Compositional trends through the Holocene mud succession of the southwestern Black Sea shelf: Implications for sedimentary provenance and water-level history

摘要: Abstract Cores MAR02-45 and MAR05-03 were raised from 68–69 m water depth on the SW Black Sea shelf indicate transgression submergence beneath several tens of metres before 11.0 cal ka. Those who postulate a lowstand below − 100 m until approximately 9.1 cal ka reconnection with world ocean have suggested that sites like must been located in perched lakes what is now modern shelf. However, silt- clay-fraction mineralogy samples provides no evidence for shift provenance at 9.1 cal ka, earlier input local rivers later broader region. Sedimentary abundances Sc, Fe, Co, Ce, La, Th Y also show significant downcore trends. These elements likely reside aluminosilicate mineral grains shed terrestrial sources, so negligible variation suggests long-term continuity composition detrital supply. More critically, volume pre-9.1 cal ka sediment around > 25 times expected yield over 5000 year period, other more substantial sources are required. The predominant silt size recovered sediments, configuration late Holocene currents western Sea, analogies dispersal systems elsewhere suggest bulk fine-grained muds these came Danube Kamchiya drainage basins where thick deposits unconsolidated Pleistocene loess strongly dissected. To reach core shelf, this material advected deltas by unobstructed marine currents. Only thin event beds (tempestites) fine sand lower part cores interpreted to source Strandja Mountains Thrace. Comparison palynology surface Delta its associated coastal lagoons sediments confirms hypothesis deposition ancient lake untenable.