Evolution of EM techniques to the exploration for unconformity uranium deposits, Athabasca Basin, Saskatchewan, Canada

Abstract:

Airborne and ground EM techniques have been applied to the exploration for unconformity uranium deposits as found in the Athabasca Basin, Saskatchewan, Canada since the 1970s. While earlier techniques were only required to penetrate 100- 200 m of sandstone cover, exploration for new deposits now takes place where the sandstone cover is well in excess of 500 m thickness. This has presented significant challenges to both the acquisition and processing of EM data in order to reliably image conductive features in the basement. Currently, for airborne techniques, Afmag appears to be the superior approach and for ground based surveys, SQUID sensors provide an advantage over traditional coil based receivers. Results over several deposits located at varying depths of sandstone cover will be examined.