Mid-Holocene sedimentation and landscape evolution in the western Great Rann of Kachchh, India

This study is an attempt to reconstruct the history of sedimentation and landform evolution in the western Great Rann of Kachchh. Field stratigraphy, sedimentology, geochemistry, optical and radiocarbon dating suggest dominance of tidal flat sedimentation with subordinate contribution coming from the southern-draining streams during 5.5 to 2 ka. Variability in the geochemical proxies are interpreted as a surrogate for tidal energy (viz. Zr and Cr) which, along with the major elemental ratios (TiO2/Al2O3 and K2O/Al2O3), indicate enhanced tidal energy condition during 5.5 to 5 ka and around 3 ka. A close correspondence of the major and trace elements with those of the Indus River sediment and the dominance of illite suggest the Indus River was a major contributor for western Rann sedimentation during the mid-Holocene. These sediments were routed through the Kori Creek during marginally high sea level until around 2.2 ka and the present landscape was largely sculptured after the 1819 Allah Bund earthquake.