The Khvalynian transgressions and early human settlement in the Caspian basin

Radiocarbon dates for both Lower and Upper Khavalynian transgressions fall in the timespan between 10 and 17 ka BP, with 13.6-11.8 ka BP, as the most probable age. This transgression supposedly proceeded as a rapid succession of sea-level fluctuations. The initial emergence of Mousterian industries in the Caspian basin as indicated by the Volgograd site, might be correlated with a mild interval preceding the Atelian regression, which was broadly contemporaneous with the Last Glacial maximum (25-18 ka BP). The subsequent expansion of Mousterian sites was largely coeval with the Khvalynian transgression. Supposedly, specific environments that arose in the Caspian basin favoured a prolonged conservation of the Mousterian technique, and, possibly, a survival of Neanderthal populations. A possible factor is a 'cascade' of Eurasian basins that included the Caspian-Black Sea 'spillway', which effectively isolated the Caucasian-Central-Asian area.