Natural Resources CanadaGovernment of Canada
Satellite image of CanadaGeological Survey of CanadaGeological Survey of Canada
Urban Geology of the National Capital Area
Standardization and validation

The database structure is designed to contain general information on each record (Identification, Location, Surface elevation, Bedrock depth) and stratigraphic data (Generic name of soil unit, Name of material, Adjective, Modifier, Depth, Thickness). The name, Adjective and Modifier correspond to the original description provided by the source document, but the Generic name of soil horizons was derived from the original description, based on the texture of the materials. The use of a generic name eliminates the use of local terminology and provides a standard method of reporting stratigraphic units, which in return, permits the integration of borehole information and the production of regional geological models. A full description of standardization procedures for material descriptions is reported in the Oak Ridges Moraine Project. The original description is preserved in the database as it can provide further information on the nature of the materials and permit a better interpretation of the borehole logs.

Standardization and importing of the Water well records from both Ontario and Québec was relatively straightforward as the data was already in digital format. The process consisted of standardizing the units of location and measuremen,t and then selecting the fields to be imported into the Urban Geology Database. Engineering borehole logs had to be compiled from maps and paper reports. Extensive validation of the data followed the importation into the Urban Geology Database. Validation included elimination of unreliable stratigraphic descriptions (e.g. layers of overburden under layers of bedrock, missing depth, etc.) and unreliable borehole locations (conflict between geographic locations and counties or townships, wrong surface elevation or bedrock depth, etc.). All Water well records not reaching bedrock were also eliminated as the density and distribution of holes reaching bedrock provided an adequate regional coverage. Approximately 80% of the original boreholes are included into the Urban Geology Database.

2006-06-20
http://www.gsc.nrcan.gc.ca/urbgeo/natcap/sub_validation_e.php