GEOSCAN Search Results: Fastlink

GEOSCAN Menu


TitleThe Great Slave Lowland: the legacy of Glacial Lake McConnell
AuthorWolfe, S A; Morse, P D; Kokelj, S V; Gaanderse, A J
SourceLandscapes and landforms of western Canada; by Slaymaker, O (ed.); World Geomorphological Landscapes 2016 p. 87-96, https://doi.org/10.1007/978-3-319-44595-3 5
Year2016
Alt SeriesEarth Sciences Sector, Contribution Series 20140375
PublisherSpringer International Publishing
Documentserial
Lang.English
Mediapaper; on-line; digital
File formatpdf (Adobe® Reader®)
ProvinceNorthwest Territories
NTS85I/03; 85I/04; 85I/05; 85I/06; 85I/11; 85I/12; 85I/13; 85I/14; 85J; 85K/01; 85K/02; 85K/03; 85K/06; 85K/07; 85K/08; 85K/09; 85K/10; 85K/11; 85K/14; 85K/15; 85K/16; 85N/01; 85N/02; 85N/03; 85N/06; 85N/07; 85N/08; 85N/09; 85N/10; 85N/11; 85O/01; 85O/02; 85O/03; 85O/04; 85O/05; 85O/06; 85O/11; 85O/12; 85P/03; 85P/04
AreaGreat Slave Lake; Yellowknife; Dettah; Behchoko; Edzo
Lat/Long WENS-117.5000 -113.0000 63.7500 62.0000
Subjectssurficial geology/geomorphology; environmental geology; Nature and Environment; glacial history; glaciation; deglaciation; glacial lakes; water levels; emergence; permafrost; ground ice; ice lenses; periglacial features; vegetation; organic deposits; peatlands; soils; clays; silts; climate; temperature; subsidence; slumps; thermal analyses; thermal regimes; Great Slave Lowland; Taiga Shield Ecozone; Glacial Lake McConnell; Ancestral Great Slave Lake; Canadian Shield; Laurentide Ice Sheet; glaciolacustrine sediments; lacustrine nearshore sediments; discontinuous permafrost; lithalsas; ice segregation; forests; permafrost degradation; terrain sensitivity; geological hazards; limit of submergence, glaciolacustrine; permafrost thickness; climate change; landscape disturbance; aggradation; active layer; Phanerozoic; Cenozoic; Quaternary
Illustrationslocation maps; geoscientific sketch maps; photographs; profiles; schematic representations
ProgramLand-based Infrastructure, Climate Change Geoscience
Released2016 12 02
AbstractThe Great Slave Lowland of the Taiga Shield is an 11,000 km2 low-elevation granitic bedrock plain along the north shore of Great Slave Lake, Northwest Territories. It is characterized by a mosaic of coniferous and deciduous forest cover, wetlands, sparsely vegetated bedrock outcrops, and peatlands. The region was glaciated until about 13,000 years ago and then inundated by Glacial Lake McConnell and by ancestral Great Slave Lake, which gradually declined towards the present lake elevation. Consequently, fine-grained glacilacustrine and nearshore lacustrine sediments are broadly distributed across the region. Permafrost is widespread within forest-covered sediments and peatlands, but is not sustained beneath bedrock outcrops, leading to an extensive, but discontinuous, permafrost distribution. Lithalsas, which are permafrost mounds up to 8 m in height and several hundred metres in length, are also abundant. These form by ice segregation within mineral soil, as permafrost aggrades into the fine-grained sediments following lake level recession. Lithalsas are most common within the first few tens of metres above the present level of Great Slave Lake, indicating that many are late Holocene in age and some <1000 years. These elevated surfaces favour the establishment of deciduous forests with thin organic ground cover and with mean annual ground temperatures typically between -0.5 and -1.5 °C. With annual mean air temperatures consistently warming since the 1940s, this terrain is vulnerable to thawing and subsidence, with impacts on the ecology, hydrology, and population of the region.
GEOSCAN ID295681