| Title | Late glacial retreat of the Lancaster Sound Ice Stream and early Holocene onset of Arctic/Atlantic throughflow in the Arctic Island channels |
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| Author | Kelleher, R; Jennings, A; Andrews, J; Marchitto, T; Feng, S; Woelders, L; Jenner, K; Normandeau, A ; Bennett, R; Brookins, S; Brooks, N K S |
| Source | Arctic, Antarctic and Alpine Research vol. 54, no. 1, 2022 p. 395-427, https://doi.org/10.1080/15230430.2022.2110689  Open Access |
| Image |  |
| Year | 2022 |
| Alt Series | Natural Resources Canada, Contribution Series 20210623 |
| Publisher | Taylor & Francis |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf; html |
| Province | Nunavut; Northwest Territories; Yukon |
| NTS | 560; 340; 120; 99; 89; 79; 69; 59; 49; 39; 29; 19; 98; 88; 78; 68; 58; 48; 38; 28; 117; 107; 97; 87; 77; 67; 57; 47; 37; 27; 116; 106; 96; 86; 76; 66; 56; 46; 36; 26; 115; 105; 95; 85; 75; 65; 55; 45; 35;
25; 15; 16 |
| Area | 29; 19; Baffin Bay; Lancaster Sound |
| Lat/Long WENS | -174.0000 -27.0000 85.0000 58.0000 |
| Subjects | Science and Technology; Nature and Environment; deglaciation; Parry Channel; Quaternary |
| Illustrations | location maps; tables; graphs; charts; photographs; cross-plots |
| Program | Public Safety Geoscience
Baffin Bay |
| Released | 2022 09 26 |
| Abstract | Multiple proxies in three sediment cores from Northwestern Baffin Bay document the timing of Lancaster Sound Ice Stream (LSIS) retreat that led to Arctic-Atlantic throughflow in Parry Channel, an
important source of freshwater that can impact the Atlantic Meridional Overturning Circulation. The Late Glacial to Holocene timing of ice retreat and channel opening and the responses of the regional ocean environment to these events are presented.
We use quantitative mineral composition, foraminiferal assemblages, biogenic silica, ice-rafted debris (IRD), and 14C-based age models to document and date the events and environmental changes occurring during deglaciation of this major marine
channel. Findings show that retreat of the LSIS into Lancaster Sound occurred before ~15.3 cal ka BP, about 800 years before the onset of major iceberg calving events from the LSIS, named the Baffin Bay Detrital Carbonate events (BBDC 1 and BBDC 0).
The end of BBDC 0 occurred at ~10.6 cal ka BP, which coincides with the opening of Parry Channel. A marine environment productive of calcareous benthic and planktic foraminifera, with diminished meltwater, seasonal sea ice, warmer summer
temperatures, and inflowing, nutrient-rich Arctic surface water characterizes the interval between the opening of Parry Channel and the opening of Nares Strait. Paired planktic and benthic 14C ages over this 2,200-year interval show diminishing age
offsets suggesting progressive mixing of the upper ~850-900 m of the water column. The opening of Nares Strait by ~8.2 cal ka BP coincides with increased biogenic silica in the form of abundant, large centric diatoms and dissolution of CaCO3. The
paucity of calcareous organisms after 8.2 cal ka BP resulted in poor chronological control in the cores to interpret changing environments after 8.2 cal ka BP. |
| Summary | (Plain Language Summary, not published)
This paper provides revised timing of retreat of the Landcaster Sound Ice Stream and of the opening of Parry Channel |
| GEOSCAN ID | 329574 |
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