| Title | Oriented-lake development in the context of late Quaternary landscape evolution, McKinley Bay Coastal Plain, western Arctic Canada |
| |
| Author | Wolfe, S ; Murton,
J; Bateman, M; Barlow, J |
| Source | Quaternary Science Reviews vol. 242, 106414, 2020 p. 1-22, https://doi.org/10.1016/j.quascirev.2020.106414  Open Access |
| Year | 2020 |
| Alt Series | Natural Resources Canada, Contribution Series 20190136 |
| Publisher | Elsevier Ltd. |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf; html |
| Province | Northwest Territories |
| Area | McKinley Bay; Canada |
| Lat/Long WENS | -133.2483 -129.2028 70.2964 69.4919 |
| Subjects | Science and Technology; paleogeography; permafrost; radiocarbon dating; Holocene; morphology; eolian deposits; fluvial deposits; radiocarbon dates; radiocarbon dating; Pleistocene; Arctic North America;
Laurentide Ice Sheet; Geomorphology; Quaternary |
| Illustrations | location maps; graphs; tables; diagrams |
| Program | Climate Change
Geoscience Permafrost |
| Released | 2020 08 15 |
| Abstract | Oriented lakes - characterized by elongate forms, central basins and shallow littoral shelves - are common features of circum-arctic coastal lowlands. The environmental conditions, geological processes
and chronology associated with the development of oriented lakes, however, are little known but essential for understanding how such Arctic lowlands evolve. Using combined techniques of field and drill-log stratigraphy and sedimentology, luminescence
and radiocarbon dating methods and geomorphic mapping, we reconstruct the landscape evolution leading toward oriented-lake formation on the McKinley Bay Coastal Plain of western Arctic, Canada - a region with over 900 oriented lakes. Most lakes with
deep central basins are inherited from a preglacial braidplain (ca. 73-27 ka) and alluvial braided-channel network that extended beyond the glacial limit (ca. 18.6-14.3 ka). Eolian erosion, active during the lateglacial and postglacial period (ca.
12.8-1.9 ka), reworked fluvial deposits. Eolian processes modified existing basins and created other shallow deflationary basins, as small barchanoid dunes migrated under cold, dry paraglacial conditions between about 12.8 and 10.7 ka. Vegetation
cover developed at the onset of the early Holocene climatic optimum ca. 10.7 ka, and parabolic dunes were active between 9.6 and 4.6 ka. Thus, oriented lakes developed in basins conditioned by fluvial and eolian processes. 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. 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 | 326899 |
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