The map identifies surficial materials and associated landforms left by the retreat of the last glaciers and non glacial environments. The surficial geology is based on compilation of existing maps. This work provides new geological knowledge and improves our understanding ofthe distribution, nature and glacial history of surficial materials. It contributes to resource assessments and effective land use management. This new surficial geology map product represents the conversion of the map "Surficial Materials of Canada" (Fulton, 1995) and its legend, using the Geological Survey of Canada's Surficial Data Model (SDM version 2.0) which can be found in Open File 7631 (Deblonde et al.,2014). All geoscience knowledge and information from map 1880A that conformed to the current SDM were maintained during the conversion process. However, only terrestrial units are depicted on this map. Map units below modern sea level or major lake levels are not shown but are maintained in the digital data of this publication. Where additional information was required in certain regions of the Arctic and Cordillera, legacy geology map data were used. These maps are listed in the digital "Map Information" document. All other source maps used in map 1880A are not relisted here. The purpose of converting legacy map data to a common science language and common legend is to enable and facilitate the efficient digital compilation, interpretation, management and dissemination of geologic map information in a structured and consistent manner. This provides an effective knowledge management tool designed around a geo-database which can expand following the type of information to appear on new surficial geology maps.

This entry provides access to surficial geology maps that have been published by the Geological survey of Canada. Two series of maps are available: "A Series" maps, published from 1909 to 2010 and "Canadian Geoscience Maps", published since 2010. Three types of CGM-series maps are available: 1)Surficial Geology: based on expert-knowledge full air photo interpretation (may include interpretive satellite imagery, Digital Elevation Models (DEM)), incorporating field data and ground truthing resulting from extensive, systematic fieldwork across the entire map area. Air photo interpretation includes map unit/deposit genesis, texture, thickness, structure, morphology, depositional or erosional environment, ice flow or meltwater direction, age/cross-cutting relationships, landscape evolution and associated geological features, complemented by additional overlay modifiers, points and linear features, selected from over 275 different geological elements in the Surficial Data Model. Wherever possible, legacy data is also added to the map. 2)Reconnaissance Surficial Geology: based on expert-knowledge full air photo interpretation (may include interpretive satellite imagery, DEMs), with limited or no fieldwork. Air photo interpretation includes map unit/deposit genesis, texture, thickness, structure, morphology, depositional or erosional environment, ice flow or meltwater direction, age/cross-cutting relationships, landscape evolution and associated geological features, complemented by additional overlay modifiers, points and linear features, selected from over 275 different geological elements in the Surficial Data Model. Wherever possible, legacy data is also added to the map. 3)Predictive Surficial Geology: derived from one or more methods of remote predictive mapping (RPM) using different satellite imagery, spectral characteristics of vegetation and surface moisture, machine processing, algorithms etc., DEMs, where raster data are converted to vector, with some expert-knowledge air photo interpretation (training areas or post-verification areas), varying degrees of non-systematic fieldwork, and the addition of any legacy data available. Each map is based on a version of the Geological Survey of Canada's Surficial Data Model (https://doi.org/10.4095/315021), thus providing an easily accessible national surficial geological framework and context in a standardized format to all users. "A series" maps were introduced in 1909 and replaced by CGM maps in 2010. The symbols and vocabulary used on those maps was not as standardized as they are in the CGM maps. Some "A series" maps were converted into, or redone, as CGM maps, Both versions are available whenever that is the case. In addition to CGM and "A series" maps, some surficial geology maps are published in the Open File series. Those maps are not displayed in this entry, but can be found and accessed using the NRCan publications website, GEOSCAN:(https://geoscan.nrcan.gc.ca).

To support improved groundwater geoscience knowledge for southern Ontario, a regional 3-D model of the surficial geology of southern Ontario has been developed as a part of a collaboration between the Ontario Geological Survey and the Geological Survey of Canada. Covering approximately 66,870 km2 in area, the model is a synthesis of existing geological models, surficial geology mapping, and subsurface data. The model is a simplified 9-layer reclassification of numerous mapped local surficial sediment formations in places over 200 m thick with a total volume of approximately 2,455 km3. The model integrates 1:50,000 scale surficial geology mapping with 90 m bathymetrically corrected topographic digital elevation model (DEM) and 8 existing local 3-D models. Archival subsurface data include 10,237 geotechnical and stratigraphic boreholes, 3,312 picks from geophysical surveys, 15,902 field mapping sites and sections, 537 monitoring and water supply wells and 282,995 water well records. Roughly corresponding to regional aquifer and aquitard layers, primary model layers are (from oldest to youngest): Bedrock, Basal Aquifer, Lower Sediment, Regional Till, Post Regional Till Channel Fill, Glaciofluvial Sediment, Post Regional Till Mud, Glaciolacustrine Sand and Recent Sediment / Organics. Modelling was completed using an implicit modelling application (LeapFrog®) complemented by an expert knowledge approach to data classification and rules-based Expert System procedure for data interpretation and validation. An iterative cycle of automated data coding, intermediate model construction and manual data corrections, expert evaluations, and revisions lead to the final 3-D model. A semi-quantitative confidence assessment has been made for each model layer surface based on data quality, distribution and density. This surficial geology model completes the development of a series of regional 3-D geological and hydrogeological models for southern Ontario.