Evaluating the historical sedimentation patterns in two different Mediterranean deep environments (Sardinia and Sicily channels)

Abstract

The sediment accumulation rate in the Sardinia and Sicily channels in the central part of the Mediterranean Sea was studied by using natural and fallout radionuclides, 210Pb and 137Cs, respectively, in two deep sediment cores. Different sedimentation regimes were identified, indicating substantial differences in accumulation rates and historical patterns. The 210Pb-derived mean accumulation rate found in the Strait of Sardinia was 0.05 g. cm-2. y-1, lower than that in Sicily Channel (0.1 g. cm-2. y-1) suggesting an inverse correlation with water depth. Excess 210Pb inventories were 24 ± 1 and 6.0 ± 0.4 kBq. m-2, while the fluxes to the sediment were 745 ± 31 and 188 ± 11 Bq. m-2. y-1 in Sicily and Sardinia channels, respectively. The use of 137Cs failed to validate the established chronologies, while its inventories were 450 Bq. m-2 and 355 Bq. m-2 in the Sicily and Sardinia channel, respectively.