| Summary: | Analyses of 13 sediment cores and 2800 km of 3.5 kHz seismic profiles reveal that the majority of the sediments on the Labrador continental slope was deposited by hemipelagic settling and ice-rafting (53%), debris flows (7%) and turbidity currents (34%) during the Wisconsinan Glaciation. Only minor amounts (6%) are attributed to contour current activity and related processes. Eight sedimentary facies were differentiated which include (1) hemipelagic (H); (2) hemipelagic (HI) with ice-rafted detritus (IRD); (3) debris-flow deposits (subfacies D1, D2, D3), spill-over turbidite (T), headspill turbidite (TH), turbidite (TI) alternating with IRD; and (4) contourite (C) and nepheloid-flow deposits (N). Six major glacial advances were identified in Mid- to Late-Wisconsinan (64-10 ka) slope sediments by 6 very dark hemipelagic units containing abundant sinistral-coiling, cold-water foraminifera. The associated ice-retreat phases are characterized by the occurrence of turbidites, debris-flow deposits, nepheloid-flow deposits, and ice-rafted debris (IRD).
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