| Title | Paraglacial and paraperiglacial landform-sediment assemblages of the Grays Bay Road corridor region, NU, and implications for climate-resilient infrastructure |
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| Author | Morse, P ; Smith,
S; Parker, R |
| 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. 117-118, https://doi.org/10.1139/as-2021-0001  Open Access |
| Image |  |
| Year | 2021 |
| Alt Series | Natural Resources Canada, Contribution Series 20200654 |
| Publisher | Canadian Science Publishing |
| Meeting | Arctic Change 2020 Conference; December 7-10, 2020 |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| Related | This publication is related to Periglacial landforms of the
Grays Bay Road corridor region, Nunavut, and implications for climate-resilient infrastructure |
| File format | pdf |
| Province | Nunavut |
| NTS | 76M/14 |
| Area | Grays Bay |
| Lat/Long WENS | -111.5000 -111.0000 68.0000 67.7500 |
| Subjects | surficial geology/geomorphology; environmental geology; Nature and Environment; Science and Technology; Health and Safety; engineering geology; permafrost; ground ice; massive ice; periglacial features;
ice-wedge polygons; landforms; sediments; climate effects; sediment stability; ground temperatures; subsidence; sediment transport; drainage; models; creep; Canadian Shield; Slave Province; Climate change; Northern Canada; permafrost thaw;
Infrastructures; glaciofluvial sediments |
| Program | Climate Change
Geoscience Permafrost |
| Released | 2021 03 15 |
| Abstract | Knowledge of permafrost conditions is required to develop climate-resilient northern infrastructure and to identify potential geohazards. Where present, permafrost constitutes a landscape foundation.
Its stability and integrity are controlled by ground temperatures, surficial and bedrock materials, and ice contents, which are, in turn, a function of landscape history. The effects of permafrost thaw include decreased load bearing capacity, ground
surface settlement, and increased transport of sediment and water (melted ice). In rapidly changing northern climates, these adjustments to thaw can be major geohazards for northern infrastructure, but with differential effects due to the often
heterogeneous distribution of surficial materials. Development of climate-resilient northern infrastructure can benefit from a holistic land system approach that attempts to understand how a landscape was formed by investigating the collection of
landforms and sediments within it. Our research considers paraglacial and paraperiglacial landform-sediment assemblages (not landforms or sediments in isolation) that constitute the landscape of northern Slave Geological Province and attempts to link
them to the processes that formed them. The ultimate goal is to enable inferences on past and future landscape evolution supported by process-form models established from contemporary examples, in a region where very little is known about permafrost
conditions. Here we present newly mapped landform-sediment assemblages and patterns in their spatial distribution for 72% of the 1600 km2 area that is within 5 km of the proposed Grays Bay Road corridor. In combination with sparse sedimentological
and cryostratigraphic records, we develop a set of preliminary landform-sediment assemblages. One notable landform-sediment assemblage is glaciofluvial deposits over massive ice, dissected by ice-wedge polygons. Exhibiting long-term creep, this
assemblage likely has the highest potential for thermal adjustment, and it represents a substantial potential geohazard in this region that needs to be considered in planning climate-resilient infrastructure. |
| Summary | (Plain Language Summary, not published)
Permafrost conditions can be hazardous to northern infrastructure if the ground thaws, which can happen due to climate change or developing
infrastructure on permafrost. Here we present a holistic approach to better understand the distribution of permafrost terrain landforms, and their relations to sediments and ground ice, in the northern Slave Geological Province where very little is
known about permafrost conditions. Notably, we identify a landform-sediment assemblage of sands and gravels (of glacial origin) likely deposited over very icy permafrost, upon which ice-wedge polygons have also developed. This assemblage has a
highest potential for terrain instability if it thaws, and represents a substantial potential geohazard in this region that needs to be considered in planning development. |
| GEOSCAN ID | 327926 |
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