Open File Report 2009-13

Open File Report 2009-13

OFR 2009-13

Sandstone-Hosted Uranium in Southern Alberta: Petrographic Descriptions of Exposed Upper Cretaceous and Tertiary Rock Formations

Author(s) Matveeva, T.M. Stepic, J.M. Date 2010-01-15

Exposed Upper Cretaceous and Tertiary rock formations in southern Alberta were sampled for petrographic study. This report describes the mineralogy, diagenesis and porosity of the Porcupine Hills, Willow Creek, St. Mary River, Whitemud, Kneehills Tuff (Battle Formation), Blood Reserve, Oldman, Foremost and Milk River formations. It presents detailed descriptions and accompanying high-quality photomicrographs to highlight the properties of the rocks and help interpret clastic rocks for evaluation of uranium potential. We then used these descriptions to make comparisons between the physical properties of southern Alberta exposed bedrock and those of the rocks containing sandstone-hosted uranium deposits in other areas of the world.

Anomalous uranium values in shale and sandstone of the St. Mary River and Willow Creek formations suggest that uranium-enrichment processes were active in these formations. Grain size, composition and porosity of sandstones in southern Alberta are significantly different from those of sandstones in world-class sandstone-hosted uranium districts. Additional studies of uranium emplacement in the clastic rocks of southern Alberta are needed to understand the history and potential of uranium enrichment.

The comprehensive petrographic data in this report will have applications in geological mapping and stratigraphic studies, as well as evaluations of mineral and hydrocarbon potential, of Upper Cretaceous and Tertiary rocks in southern Alberta.