00000nam 2200000za 4500 9.819817 CaOODSP 20251031142446 cr ||||||||||| 160621s2014 onc|||||o f|0| 0 eng d CaOODSP eng n-cn--- M183-2/7720E-PDF Morse, Peter Douglass, 1975- Icings in the Great Slave region (1985-2014), Northwest Territories, mapped from Landsat Imagery [electronic resource] / [by] P.D. Morse and S.A. Wolfe. Ottawa : Natural Resources Canada, 2014. 38 p. : figures, graphs, photos. Open file (Geological Survey of Canada) ; 7720 Includes bibliographic references. Icings are sheet-like masses of layered ice that form over the winter by freezing of successive flows of water on the ground surface or on top of river or lake ice. Because icings can negatively impact the performance of seasonal and all-season roads, they are a transportation risk in the Arctic. Therefore, maps of their occurrence and reoccurrence provide important geoscience information required for development and transportation infrastructure planning. In this study, threshold values of band ratios were used to derive a set of icing maps from Landsat image time series of images (1985 - 2014), located within the Slave Geological Province (WRS-2 Path 47/Row 16). The icings maps were generated using image data acquired in late-spring when the region is largely snow-free, but ice bodies remain. A water mask created from summer image data was used to differentiate frozen water bodies so any remaining ice was considered to be land-fast, and thus icings formed from winter overland flow of water. Icing occurrence and reoccurrence maps were generated by overlaying the successive icing distribution maps in a Geographic Information System. This Open File contains digital, georeferenced icing data. gccst Ice gccst Geophysics gccst Geology gccst Geomorphology Wolfe, Stephen Andrew, 1963- Canada. Natural Resources Canada. Geological Survey of Canada. Open file (Geological Survey of Canada) 7720 (CaOODSP)9.506878 PDF 2.75 MB https://publications.gc.ca/collections/collection_2016/rncan-nrcan/M183-2-7720-eng.pdf