Pleistocene and Holocene Climate Reconstruction at Two Moose Lake, Central Yukon, Using Stable Isotopes and 14C-DOC Radiocarbon from Ice wedges, Pore Ice and Buried Sediments
The objective of this thesis was to reconstruct the Sedimentary, Cryostratigraphic and Paleoclimatic history of Two Moose Lake, central Yukon using a new analytical technique for dating ice wedges using Dissolved Organic Carbon (DOC). During two field seasons in August 2013 and April 2014, 442 sampl...
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Université d'Ottawa / University of Ottawa
2017
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ftdatacite:10.20381/ruor-20145 2023-05-15T17:10:30+02:00 Pleistocene and Holocene Climate Reconstruction at Two Moose Lake, Central Yukon, Using Stable Isotopes and 14C-DOC Radiocarbon from Ice wedges, Pore Ice and Buried Sediments Grinter, Michael 2017 https://dx.doi.org/10.20381/ruor-20145 http://www.ruor.uottawa.ca/handle/10393/35862 en eng Université d'Ottawa / University of Ottawa Ice Wedges Paleoclimate Stable Isotopes Yukon Radiocarbon AMS Buried Ice Glaciation DOC Quaternary Holocene Pleistocene Text Thesis article-journal ScholarlyArticle 2017 ftdatacite https://doi.org/10.20381/ruor-20145 2021-11-05T12:55:41Z The objective of this thesis was to reconstruct the Sedimentary, Cryostratigraphic and Paleoclimatic history of Two Moose Lake, central Yukon using a new analytical technique for dating ice wedges using Dissolved Organic Carbon (DOC). During two field seasons in August 2013 and April 2014, 442 samples were collected from a newly exposed headwall of a thaw slump with 7 ice wedges and over 4m of sediment. Using cryostratigraphy, granulometry, stable isotopes and 18 14C-DOC ages, 4 stratigraphic units were delineated: 1) a sediment-rich ice layer inferred to be of glacial origin (>32ka BP); 2) a silt-rich layer deposited during the Holocene Thermal Maximum (~10 to 8.2ka BP); 3) a silt with organics layer deposited from ~8ka to 6.4ka BP, and 4) a paleo-active layer and modern active layer. 14C-DOC dating indicated two periods of ice wedge activity at Two Moose Lake, the first during the late Pleistocene (31,608 to 12,990 yr cal BP) and from the mid-Holocene to present (6,328 to 892 yr cal BP). The presence of late-Pleistocene aged ice wedges at Two Moose Lake supports the common belief of an unglaciated central Yukon during the most recent McConnell glaciation from 29.6 to 13ka BP. Values for δ18O from the Holocene- and Pleistocene-aged ice wedges were 2-3‰ and 5-9‰ depleted compared those of modern precipitation from Mayo (-22.32‰). Medium-resolution (2-4cm) sampling along with multiple 14C-DOC samples along a transect allowed for the creation of a continuous δ18O and temperature age profile to be developed from multiple ice wedges, showing a strong consistency between overlapping ages. The reconstruction of the paleoclimate of Two Moose lake is consistent with known events from southern Yukon including the Boutellier Inderstadial, a cold unglaciated central Yukon during the McConnell Glaciation, warming during the Holocene Thermal Maximum (HTM) followed by an extreme cooling event at 8.2ka BP, a cooling event at 4.2ka BP, and the subsequent warming to present temperatures. Thesis Mayo Yukon DataCite Metadata Store (German National Library of Science and Technology) Two Moose Lake ENVELOPE(-138.365,-138.365,64.735,64.735) Yukon |
institution |
Open Polar |
collection |
DataCite Metadata Store (German National Library of Science and Technology) |
op_collection_id |
ftdatacite |
language |
English |
topic |
Ice Wedges Paleoclimate Stable Isotopes Yukon Radiocarbon AMS Buried Ice Glaciation DOC Quaternary Holocene Pleistocene |
spellingShingle |
Ice Wedges Paleoclimate Stable Isotopes Yukon Radiocarbon AMS Buried Ice Glaciation DOC Quaternary Holocene Pleistocene Grinter, Michael Pleistocene and Holocene Climate Reconstruction at Two Moose Lake, Central Yukon, Using Stable Isotopes and 14C-DOC Radiocarbon from Ice wedges, Pore Ice and Buried Sediments |
topic_facet |
Ice Wedges Paleoclimate Stable Isotopes Yukon Radiocarbon AMS Buried Ice Glaciation DOC Quaternary Holocene Pleistocene |
description |
The objective of this thesis was to reconstruct the Sedimentary, Cryostratigraphic and Paleoclimatic history of Two Moose Lake, central Yukon using a new analytical technique for dating ice wedges using Dissolved Organic Carbon (DOC). During two field seasons in August 2013 and April 2014, 442 samples were collected from a newly exposed headwall of a thaw slump with 7 ice wedges and over 4m of sediment. Using cryostratigraphy, granulometry, stable isotopes and 18 14C-DOC ages, 4 stratigraphic units were delineated: 1) a sediment-rich ice layer inferred to be of glacial origin (>32ka BP); 2) a silt-rich layer deposited during the Holocene Thermal Maximum (~10 to 8.2ka BP); 3) a silt with organics layer deposited from ~8ka to 6.4ka BP, and 4) a paleo-active layer and modern active layer. 14C-DOC dating indicated two periods of ice wedge activity at Two Moose Lake, the first during the late Pleistocene (31,608 to 12,990 yr cal BP) and from the mid-Holocene to present (6,328 to 892 yr cal BP). The presence of late-Pleistocene aged ice wedges at Two Moose Lake supports the common belief of an unglaciated central Yukon during the most recent McConnell glaciation from 29.6 to 13ka BP. Values for δ18O from the Holocene- and Pleistocene-aged ice wedges were 2-3‰ and 5-9‰ depleted compared those of modern precipitation from Mayo (-22.32‰). Medium-resolution (2-4cm) sampling along with multiple 14C-DOC samples along a transect allowed for the creation of a continuous δ18O and temperature age profile to be developed from multiple ice wedges, showing a strong consistency between overlapping ages. The reconstruction of the paleoclimate of Two Moose lake is consistent with known events from southern Yukon including the Boutellier Inderstadial, a cold unglaciated central Yukon during the McConnell Glaciation, warming during the Holocene Thermal Maximum (HTM) followed by an extreme cooling event at 8.2ka BP, a cooling event at 4.2ka BP, and the subsequent warming to present temperatures. |
format |
Thesis |
author |
Grinter, Michael |
author_facet |
Grinter, Michael |
author_sort |
Grinter, Michael |
title |
Pleistocene and Holocene Climate Reconstruction at Two Moose Lake, Central Yukon, Using Stable Isotopes and 14C-DOC Radiocarbon from Ice wedges, Pore Ice and Buried Sediments |
title_short |
Pleistocene and Holocene Climate Reconstruction at Two Moose Lake, Central Yukon, Using Stable Isotopes and 14C-DOC Radiocarbon from Ice wedges, Pore Ice and Buried Sediments |
title_full |
Pleistocene and Holocene Climate Reconstruction at Two Moose Lake, Central Yukon, Using Stable Isotopes and 14C-DOC Radiocarbon from Ice wedges, Pore Ice and Buried Sediments |
title_fullStr |
Pleistocene and Holocene Climate Reconstruction at Two Moose Lake, Central Yukon, Using Stable Isotopes and 14C-DOC Radiocarbon from Ice wedges, Pore Ice and Buried Sediments |
title_full_unstemmed |
Pleistocene and Holocene Climate Reconstruction at Two Moose Lake, Central Yukon, Using Stable Isotopes and 14C-DOC Radiocarbon from Ice wedges, Pore Ice and Buried Sediments |
title_sort |
pleistocene and holocene climate reconstruction at two moose lake, central yukon, using stable isotopes and 14c-doc radiocarbon from ice wedges, pore ice and buried sediments |
publisher |
Université d'Ottawa / University of Ottawa |
publishDate |
2017 |
url |
https://dx.doi.org/10.20381/ruor-20145 http://www.ruor.uottawa.ca/handle/10393/35862 |
long_lat |
ENVELOPE(-138.365,-138.365,64.735,64.735) |
geographic |
Two Moose Lake Yukon |
geographic_facet |
Two Moose Lake Yukon |
genre |
Mayo Yukon |
genre_facet |
Mayo Yukon |
op_doi |
https://doi.org/10.20381/ruor-20145 |
_version_ |
1766067088811622400 |