Cartographic Intactness and the Three Miles to One Inch Sectional Maps of Western Canada

Larry Laliberté, GIS Librarian, University of Alberta

Brian Harley wrote that the blank spaces on a map are sometimes as beckoning as their densest line work. Echoing his statement, this presentation will look at the process of georeferencing and performing raster to vector conversions of the 3-miles to 1-inch sectional maps of Western Canada, to extract measures of line work density. These density measures or “Cartographic Intactness” could serve as a useful spatial metric when aggregated up to the Western Township grid for establishing thresholds of the early 20th Century human foot print on the West, and delineating areas undisturbed by the cartographer’s pen.