| Title | Estimation of maximum lake depth from the surrounding topography: towards a regional assessment of the occurrence of taliks below Arctic lakes |
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| Author | LeBlanc, A -M ;
Chartrand, J; Smith, S |
| Source | Arctic Change 2020 Conference book of abstracts/Compilation de résumés pour la Conférence Arctic; by ArcticNet; Arctic Science vol. 7, no. 1, 2021 p. 111-112, https://doi.org/10.1139/as-2021-0001  Open Access |
| Image |  |
| Year | 2021 |
| Alt Series | Natural Resources Canada, Contribution Series 20200670 |
| Publisher | Canadian Science Publishing |
| Meeting | Arctic Change 2020 Conference; December 7-10, 2020 |
| Document | book |
| Lang. | English |
| Media | paper; on-line; digital |
| Related | This publication is related to Estimation of maximum lake
depth from the surrounding topography: towards a regional assessment of the occurrence of taliks below Arctic lakes |
| File format | pdf |
| Province | Nunavut |
| NTS | 46D; 46E; 46F; 46L; 46M; 46N; 55; 56; 65A; 65B; 65G; 65H; 65I; 65J; 65O; 65P; 66A; 66B; 66G; 66H; 66I; 66J; 66O; 66P |
| Area | Rankin Inlet; Baker Lake; Kitikmeot |
| Lat/Long WENS | -100.0000 -85.0000 68.0000 60.0000 |
| Subjects | surficial geology/geomorphology; environmental geology; hydrogeology; Nature and Environment; Science and Technology; Economics and Industry; permafrost; talik; surface waters; lakes; lake water depths;
groundwater; groundwater flow; mining; mine development; transport mechanisms; mine waste products; waste disposal sites; models; ArcticDEM; Climate change; Mining industry; Digital elevation data; cumulative effects |
| Program | Climate Change
Geoscience Permafrost |
| Released | 2021 03 15 |
| Abstract | In continuous permafrost regions, taliks (areas of unfrozen ground), are mainly found beneath large and deep lakes (>2 m depth) that do not freeze to their bottom. Open taliks connected to regional
groundwater can affect the development of mine projects due to these potential pathways for contaminant transport. It is therefore important to determine which lakes are potentially underlain by open taliks, especially where lakes are used for mine
waste disposal. As a first-order estimate, the potential for talik occurrence can be assessed based on the maximum lake depth of large lakes. For regional studies, maximum lake depth may be estimated with topographic variables from the surrounding
landscape. This approach assumes that common geological processes form the landscape and the lakes, such as glacial processes. This study explores, for the first time, the use of a high-resolution elevation model (ArcticDEM) to extract topographical
variables surrounding lakes in Nunavut to run predictive models of maximum lake depth. Lakes in the area of Rankin Inlet with known maximum lake depth (n = 102) are used to assess maximum depth for all 17 145 lakes in a 5000 km2 area near the
community. We use stepwise regression to explore the topographical variables and Pearson's partial correlation coefficient to understand the relationship of a given variable to maximum lake depth. Among the eight variables considered within a buffer
relative to lake size, lake area, median slope, maximum elevation, and mean elevation were the only significant explanatory variables (p < 0.05). For the simplest and best model (least variables), lake area and median slope explained 79% of the
variance in maximum lake depth. Known maximum depth of lakes near Baker Lake and in the Kitikmeot region (n = 173) were utilized to further validate the initial model and to identify any local to regional model differences. |
| Summary | (Plain Language Summary, not published)
Open taliks, areas of unfrozen ground, are mainly found beneath large and deep lakes that do not freeze to their bottom. Their connection to the regional
groundwater can affect the development of mine projects due to these potential pathways for contaminant transport. This study explores the use of a high-resolution digital elevation model to extract topographical variables surrounding some lakes in
Nunavut to run regional models of maximum lake depth. This step is use subsequently in the assessment of the occurrence of taliks below Arctic lakes in the Kivalliq and Kitikmeot regions of Nunavut. This regional-scale characterization method could
be used by industry during environmental impact assessments. |
| GEOSCAN ID | 327953 |
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