ABSTRACT: 2.5D surficial geology mapping: Digital cartography incorporating the best source data available.

CGRG Bibliography of Canadian Geomorphology
Search Results

Author :

Date :

Title :

Publication :

Issue :

Page(s) :

Abstract

Since 1995, the Geological Survey of Canada–Québec (GSC-Québec) has been developing a new map production technique. As part of an effort to transfer the technology, GSC-Québec has presented this new digital cartographic process in-house as well as at national and international meetings (Canada and USA) since 2000. This 2.5D mapping technique is based on an 11 steps procedure. From conventional air-photo interpretation to scanning, orientation, orthorectification, merging, digitizing, legend compilation and editing, to final map composition including logos, scale, location map, etc, this technique, currently used at GSC-Québec, is presently being implemented in other GSC offices. Our challenge in the production of "The next geology map of Canada" is to be innovative in using our well developed in-house mapping techniques with actual best worldwide practices. A new series of 2.5D geomorphological and surficial deposit maps could integrate marine surficial maps based on high resolution regional bathymetric surveys (Gulf of St-Lawrence and along the east coast), including LIDAR surveys where available. This would certainly enhance the final product. These new geomorphological and surficial geology maps would be seen by most Canadians has the minimal requirement in this computerized world. Draping the maps on the best Digital Elevation Model (DEM) available for Canada would produce a high quality 2.5D product that geologists and others could use to better understand the complex relationships between our landscape and the underlying geology. From standard geological use, like helping identifying important ice flow changes as shown by drumlins fields, to effective outreach documents for the public, these new 2.5D maps would enable a better definition of some important geomorphological aspects of major regional constituents of Canada, from the highest reliefs in the west, north and east to the lowest elevations below sea level where such maps exist. GSC-Québec is also working on a new generalization technique based on length, width and surface algorithms including retraction smoothing of different contour types and polygon generalization by iteration. This technique will have to be improved within the next few years through new projects, if we want to incorporate detailed information (new Bathymetry/LIDAR data) and still produce a seamless map of Canada. This "New geomorphological and surficial geology map of Canada" would provide an integrated view of our knowledge of terrestrial and underwater environments. It would become the most flexible, digital (with navigation and query functionalities), fully web-based outreach and science oriented product.

Bibliography of Canadian Geomorphology