Advance, deglacial and sea-level chronology for Foxe Peninsula, Baffin Island, Nunavut

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• 作者：Daniel J. Utting ; John C. Gosse ; Samuel E. Kelley ; Kayla J. Vickers ; Brent C. Ward and Michelle S. Trommelen
• 刊名：Boreas
• 出版年：2016
• 出版时间：July 2016
• 年：2016
• 卷：45
• 期：3
• 页码：439-454
• 全文大小：5015K
• ISSN：1502-3885

文摘

The impact of the Laurentide Ice Sheet (LIS) deglaciation on Northern Hemisphere early Holocene climate can be evaluated only once a detailed chronology of ice history and sea-level change is established. Foxe Peninsula is ideally situated on the northern boundary of Hudson Strait, and preserves a chronostratigraphy that provides important glaciological insights regarding changes in ice-sheet position and relative sea level before and after the 8.2 ka cooling event. We utilized a combination of radiocarbon ages, adjusted with a new locally derived ΔR, and terrestrial in-situ cosmogenic nuclide (TCN) exposure ages to develop a chronology for early-Holocene events in the northern Hudson Strait. A marine limit at 192 m a.s.l., dated at 8.1–7.9 cal. ka BP, provides the timing of deglaciation following the 8.2 ka event, confirming that ice persisted at least north of Hudson Bay until then. A moraine complex and esker morphosequence, the Foxe Moraine, relates to glaciomarine outwash deltas and beaches at 160 m a.s.l., and is tightly dated at 7.6 cal. ka BP with a combination of shell dates and exposure ages on boulders. The final rapid collapse of Foxe Peninsula ice occurred by 7.1–6.9 cal. ka BP (radiocarbon dates and TCN depth profile age on an outwash delta), which supports the hypothesis that LIS melting contributed to the contemporaneous global sea-level rise known as the Catastrophic Rise Event 3 (CRE-3).