Freshwater plume‐like condition near the north‐eastern coastal Arabian Sea during early Miocene: Evidence from the stable isotope record in the growth bands of gastropods (Turritella sp.)

Abstract

The Early Miocene witnessed major tectonic, palaeoceanographic and climatological reorganizations over the Asian realm. The Himalayan and Tibetan plateau upliftment influenced monsoon intensity during this age. Contemporary high‐resolution tropical hydroclimate records are limited. Here, we present an early Miocene sub‐annual stable isotope record from the growth bands of well‐preserved Turritella sp. from the Kachchh basin, Western India. It showed δ13C and δ18O variabilities from −4.83‰ to −1.80‰ and − 7.06‰ to −2.66‰ (in VPDB) respectively. Conventional oxygen isotope thermometry showed an apparent temperature seasonality from 9.3° to 28.1°C. A comparison of the present early Miocene δ18O record with the modern δ18O records in the carbonates from coastal‐estuarine environments of the Indian Ocean confirmed a high freshwater influx into the NE Arabian Sea during the early Miocene, similar to the modern‐day freshwater plume events observed in the coastal region.