DATE2019-01-08 12:44:22
AUTHORSAndrey Tchepalyga (1)
  1. Institute of Geography, Russian Academy of Science, Moscow, Russia
ABSTRACTThree stages of sea-level rise in the Black Sea after the LGM are recorded: from -100m to -40m in the isolated New Euxinean basin (18-10 ka BP), from -40m to the modern levels in the early Holocene (10-6 ka BP) following the reconnection with the Mediterranean Sea and the stage of Late Holocene variations between 0 and -10 - 15m. The reconstructions of the sea level oscillations are based on the data from several locations including the coastal sand barriers in the Kuban river delta and on the antique culture beds VI C BP – VI C AD in Phanagorea and other Greek sites. The first penetration of Mediterranean waters occurred during the Burgazian transgression 9.5-7.9 ka BP, when the sea level raised up to -10 -20 m. The subsequent regressive phase is represented in the Kuban river delta by the peat aged 7380 ± 80 yrs. The level of this Prekalamitian regression was about -27 m below present. During the following Kalamitian regression the sea level reached its modern value. The next Djemetian transgression with three high stands at 3.8,3.1 (up to +0.5-+1m above present value) and 2.6 ka BP was characterized by the maximum sea level and salinity. However, the above mentioned transgressions were interrupted by the short-term Kundukian (about 4.2-4 ka BP) and Fanagorean (2.5-2.3 ka BP or V-IV с. ВС) regressions when the sea level is suggested to be as low as -10 to -15 m relative to modern values. The level drop caused an emergence of the upper Black Sea shelf, Kerch strait and a major part of the Azov Sea which is well represented in peat beds, over-deepened river valleys on the Caucasian coast, and in archeological relics including flooded ancient Greek towns of Agra, Korocondama and others. The Nymphaean transgression at 2.3-1.2 ka BP (Roman time, III с. ВС - VIII с. AD) also consisted of three high-stand stages alternated with two low stands (-1 to -3m). During the Korsun regression (Vlll-X c. AD), recognized in the Khersones cultural layers the sea level likely reached -3.5- -4 m. Only minor oscillations occurred after the last Orda High stand (XIII-XV c. AD, i.e. 800-600 yrs BP). In conditions of shallow basins and plain topography the sea level oscillations resulted in substantial displacement of the shoreline and changes in coastal relief which has affected the environmental conditions of ancient people and caused changes in their diet, displaced habitats, submerged cultural beds and settlements, and caused the replacement of marine ports by river harbors.