CASPIAN MOLLUSKS IN THE KARANGATIAN BASIN OF THE BLACK SEA (THE LATE PLEISTOCENE)

Abstract

Biostratigraphic analysis of the cores from the Black Sea shelf in the northeastern part of the basin showed that the exposed Karangatian deposits contain shells of Didacna cristata and Didacna subcatillus mollusks in their upper part. The didacnae are of Caspian origin: they are characteristic species of the Hyrcanian transgressive basin that developed in the Caspian at the beginning of the Late Pleistocene. Mollusks migrated to the Karangatian Basin of the Black Sea through the strait that opened in the Manych Depression when the level of the Hyrcanian transgression overreached the threshold of the Manych runoff. The waters of the strait flowed into the Karangatian Basin in the final phase of its development when the sea level was lower than nowadays and salinity didn’t exceed 18‰.