Hudson Strait Quaternary sediments and late glacial and deglaciation history: a discussion and summary

Abstract

Thick, multisequence deposits of ice-contact sediments in the deep floors of Eastern and Western basins and on the seaward side of the sill at the entrance to Hudson Strait attest to the magnitude of glacial ice streams in Hudson Strait. Some of these are thought to have extended to the shelf edge and to be a source of Heinrich events in the Labrador Sea and North Atlantic Ocean. Later south-to-north ice advances across Eastern basin onto southeastern Baffin Island were less far-reaching seaward. The sediment record in the floor of Eastern basin and on its northern and northwestern flanks show that the basin was occupied by a grounded and progressively thinning ice sheet during the time of the Noble Inlet advance recognized on southeastern Baffin Island. Chronological data and similarities in the marine-terrestrial ice-sheet behaviour patterns suggest that this was one and the same ice sheet. Three potential sources for this advance are examined: Baffin Island, a Hudson Strait ice stream, and Quebec

Heinrich 0 on the east Canadian margin: Source, distribution, and timing

“…It is relatively well dated to a maximum calibrated age of ~11.3 cal kyr B.P. (with absolute minimal reservoir age offset Δ R = 0) [ Kaufman et al ., ; MacLean et al ., ; Pearce , ], which is too young when compared to the AI07‐14G DC layer. The unlikelihood of the link with the Gold Cove advance is also confirmed by the carbonate stratigraphy of Cartwright Saddle [ Jennings et al ., ], in which the Gold Cove and H0 are clearly different events represented by separate DC peaks.…”

Comment on “Catastrophic ice shelf breakup as the source of Heinrich event icebergs” by C. L. Hulbe et al.

“…We have presented one model in which a cooling event could trigger a surge and an outburst flood from beneath an ice stream such as that in Hudson Strait [ Alley et al , 2005], and we expect that several other models are possible. Large incised channels are suggested on seismic profiles from the Hudson Strait seafloor and adjacent shelf [ Andrews and MacLean , 2003; MacLean et al , 2001] and may relate to these postulated outburst floods.…”

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

“…ka BP appears only in an earlier paper by the same author (Rashid et al, 2011). Other literature consistently refers to the GC at an earlier age up to thousand years earlier (Miller and Kaufman, 1990;Kaufman et al, 1993;Veillette et al, 1999;MacLean et al, 2001;Manley and Miller, 2001;Dyke, 2004;Briner et al, 2009;Roy et al, 2009;Cofaigh et al, 2010;Lewis et al, 2012).…”