LATE GLACIAL GREAT FLOOD IN THE BLACK SEA AND CASPIAN SEA

A comparative analysis of the Late Glacial history of the inner basins of Eurasia enables us to suggest an alternative to the Early Holocene Flood that Ryan et al. (1997) thought could be the basis for the legend of Noah’s Flood. At the Late Glacial time (16-13 ka BP; ¹⁴C on mollusk’s shells) a Great Eurasian Basin System (~1.5 million km², ~650,000-700,000 km³) developed due to a climate warming, the melting of the Scandinavia Ice Sheet and massive river discharge. This is supported by freshwater and alluvial sediments (e.g., chocolate clays, loams and sands with a thickness of ca 20-30 m) with endemic Caspian mollusks Didacna, Monodacna, Adacna, and Hypanis widely distributed from the Caspian Sea to the Dardanelles including waterways between the basins. At the beginning (16-15 ka BP), the flood was especially rapid, increasing the Caspian Sea level by 100-150 m, reaching +50 m and pushing the Volga River mouth upstream in ca 1,500 km. The discharge of the large (Volga, Don, Dnieper) and small rivers increased by 2-4 and 20-35 times respectively, causing megafloods. The high speed of the flood can be seen from incising river paleomeanders not filled with sediment. A large amount of water could not be kept in the Caspian depression and was discharged into the Neweuxinian basin (ancient Black Sea) through the Manych-Kerch Strait at a speed 50,000 m³ sec^-1, and from there across the Bosporus to the Sea of Marmara. As a result, the level of the Black Sea increased by 60-70 m and reached a level of approximately -20 m at the end of the Pleistocene. Archeological evidence from the late Paleolithic sites (e.g., Kamennaya Balka, Avdeevo, Byki, and Kapova Cave) suggests that large-scale flooding of the coastal zone by water from the late Pleistocene basins together with river megafloods caused a reduction of available living space and hunting areas, resulting in a mass migration and subsequent increase in population density. The decrease in available food resources per capita affected everyday life of the Palaeolithic people and was likely to have stimulated the transition from hunting and gathering to farming and cattle breeding in the region. Thus, it is possible that this flood affected the Late Paleolithic people so deeply as to form the legend of the Great Flood.