Open File Report 2009-19

Open File Report 2009-19

OFR 2009-19

Overview of Uranium Exploration Work along the Northern Rim of the Athabasca Basin, Northeastern Alberta

Author(s) Pana, D.I. Olson, R.A. Date 2009-10-26

In Alberta, the northern rim of the Athabasca Basin and the regolith underlying the Athabasca unconformity is locally exposed along the northern shore of Lake Athabasca. Extensive uranium exploration work in the 1970s, including scintillometer prospecting traverses, geological mapping, airborne and ground geophysics, and drilling, have documented several uraniferous outcrops with 10 000 counts per second, and uraniferous boulder trains or individual boulders with up to 16 000 counts per second. Near the Alberta-Saskatchewan border, uraniferous boulders show geochemical characteristics consistent with a Saskatchewan source, where as to the west boulders have a distinct geochemical signal suggesting a local source in Alberta.

Six days of float plane-supported field work in August 2004 confirmed the location of the Athabasca unconformity along the northern shore of Lake Athabasca. Scintillometer traverses over previously defined radioactive boulder fields, and examination of the locations where individual radioactive boulders were reported, resulted in the identification of only a few slightly radioactive (200 to 400 counts per second) sandstone boulders near Fallingsand Point, suggesting that the vast majority of the uraniferous boulders initially discovered may have been collected for further analyses during the intense exploration in the 1970s. Uranium metallogenetic indicators extracted from industry assessment reports (location of boulder fields and individual boulders, drillhole locations), as well as mineral occurrences (including many uraniferous sites) identified north of Lake Athabasca by the provincial and federal geological surveys, have been compiled in GIS format. Articles relevant to uranium exploration in the Athabasca Basin have been reviewed in light of new data generated during the ExTech multidisciplinary and multi-agency project (2000-2005), in an attempt to extract exploration hints for future uranium exploration work in northeastern Alberta.