The timing of the Gold Cove glacial event: A comment on “Signature of the Gold Cove event (10.2 ka) in the Labrador Sea”

Abstract

The recent paper in Quaternary International, Rashid et al. (2014) “Signature of the Gold Cove event (10.2 ka) in the Labrador Sea” attributes sediment layers rich in detrital carbonate (DC) in several marine sediment cores in the Labrador Sea to the so-called Gold Cove (GC) glacial advance of the early Holocene. The age estimate for the GC event as well as the correlations between sediment cores in this study are based on radiocarbon dates, mostly from previously published studies. Although this work provides a good overview of an apparently widespread DC layer in the early Holocene, the reported age of 10.2 cal. ka BP for the actual Gold Cove event is too young, due to a mistake made during re-calibration of the original radiocarbon dates used to describe the event. The 14C dates have been corrected to compensate for the marine reservoir effect two times, leading to an unrealistically large total reservoir age of more than thousand years. By applying such a large marine reservoir offset, the final calibrated age becomes too young. Originally the GC event was described to consist of an advance and retreat phase, in total spanning several centuries. The Gold Cove event should therefore more accurately be reported as an age range, and it occurred most likely ca. 500 years earlier than 10.2 ka BP, the age reported by Rashid et al. (2014).