Some Features of Hydrological Processes in the Ponto-Caspian Seas During the Late Pliocene—Early Pleistocene

Abstract

AbstractThe present theory of the transgression mechanism of the Caspian Sea in the Akchagylian time is based on the hypothesis that the water for transgression came from the ocean. But, this hypothesis is unacceptable because the sea level was supposed to have risen above the ocean level. In addition, if the salty ocean water had flowed into the closed Caspian Sea for a long time, the salinity of the sea water would have increased to the brine concentration, the wildlife of the sea would have died, and a layer of evaporites would have been formed at the bottom. The calculation of the sea water salinity with salty ocean water showed that the salinity of the sea water would have increased annually by 0.12‰. Consequently, after 1000 years, sea salinity would have been 120, which would lead to an ecological catastrophe with the formation of evaporites. The comparison of the calculation results with the geological studies results showed that in the period of Akchagyl tangression, there was not a single sign of prolonged influx of salt water into the sea and could not be. Consequently, the Akchagylian transgression of the Caspian Sea, like all other transgressions, was created by the fresh water resulting from the melting glaciers. Theoretically, there is evidence of melting glaciers (Svitoch Svitoch, A.A.: Large Caspian, structure and evolution history. Pub. MSU (2014)).KeywordsContinental glaciationTransgressive seas and ocean levelAkchagylian transgressionThe evolution of salinity in the Akchagylian Sea