A Periglacial Landsystem Analysis in the Canadian High Arctic: A Tool for Planetary Geomorphology
Permafrost underlies 50% of Canada’s terrain and underlies 24% of the Earth’s total land area. It is a major driving force in the generation and evolution of patterned ground landforms such as polygons, stone circles, mud boils, and stripes, etc. that are seen on both the surface of the Earth and Ma...
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| Format: | Text |
| Language: | English |
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Scholarship@Western
2020
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| Online Access: | https://ir.lib.uwo.ca/etd/7528 https://ir.lib.uwo.ca/context/etd/article/9916/viewcontent/20201221_A_Periglacial_Landsystem_Analysis_in_the_Canadian_High_Arctic___A_Tool_for_Planetary_Geomorphology.pdf |
| Summary: | Permafrost underlies 50% of Canada’s terrain and underlies 24% of the Earth’s total land area. It is a major driving force in the generation and evolution of patterned ground landforms such as polygons, stone circles, mud boils, and stripes, etc. that are seen on both the surface of the Earth and Mars, specifically in periglacial domains. The distribution of subsurface ice in these landforms (i.e. polygonal terrain) on Earth is a key constraint on past climate and process-form relationships in high arctic and periglacial regions. These landforms also have the potential of storing ice in the subsurface meaning that the volumetric concentration of buried ice can provide information about the processes that led to its deposition. In this research, two Canadian High Arctic study sites were analyzed: Strand Fiord, Axel Heiberg Island (ᐅᒥᖕᒪᑦ ᓄᓈᑦ, Umingmat Nunaat) and Haughton River Valley, Devon Island (ᑕᓪᓗᕈᑎᑦ, Tallurutit). Methods in this research involved the utilization of (1) ground penetrating radar (GPR) for 3D ice-wedge volume estimation, (2) Light Detection and Ranging (LiDAR) for hyper-resolution digital elevation model (DEM) generation and quantifying the degree of spatial sorting in patterned ground using Kernel Density Estimation (KDE), (3) sedimentology for grain size and facies association in order to infer depositional environment, (4) fieldwork notes and measurement, and (5) drone and aerial photos for 3D photogrammetry models. In Strand Fiord, ice-wedge geometry and volume were calculated to be asymmetric and 43.28 m3 respectively in a 25 m x 25 m grid within the study area; ice-wedge polygons were associated with areas of active transition (i.e. secondary/tertiary polygons that have experienced multiple episodes of cracking). In the Haughton River Valley, patterned ground spatial distribution and sorting were related to the local periglacial region such as microtopography, slope and lithology wherein fine (clay, sand) sediments were often associated with the formation of frost-shattered nets, ... |
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