¹⁰Be meltwater signal in Orca basin sediments, Gulf of Mexico

Abstract

An increase in the cosmogenic beryllium-10 content of the Orca basin sediments due to the flooding of the Gulf of Mexico (GM) by meltwaters during the late Wisconsin interglacial is reported. A strong negative correlation (γ=−0.99) between δ¹⁸O (in the range of −1.5‰ to +0.5‰) and ¹⁰Be/Al ratio is seen. During intense flooding reflected by a decrease in δ¹⁸O by ~2‰, this correlation may not hold as some of the sediments with low ¹⁰Be/Al ratio and deposited on the shelf and slope regions of the GM during the earlier glacial period would also be washed into the basin. The deposited sediment would then be a mixture with a ¹⁰Be/Al ratio lower than expected from the correlation.