Signature of the Gold Cove event (10.2 ka) in the Labrador Sea

Abstract

One of the least known catastrophic meltwater and sediment-release events of the Laurentide ice-sheet during the early Holocene is the so-called Gold Cove proglacial lake outbursts, a drainage event through the Hudson Strait. This event may have disturbed circulation in the Labrador Sea by releasing freshwater. Here, we report data from four sediment cores and re-analysis of six published records spatially covering >2000 km from the mouth of Hudson Strait to the northeastern Sohm Abyssal Plain. Abundant detrital carbonate (DC) and less positive δ18O values in Neogloboquadrina pachyderma (sinistral) suggest a short-lived meltwater event in the Hudson Strait region. This discharge transported detrital-carbonate-rich sediment and shallow-water benthic forams southward along the Labrador margin, mixing with the North Atlantic Current near the Grand Banks. Sediments associated with this event were guided through the deep Labrador Sea from the mouth of Hudson Strait and the Northwest Atlantic Mid-Ocean Channel (NAMOC) to the Sohm Abyssal Plain. Furthermore, we report less positive δ13C values in the epibenthic foram Cibicidoides wuellerstorfi from the southern Labrador Sea during this event. Our twenty one 14C-AMS dates in addition to earlier published radiocarbon dates from the Labrador margin suggest that this DC event was coeval with the Gold Cove proglacial lake outbursts related to re-advance of the Laurentide ice-sheet.