Cenozoic Stratigraphy of Northwestern Alberta (parts of NTS 83M-O and 84B-G)

This report presents a revised Cenozoic geological framework and depositional history of northwestern Alberta based on previous geological investigations and re-examination of previously collected data. It outlines the methodology of 1) facies analysis to characterize six stratigraphic units and 2) data collation and analysis to correlate stratigraphic units on a regional scale. Relogging of cored boreholes allowed reinterpretation and confirmation of previously delineated stratigraphic units. Stratigraphic correlations of Cenozoic units were made on cross-sections using lithology data from water-well records, previously recorded data from outcrop and boreholes, and re-examined core. These stratigraphic correlations were used to construct a regional Cenozoic stratigraphic framework in the Peace River area, which was subsequently used to inform modelling of the Cenozoic geological column that overlies the Peace River bedrock model previously completed by the Alberta Geological Survey.

The Cenozoic stratigraphy of northwestern Alberta has been previously characterized for the purpose of landslide analysis, aggregate resources, natural gas migration, kimberlite indicator mineral assessment, and understanding the glacial history of the area. However, the lateral extent of Cenozoic stratigraphic units that host significant aquifers, aggregate resources, semi-impermeable units, and hydrocarbon reservoirs, and their interconnectivity, are poorly understood. Delineation of the geometry and interconnectivity of fine- and coarse-grained Cenozoic stratigraphic units is important for predicting potential contaminant migration pathways, estimating the volume of coarse-grained units for groundwater and aggregate investigations, and evaluating the reservoir architecture in places of natural gas accumulations.