Causes and implications of Mid- to Late Holocene relative sea-level change in the Gulf of Kachchh, western India

The relict intertidal deposits from the Kharod River Estuary, Gulf of Kachchh, and the distal end of Kori Creek are used to infer the Mid- to Late Holocene relative sea-level (RSL) change in western India. Employing sedimentology, geochemistry, palynology, ichnology, and optical and radiocarbon dating, the study suggests the dominance of fluvial activity between 16.5 +/- 1.6 and 9.9 +/- 0.7 ka. After similar to 7 ka (7.3 +/- 0.4, 6.8 +/- 0.5 ka), the sea level showed a positive tendency until 4.7 +/- 0.2 ka. The tectonically corrected Mid-Holocene RSL change is estimated as 1.45 +/- 0.33 m between similar to 7 and similar to 5 ka. The study suggests that the Mid-Holocene RSL high was due to the meltwater contribution from the Himalayan cryosphere, with subordinate contribution from glacio-isostatic adjustment and crustal subsidence. The Late Holocene tectonically corrected RSL change at similar to 1 ka (1.1 +/- 0.1 ka and 1045 +/- 175 cal yr BP) is estimated as 0.53 +/- 0.43 m. This is ascribed to monsoon wind-driven tidal ingression that might have affected the tidal amplitude positively. The study suggests that the Mid-Holocene RSL change did not play a deterministic role in the abandonment of the Harappan coastal settlements.

Automated summary

The relict intertidal deposits from the Kharod River Estuary, Gulf of Kachchh, and the distal end of Kori Creek were used to infer the Mid- to Late Holocene relative sea-level change in western India. The study suggests that the Mid-Holocene RSL high was mainly influenced by meltwater contribution from the Himalayan cryosphere, while the Late Holocene RSL change could be attributed to monsoon wind-driven tidal ingression.