|Résumé||(disponible en anglais seulement)|
The objective of the Tri-Territorial Surficial Database Project is to provide an accessible regional-scale surficial knowledge base to support northern
exploration and economic development. This is accomplished through a digital compilation and queriable surficial database of new and existing surficial geology maps of Northwest Territories, Nunavut, and Yukon. The Project coordinates with ongoing
Geo-mapping for Energy and Minerals (GEM) field mapping activities on Victoria Island, Wager Bay, Cumberland Peninsula, as well as other GEM and Climate Change Remote Predictive Mapping (RPM) initiatives in the Yellowknife area, Hall Peninsula, and
MacKay Lake (NTS 75M).
The surficial database of 704 maps, representing 629 publications, includes 241 maps (in 152 publications) from the Northwest Territories (currently 106 maps in digital format), 303 maps from Nunavut (currently 211 in
digital format), and 160 maps in digital format from the Yukon, compiled by the Yukon Geological Survey. Within the Northwest Territories, about 52% by area is covered by reconnaissance maps at 1M scale with little or no field work, and therefore
lacks sufficient surficial geology knowledge. Approximately 48% is covered by maps of adequate surficial knowledge. To date, 230 of the NWT legacy map legends have been captured in digital format in Excel tables.
A new Geological Survey of Canada
(GSC) surficial geology legend has recently been developed to ensure the implementation of standard map units and symbols, and thus facilitate new Quaternary geology mapping and correlation of map units across all Territories and Canada. Conversion
of legacy map units to the new legend is ongoing and will provide significant queriable advantages to the database.
The following summarizes the various stages in preparing legacy maps to digital format: base maps and imagery require assembly;
imagery is georeferenced to base map; quality control done to ensure georeferencing accuracy; abnormalities and interpretation issues are resolved either by data manager or geologist; final map geodatabase is quality checked for accurate contacts,
attribution, direction and sense of features; final digital products are translated and converted into a standardized geodatabase. Legend translations provide the mechanism for mapping legacy map units to the new geodatabase. Tools, using ESRI
toolboxes and Python scripting, are being developed to automate the conversion process and streamline the translation of legacy data complying with the Geological Map Flow (GMF) standards. Conversion is ongoing and digital legacy data are in various
formats, including Shapefiles, CAD, non-standardized Geodatabases, Microstation, Coverages, and other legacy Arc formats.
An interactive web-based portal is being developed from which both the GEM Tri-Territorial Surficial and Bedrock databases
will eventually be accessed, providing an effective communication tool for the exploration industry, land-use planners and policy-makers.