Retreat of the Western Cordilleran Ice Sheet Margin During the Last Deglaciation
Autor: | Brent M. Goehring, Marc W. Caffee, Olav B. Lian, Brian Menounos, Christopher M. Darvill |
---|---|
Rok vydání: | 2018 |
Předmět: |
010506 paleontology
geography geography.geographical_feature_category 010504 meteorology & atmospheric sciences 01 natural sciences Paleontology Geophysics 13. Climate action Margin (machine learning) Deglaciation General Earth and Planetary Sciences Ice sheet human activities Geology 0105 earth and related environmental sciences |
Zdroj: | Darvill, C M, Menounos, B, Goehring, B M, Lian, O B & Caffee, M W 2018, ' Retreat of the western Cordilleran Ice Sheet margin during the last deglaciation ', Geophysical Research Letters, vol. 45, no. 18, pp. 9710-9720 . https://doi.org/10.1029/2018GL079419 |
ISSN: | 1944-8007 0094-8276 |
Popis: | The timing of Cordilleran Ice Sheet deglaciation along the central coast of British Columbia, Canada, informs climate forcing and early human migration. Thirty‐two 10Be exposure ages from glacial erratics and local bedrock on the western margin of the former ice sheet represent the earliest exposure ages for the Cordilleran Ice Sheet during the last deglaciation. These data show the western ice margin was retreating by 18.1 ± 0.2 ka, consistent with the global record of ice mass loss. In contrast, parts of the southern margin reached a maximum at ca. 17.6‐16.6 ka, and our data demonstrate a diachronous response of the Cordilleran Ice Sheet during deglaciation. We also show that a low altitude site was exposed by at least 17.7 ± 0.3 ka, implying that numerous ice‐free areas existed along the coastal margin by this time, providing a viable route for the first humans entering the Americas. |
Databáze: | OpenAIRE |
Externí odkaz: |