in the inner gulf with associated high magnitude currents. The bathymetry of the inner gulf is marked with U and V shaped cuttings extending in the parallel clays, deposited in an earlier phase of deposition. In the outer gulf, there exists a palaeo-channel, buried under 18 m thick sediments (in the central region). Existence of this channel manifests to the change in the environment of deposition in the gulf, in the recent past. Based upon the physiographic, granulometric and clay content variations, and prevalent hydrodynamic regime in the gulf, the sources of the sediments and their dispersal patterns have been determined and presented. The results of the study have application for sequential interpretation of satellite images for separating out macro-tide induced temporal and spatial changes in the dispersal patterns and physiographic changes in the Gulf of Kachchh.