This tabular dataset provides the locations of sites where the presence or absence of near-surface permafrost was ascertained in the plains and shield regions of Alberta. The dataset is restricted to northern Alberta, because in Alberta, with the exception of the Alberta Rocky Mountains and Foothills region, no permafrost exists south of 56° N latitude. The data represent point locations where the presence or absence of permafrost was established using soil probes, augers, hand-dug soil pits or using shallow coring equipment. In addition, the permafrost site locations are augmented by mapping of permafrost-related landforms and features using 1 m resolution airborne Light Detection and Ranging (LiDAR) digital elevation model (DEM) data and high-resolution satellite data (SPOT 6) and orthoimagery.
The dataset includes information from field observations collected by the Alberta Geological Survey (AGS), and data collected by the Geological Survey of Canada (GSC) through the collaborative GSC/AGS Shallow Gas and Diamonds and the Targeted Geoscience Initative-2 projects. These data are compiled along with information from published reports, environmental impact assessments, journal publications and university theses.
1. The permafrost site location inventory was produced by compiling information relating to permafrost occurrences from field observations collected by the Alberta Geological Survey, and data collected by the Geological Survey of Canada through the collaborative GSC/AGS Shallow Gas and Diamonds and the Targeted Geoscience Initative-2 projects. These observations are compiled along with information derived from published reports, environmental impact assessments, journal publications, and university theses.
The data represent point locations where the presence or absence of permafrost had been established using soil probes, augers, hand-dug soil pits or using shallow coring equipment. Other field observation, such as those from sites that utilized geological sections and borrow pits were excluded because it is possible that permafrost could have occurred in these locations, but was not observable within the depth of the exposure.
The permafrost site location inventory also includes a small number of locations where permafrost had been mapped as polygon features. In these cases, a single random point location was selected within the polygon boundary.
2. The permafrost site location inventory was augmented by new mapping of permafrost-related landforms and features using 1 m resolution airborne LiDAR DEM data and high-resolution SPOT 6 satellite imagery and orthoimagery.
To ensure that mapping occurred systematically and was evenly distributed, 4000 sample tiles of 1 km2 were randomly generated across the model area. Excluding water features, 3996 sample tiles were used for the new mapping. Each sample tile was manually inspected for the presence or absence of permafrost using the previously described remote sensing datasets. The criteria used in this interpretation consisted of: a) peat plateaus and bogs containing palsas, usually showing collapse scars, were assumed to contain permafrost; b) veneer bogs containing collapse scars and being drained by runnels were also assumed to contain permafrost in the locations that are adjacent to the collapse scars; c) other bogs that either contain, or do not contain internal lawns, as well as other wetland and non-wetland land cover types, were assumed not to contain permafrost.
Within each sample tile, a stratified sample consisting of a single point per wetland type (permafrost, bog, fen, swamp, non-wetland, excluding open water) was manually collected. These points represent the "Mapped wetland types in sample tiles" features in the "Source" attribute of the tabular dataset. For sample tiles that did not contain permafrost features upon initial examination, a stratified random sample following the above scheme was collected based on a wetland map derived from the Alberta Ground Cover Classification Mosaic (Alberta Agriculture and Forestry, 2013). These points represent the "Stratified random points in sample tiles" features in the "Source" attribute of the tabular dataset.