Identification of last interglacial deposits in eastern Beringia: a cautionary note from the Palisades, interior Alaska
Last interglacial sediments in unglaciated Alaska and Yukon (eastern Beringia) are commonly identified by palaeoecological indicators and stratigraphic position ~2-5m above the regionally prominent Old Crow tephra (124±10ka). We demonstrate that this approach can yield erroneous age assignments usin...
Published in: | Journal of Quaternary Science |
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Format: | Article in Journal/Newspaper |
Language: | English |
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2011
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Online Access: | https://pure.qub.ac.uk/en/publications/identification-of-last-interglacial-deposits-in-eastern-beringia-a-cautionary-note-from-the-palisades-interior-alaska(814b0e73-881d-4d96-8a2a-b1744d7c1c7d).html https://doi.org/10.1002/jqs.1464 http://www.scopus.com/inward/record.url?partnerID=yv4JPVwI&eid=2-s2.0-79954458963&md5=5f3622a60513a584b7b42d03eb966822 |
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ftqueensubelpubl:oai:pure.qub.ac.uk/portal:publications/814b0e73-881d-4d96-8a2a-b1744d7c1c7d 2023-05-15T17:52:45+02:00 Identification of last interglacial deposits in eastern Beringia: a cautionary note from the Palisades, interior Alaska Reyes, A.V. Zazula, G.D. Kuzmina, S. Ager, T.A. Froese, D.G. 2011-03-01 https://pure.qub.ac.uk/en/publications/identification-of-last-interglacial-deposits-in-eastern-beringia-a-cautionary-note-from-the-palisades-interior-alaska(814b0e73-881d-4d96-8a2a-b1744d7c1c7d).html https://doi.org/10.1002/jqs.1464 http://www.scopus.com/inward/record.url?partnerID=yv4JPVwI&eid=2-s2.0-79954458963&md5=5f3622a60513a584b7b42d03eb966822 eng eng info:eu-repo/semantics/restrictedAccess Reyes , A V , Zazula , G D , Kuzmina , S , Ager , T A & Froese , D G 2011 , ' Identification of last interglacial deposits in eastern Beringia: a cautionary note from the Palisades, interior Alaska ' , Journal of Quaternary Science , vol. 26 , no. 3 , pp. 345-352 . https://doi.org/10.1002/jqs.1464 /dk/atira/pure/subjectarea/asjc/1900/1901 Earth and Planetary Sciences (miscellaneous) /dk/atira/pure/subjectarea/asjc/1900/1911 Palaeontology article 2011 ftqueensubelpubl https://doi.org/10.1002/jqs.1464 2022-02-09T22:08:12Z Last interglacial sediments in unglaciated Alaska and Yukon (eastern Beringia) are commonly identified by palaeoecological indicators and stratigraphic position ~2-5m above the regionally prominent Old Crow tephra (124±10ka). We demonstrate that this approach can yield erroneous age assignments using data from a new exposure at the Palisades, a site in interior Alaska with numerous exposures of last interglacial sediments. Tephrochronology, stratigraphy, plant macrofossils, pollen and fossil insects from a prominent wood-rich organic silt unit are all consistent with a last interglacial age assignment. However, six 14C dates on plant and insect macrofossils from the organic silt range from non-finite to 4.0 14C ka BP, indicating that the organic silt instead represents a Holocene deposit with a mixed-age assemblage of organic material. In contrast, wood samples from presumed last interglacial organic-rich sediments elsewhere at the Palisades, in a similar stratigraphic position with respect to Old Crow tephra, yield non-finite 14C ages. Given that local permafrost thaw since the last interglaciation may facilitate reworking of older sediments into new stratigraphic positions, minimum constraining ages based on 14C dating or other methods should supplement age assignments for last interglacial sediments in eastern Beringia that are based on palaeoecology and stratigraphic association with Old Crow tephra. Article in Journal/Newspaper Old Crow permafrost Alaska Beringia Yukon Queen's University Belfast Research Portal Palisades ENVELOPE(159.167,159.167,-82.833,-82.833) The Palisades ENVELOPE(159.167,159.167,-82.833,-82.833) Yukon Journal of Quaternary Science 26 3 345 352 |
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Queen's University Belfast Research Portal |
op_collection_id |
ftqueensubelpubl |
language |
English |
topic |
/dk/atira/pure/subjectarea/asjc/1900/1901 Earth and Planetary Sciences (miscellaneous) /dk/atira/pure/subjectarea/asjc/1900/1911 Palaeontology |
spellingShingle |
/dk/atira/pure/subjectarea/asjc/1900/1901 Earth and Planetary Sciences (miscellaneous) /dk/atira/pure/subjectarea/asjc/1900/1911 Palaeontology Reyes, A.V. Zazula, G.D. Kuzmina, S. Ager, T.A. Froese, D.G. Identification of last interglacial deposits in eastern Beringia: a cautionary note from the Palisades, interior Alaska |
topic_facet |
/dk/atira/pure/subjectarea/asjc/1900/1901 Earth and Planetary Sciences (miscellaneous) /dk/atira/pure/subjectarea/asjc/1900/1911 Palaeontology |
description |
Last interglacial sediments in unglaciated Alaska and Yukon (eastern Beringia) are commonly identified by palaeoecological indicators and stratigraphic position ~2-5m above the regionally prominent Old Crow tephra (124±10ka). We demonstrate that this approach can yield erroneous age assignments using data from a new exposure at the Palisades, a site in interior Alaska with numerous exposures of last interglacial sediments. Tephrochronology, stratigraphy, plant macrofossils, pollen and fossil insects from a prominent wood-rich organic silt unit are all consistent with a last interglacial age assignment. However, six 14C dates on plant and insect macrofossils from the organic silt range from non-finite to 4.0 14C ka BP, indicating that the organic silt instead represents a Holocene deposit with a mixed-age assemblage of organic material. In contrast, wood samples from presumed last interglacial organic-rich sediments elsewhere at the Palisades, in a similar stratigraphic position with respect to Old Crow tephra, yield non-finite 14C ages. Given that local permafrost thaw since the last interglaciation may facilitate reworking of older sediments into new stratigraphic positions, minimum constraining ages based on 14C dating or other methods should supplement age assignments for last interglacial sediments in eastern Beringia that are based on palaeoecology and stratigraphic association with Old Crow tephra. |
format |
Article in Journal/Newspaper |
author |
Reyes, A.V. Zazula, G.D. Kuzmina, S. Ager, T.A. Froese, D.G. |
author_facet |
Reyes, A.V. Zazula, G.D. Kuzmina, S. Ager, T.A. Froese, D.G. |
author_sort |
Reyes, A.V. |
title |
Identification of last interglacial deposits in eastern Beringia: a cautionary note from the Palisades, interior Alaska |
title_short |
Identification of last interglacial deposits in eastern Beringia: a cautionary note from the Palisades, interior Alaska |
title_full |
Identification of last interglacial deposits in eastern Beringia: a cautionary note from the Palisades, interior Alaska |
title_fullStr |
Identification of last interglacial deposits in eastern Beringia: a cautionary note from the Palisades, interior Alaska |
title_full_unstemmed |
Identification of last interglacial deposits in eastern Beringia: a cautionary note from the Palisades, interior Alaska |
title_sort |
identification of last interglacial deposits in eastern beringia: a cautionary note from the palisades, interior alaska |
publishDate |
2011 |
url |
https://pure.qub.ac.uk/en/publications/identification-of-last-interglacial-deposits-in-eastern-beringia-a-cautionary-note-from-the-palisades-interior-alaska(814b0e73-881d-4d96-8a2a-b1744d7c1c7d).html https://doi.org/10.1002/jqs.1464 http://www.scopus.com/inward/record.url?partnerID=yv4JPVwI&eid=2-s2.0-79954458963&md5=5f3622a60513a584b7b42d03eb966822 |
long_lat |
ENVELOPE(159.167,159.167,-82.833,-82.833) ENVELOPE(159.167,159.167,-82.833,-82.833) |
geographic |
Palisades The Palisades Yukon |
geographic_facet |
Palisades The Palisades Yukon |
genre |
Old Crow permafrost Alaska Beringia Yukon |
genre_facet |
Old Crow permafrost Alaska Beringia Yukon |
op_source |
Reyes , A V , Zazula , G D , Kuzmina , S , Ager , T A & Froese , D G 2011 , ' Identification of last interglacial deposits in eastern Beringia: a cautionary note from the Palisades, interior Alaska ' , Journal of Quaternary Science , vol. 26 , no. 3 , pp. 345-352 . https://doi.org/10.1002/jqs.1464 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1002/jqs.1464 |
container_title |
Journal of Quaternary Science |
container_volume |
26 |
container_issue |
3 |
container_start_page |
345 |
op_container_end_page |
352 |
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1766160470674243584 |