GEOSCAN Search Results: Fastlink


TitleA semi-automated esker detection method (EDM) for improved quantification of glaciated landscapes
AuthorBroscoe, D; Cummings, D I; Russell, H A J; Sharpe, D R
SourceGeological Survey of Canada, Technical Note no. 2, 2011, 21 pages,
PublisherNatural Resources Canada
Mediaon-line; digital
File formatpdf (Adobe Acrobat Reader)
ProvinceOntario; Northwest Territories
NTS55K; 55N; 75O/05
AreaArtillery Lake; Hudson Bay
Lat/Long WENS-94.0000 -92.0000 64.0000 62.0000
Lat/Long WENS-107.5000 -107.5000 63.5000 63.2500
Subjectssurficial geology/geomorphology; glacial deposits; glacial landforms; eskers; landscape types; digital elevation models
Illustrationslocation maps; cross-sections; plots; aerial photographs; histograms
ProgramGEM Tri-Territorial Information management & Databases (Remote Predictive Mapping / Mineral Resource Assessment), GEM: Geo-mapping for Energy and Minerals
Released2011 07 14
AbstractA methodology is presented for the quantification of eskers that uses Canadian digital elevation data (CDED) and legacy esker line-work from Geological Survey of Canada publications. Using ESRI® ArcGIS® and an esker detection module (EDM) coded in Python, the CDED data are smoothed using user-defined filter windows. A difference surface is produced that emphasizes ridge areas and is used to create polygons. The legacy esker line-work is used as a training data set to extract ridge areas within a user-defined buffer. The EDM results have been tested against the input training data and a local data set generated manually from aerial photographic interpretation. Depending upon terrain characteristics, the success of the data extraction ranges from 65 to 81 per cent against the esker line-work and 35 to 72 per cent against the more geographically limited aerial photographic interpretation. The variable success reflects esker size related to both relief and width in the CDED data.