| Résumé | (disponible en anglais seulement)
Between 1980 and 2008, Canada's metal reserves experienced a continuous decline, resulting in levels that are less than half of those reported at the end of
1980. A key aspect contributing to this decline is the increasing rarity of surface discoveries in Canada , forcing the exploration industry to search deeper for new resources. As existing mining camps have already proven that their geology is
favourable for deposition of metals at high enough concentration s to form ore bodies, there is a higher probability that other ore bodies exist in these camps . As such, these regions should be best situated to benefit from fundamental geoscience
knowledge that expands the volume, and not just area, of exploration. In light of this, NRCan renewed the Targeted Geoscience Initiative (TGI - 4) in 2010 for 5 years with a budget of $25 M. The program focuses on providing industry with the next
generation of innovative geoscience knowledge and analytical techniques that will result in more effective targeting of buried mineral deposits, thereby increasing discovery rates. TGI - 4 is a national program that carries out projects under seven
ore systems (Lode Gold, Ni - Cu - PGE - Cr, VMS, Intrusion Related, SEDEX, Uranium and Specialty Metals) as well as methodology development projects. In Saskatchewan, TGI - 4 has focused its program on demarcating key markers of U enrichment related
to the basement - sandstone unconformity in the Athabasca Basin and comparing them to similar U deposits across the country. Collaborative projects between government, academia and industry are examining unconformity - related U ore systems in the
Proterozoic Athabasca (Phoenix, Millennium McArthur River and Dufferin Lake zone), Thelon (Bong) and Otish (Camie River) basins in order to refine genetic models and exploration tools for these U deposits. Studies on graphite depletion in the
Dufferin Lake zone, numerical hydrodynamic modelling coupled with detailed 3D models of the basin and petrological, geochemical and isotopic studies of intense alteration associated with deposits and ore - hosting faults are all resulting in new
knowledge leading to better geological - based exploration models. Complementary to enhanced geological models, TGI - 4 is also developing new methods for vectoring to deposits. These include the use of Fe and Mg isotopes as markers of U
mineralization and enhance d accuracy and sensitivity of airborne radiometric plus geochemical methods for deeply - buried (ca. 600 - 750 m) U deposits. The latter methods have shown that not only do anomalous element concentrations in the uppermost
sandstone units delineate fertile structures on regional scales, but elevated metal contents in surficial media and radiogenic gases in groundwater coincide with projections of the reactivated shear zones and deeply - buried ore bodies. TGI - 4
results from across the country are also applicable to base metal and gold deposits in Saskatchewan. For example, a methodology development project based on seismic imaging of the Lalor deposit in Manitoba, has enhanced the ability, utility and cost
- effectiveness of these geophysical surveys in delineating base metal ore deposits , as well as 3D models to visualize them. |