| Title | Late Quaternary landscape evolution and origin of the oriented-lakes coastal plain, Tuktoyaktuk Peninsula, western Arctic Canada |
| Author | Wolfe, S A; Murton, J B; Bateman, M D; Barlow, J |
| Source | Geological Society of America, Abstracts With Programs vol. 51, no. 5, 332210, 2019 p. 1, https://doi.org/10.1130/abs/2019AM-332210 (Open
Access) |
| Links | Online - En ligne
|
| Year | 2019 |
| Alt Series | Natural Resources Canada, Contribution Series 20190333 |
| Publisher | Geological Society of America |
| Meeting | Geological Society of America Annual Meeting; Phoenix, AZ; US; September 22-26, 2019 |
| Document | serial |
| Lang. | English |
| Media | on-line; digital |
| File format | html; pdf |
| Province | Northwest Territories |
| NTS | 107B/01; 107B/02; 107B/03; 107B/06; 107B/07; 107B/08; 107B/09; 107B/10; 107B/11; 107B/14; 107B/15; 107C/01; 107C/02; 107C/03; 107C/07; 107C/08; 107C/09; 107C/10; 107C/16; 107D/11; 107D/12; 107D/13; 107D/14;
107D/15; 107E/02; 107E/03; 107E/04 |
| Area | Tuktoyaktuk Peninsula |
| Lat/Long WENS | -135.0000 -129.0000 70.2500 68.0000 |
| Subjects | surficial geology/geomorphology; Nature and Environment; surface waters; lakes; geological history; basin evolution; fluvial processes; alluvial plains; glacial history; glaciation; Wisconsinian glacial
stage; braided channels; sediment reworking; permafrost; ground ice; periglacial features; talik; currents; McKinley Bay Coastal Plain; Toker Point Stade; climate change; landscape evolution; coastal plains; oriented lakes; eolian processes; eolian
sediments; wave action; Phanerozoic; Cenozoic; Quaternary |
| Program | Climate Change
Geoscience, Permafrost |
| Released | 2019 09 01 |
| Abstract | Environmental conditions, geological processes and chronology associated with the initiation and development of oriented lakes over millennial timescales are little known but essential for understanding
how these arctic lowlands evolve. We report field observations from the McKinley Bay Coastal Plain of western Arctic, Canada, to elucidate such landscape evolution. The region includes over 900 oriented lakes, most with deep central basins and
shallow marginal shelves. Landscape evolution is reconstructed from preglacial to postglacial conditions, with oriented lakes developing in basins conditioned by fluvial and eolian processes. Initially, the region was occupied by a preglacial
braidplain (ca. 73-27 ka) and, during late Wisconsinan glaciation, by an alluvial braided-channel network that extended beyond the glacial limit (ca. 18.6-14.3 ka). Most lakes with deep central basins are inherited from this fluvial channel network.
Eolian processes were active during the late glacial and postglacial period (ca. 12.8-1.9 ka), reworking fluvial deposits except where glacial outwash mantled the surface north of the Toker Point Stade limit. Eolian erosion modified existing basins
and created other shallow deflationary basins, as small barchanoid dunes migrated downwind under cold, dry paraglacial conditions between about 12.8 and 10.7 ka. At the onset of the Early Holocene climatic optimum, vegetation cover developed ca. 10.7
ka and parabolic dunes formed and continued to migrate between 9.6 and 4.6 ka. In the absence of much near-surface ground ice, lateral expansion of deep-basin lakes and shallow stabilized deflationary basins predominated during the Late Holocene
through wind-induced wave and current processes. Lake deepening has progressed as taliks penetrate the underlying permafrost. Overall, this sequence of oriented-lake formation does not support a thaw lake cycle but, rather, small basin evolution of a
periglacial landscape. |
| Summary | (Plain Language Summary, not published)
The environmental conditions associated with oriented lake initiation and development are not well known. We report on a region in western Arctic with
over 900 oriented lakes. The oriented lakes developed in basins conditioned by fluvial and eolian processes. Most lakes are inherited from a fluvial channel network. Eolian processes later reworked fluvial deposits. Eolian erosion modified existing
basins and created other shallow deflationary basins, as small barchan dunes migrated downwind under cold, dry paraglacial conditions. Vegetation cover later developed and parabolic dunes formed and continued to migrate. In the absence of much
near-surface ground ice, lateral expansion of deep-basin lakes and shallow stabilized deflationary basins predominated during the Late Holocene through wind-induced wave and current processes. Lake deepening progressed as taliks penetrate the
underlying permafrost. Overall, this sequence of oriented-lake formation does not support a thaw lake cycle but, rather, small basin evolution of a periglacial landscape. |
| GEOSCAN ID | 321393 |
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