This GIS dataset is part of a digital compilation of the bedrock geology of NTS areas 72E, 72L, 73D, and 73E. It is one of the datasets used to produce Alberta Geological Survey (AGS) Maps 567, 568, 569, and 570. This dataset represents the compilation of existing geological maps and original geological mapping by AGS staff. Mapping included field observations and creating three-dimensional models of subsurface stratigraphy based on the interpretation of geophysical logs from oil and gas wells. Each three-dimensional formation surface was projected to a model of the bedrock surface, and the intersection formed the first approximation of the position of the geological contact at the base of the surficial deposits. We adjusted these preliminary contacts to honour outcrop data and the interpretation of the bedrock unit immediately below surficial deposits in individual wells. The data were created in file geodatabase format and output for public distribution in shapefile format. AGS Open File Reports 2010-10 and 2011-13 present additional information on data sources related to this dataset.

The dataset includes subsurface stratigraphic picks for the interfingering members that define the transition between the Belly River Group and the Lea Park Formation in east-central Alberta (Townships 1 to 62, Ranges 1W4 to 21W4) made from wireline geophysical well logs. Coarsening upwards, siltstone to sandstone-dominated members of the Belly River Group include (from youngest to oldest) the upper Birch Lake, lower Birch Lake, Ribstone Creek, Victoria, and Brosseau members. Interfingering mudstone-dominated members of the Lea Park Formation include the Mulga, Grizzly Bear, Vanesti, and Shandro members. Where the top and base are present, we calculated isochore values for each member. Well data were screened to detect errors resulting from deviated wells, as well as incorrect ground and kelly bushing elevation data. We used statistical methods to identify local and regional statistical outliers, which were examined individually.

This GIS dataset is part of a digital compilation of the bedrock geology of NTS areas 72E, 72L, 73D, and 73E. It is one of the datasets used to produce Alberta Geological Survey (AGS) Maps 567, 568, 569, and 570. This dataset represents the compilation of existing geological maps and original geological mapping by AGS staff. Mapping included field observations and creating three-dimensional models of subsurface stratigraphy based on the interpretation of geophysical logs from oil and gas wells. Each three-dimensional formation surface was projected to a model of the bedrock surface, and the intersection formed the first approximation of the position of the geological contact at the base of the surficial deposits. We adjusted these preliminary contacts to honour outcrop data and the interpretation of the bedrock unit immediately below surficial deposits in individual wells. The data were created in file geodatabase format and output for public distribution in shapefile format. AGS Open File Reports 2010-10 and 2011-13 present additional information on data sources related to this dataset.