Late Pleistocene to Holocene paleoenvironmental changes in the NW Black Sea

Abstract

ABSTRACT Two gravity cores that penetrated Upper Pleistocene to Upper Holocene sediments in the NW Black Sea have been studied lithologically and microfaunally. The investigations have been coupled with isotopic, calcium carbonate and radiocarbon dating. Six ecological intervals have been distinguished based on changes in microfossil assemblages, giving new insights on the sea‐level and paleoenvironmental changes that took place in the last 25 000 a BP. For the Last Glacial Maximum the ostracod community contains a homogeneous brackish assemblage dominated by Candonidae, suggesting a salinity around 5–8‰. The salinity decrease (to 0.5–5‰) that started concomitantly with the first Meltwater Pulse during Heinrich Stadial 1 is mirrored by increasing diversity and abundance of microfaunal assemblages. This microfaunal increase reached maximum values within the Bølling–Allerød warm period. The shift from Loxoconchidae to Candonidae towards the top of the Younger Dryas suggests a slight increase in salinity. The Preboreal warming period is marked by an abundance increase of ostracod assemblages. During the Late Holocene, stable marine conditions set in, reflected by assemblages similar to those of the present‐day. Based on these data, the first marine influx into the Black Sea before 9390 a BP is assumed.