GEOSCAN Search Results: Fastlink


TitleLithalsa distribution, morphology and landscape associations in the Great Slave Lowlands, Northwest Territories
LicencePlease note the adoption of the Open Government Licence - Canada supersedes any previous licences.
AuthorStevens, C W; Wolfe, S AORCID logo; Gaanderse, A J R
SourceGeological Survey of Canada, Open File 7255, 2012, 41 pages, Open Access logo Open Access
PublisherNatural Resources Canada
Documentopen file
Maps1 map
Map Info.geological, lithalsa distribution, 1:166,666
Mediaon-line; digital
RelatedThis publication is related to Distributions of degraded and intact lithalsas, North Slave region, Northwest Territories
File formatreadme
File formatpdf; shp; rtf
ProvinceNorthwest Territories
NTS85J/10; 85J/11; 85J/12; 85J/13; 85J/14; 85J/15
Lat/Long WENS-116.0833 -114.4167 62.8833 62.3333
Subjectsengineering geology; surficial geology/geomorphology; Nature and Environment; permafrost; ground ice; freezing ground; glaciation; glacial deposits; vegetation; remote sensing; Great Slave Lowlands; LiDAR; Quaternary; Cenozoic
Illustrationslocation maps; aerial photographs; tables; photographs; graphs
ProgramClimate Change Geoscience
Released2012 12 05
AbstractThe distribution of ice-rich terrain is an important geotechnical consideration for the engineering of northern infrastructure. Lithalsas represent one form of ice-rich terrain that can be identified on the basis of surface geomorphology and cryostratigraphy. A total of 1,777 ice-rich lithalsas were mapped over 3,680 km2 using monochromatic stereo-pair airphotos, across the Great Slave Lowlands and Uplands, NWT, Canada. Boreholes indicate lithalsas in this region consist of ice-rich silt and clay, with segregated ice lenses up to 10 cm thick. Three distinct morphologies are recognized from LiDAR bare-earth DEMs including; (i) circular, (ii) linear and (iii) crescentic plan-view shapes, which exhibit hill-like or ridge-like forms up to 8 m in height and more than 100 m in width. The linear relationship between lithalsa height and width indicates that 1 cm of vertical growth may be accompanied by 15 cm of lateral growth at the peripheral edges. Lithalsa distribution is skewed towards lower elevations, with 97.7% located within the Great Slave Lowlands. These features predominately occur adjacent to water bodies and follow the regional distribution of frost susceptible glaciolacustrine silt and clay. Landscape associations suggest lithalsa formation is controlled by sedimentological, thermal and hydrological conditions. This Open File reports the first account of lithalsas within this region.

Date modified: