Grants / RFBR 02-05-64428

Project completed.
RFBR # 02-05-64428

Extreme Late Quaternary marine transgressions and their relation to megafloods in river basins in the Ponto-Caspian region


Final report

Conception of Late Glacial Extremal Floods was elaborate on the new base. Flood water source in the river valleys (superfloods) and on the watershed was recovered. Influence of the Flood events on the archaeological cultures was found.

Chronology and dynamics of Khvalynean transgression, as a Great Flood epicenter was reconstructed. Age is from 17 to 10 ka. Duration is 5-6 ka. 10 oscillations with 500-600 years duration. 3-member structure of Khvalynean proposed: Lower, Middle and Upper Khvalynean with Elton and Enotaevka regressions in between.

Manych-Kerch Late Glacial spillway reconstruction was provided. His length was 900 km. There are 13 morphological segments along the strait and 3 transversal geomorphologic different age structures. The oldest accumulative forms with level +50 +35 m asl. corresponds to maximal level of Khvalynean transgression and the biggest water discharge up to 50000 m3/sec. Lower level +20 +25 corresponds to Talginka oscillation and last one level +13 +15 m correspond to Bujnaksk oscillation. It was provided environmental reconstruction of ancient Manych strait (16-14ca) as outflow of Early hvalyniant basin: sea level - +50m, width - up to 10km, depth 20-30m, water speed - 0,2-0,3m/sec, salinity - 10%0, and water discharge - 40-60000m3/sec. It is 200 time less then evaluation of V. Baker.

It was found parametres of ancient Chogray bay of Earlyhvalynean marine basin of ancient Caspian: sea level - up to +50m a.s.l., depth - more 25m, salinity - more 10‰ as well as reach special content of mollusk faune (more 10 species). It was recovered transgressive-regressive cicles in Holocene sea level changes: 1,5-2,0 ca cycle with rate 15-25m and 300-400 years cicle with rate 3-4m. Evidences of these oscillations was found in culter leyers of antic site Fanagoria. Megafloods evidences during 16-10ca was found in Seim, Don and Kalaus river valleys.

Paleohydrological reconstruction of inner Eurasian basins, united by Cascade of the marine and lake basins was provided: Aral Sea Ц Uzboy - Early Khvalynean basins Ц Manych-Kerch spillway - Bosphorus spillway - Sea of Marmara Ц Dardanelle's up to Aegean Sea. Next parameters were calculated: sea level, water space, flooding space, water volume, salinity and water exchange volume. Tracer's method was used for indication of these basins. Ponto-Caspian basins Cascade was the biggest in the world and reached of space 1,5 mln km2.

W. Ryan and W. Pitman hypothesis of Black Sea Noah's Flood was critically revised and new alternative model of Great Flood proposed.

Field study of megafloods in river valleys Don, Kalaus, West Manych; ancient marine sand barriers and marine terraces of the Black and Azov seas, marine shelf of Anapa-Gelendzik region as well as study of archaeological sites Fanagoria, Avdeevo, Byki, Kamennaya Balka.