REGIONAL GEOCHEMICAL MAPPING OF OXIDE-SULPHIDE GOSSANS AND THEIR REACTIVE ZONES IN PERMAFROST, CANADIAN ARCTIC ARCHIPELAGO

Gossans associated with flood basalt magmatism in the Canadian Arctic Islands are natural laboratories to study the fate of potentially harmful elements such as As, Cd, Co, Cr, Cu, Hg, Ni, and Pb, that are released into the permafrost environment during the oxidation of sulphides. Remote predictive mapping, orientation surveys, and the mineralogical and geochemical studies on samples collected during field work contribute to bridging the gap between the mineral exploration and environmental assessment cycles in Canada’s North.

The objectives of the project (2011-2014) were to: (1) locate gossans in central Victoria Island and Axel Heiberg Island using satellite imagery; (2) measure the spectral signatures of surficial materials at key locations to improve the accuracy of remote predictive maps; (3) map and sample surface materials of alteration zones and stream sediments; (4) determine the stratigraphy, mineralogy, and geochemistry of protoliths, leach caps, gossans, and stream sediments. Gossans developed in volcanic terrain on Victoria Island and Axel Heiberg Island were mapped using a combination of LANDSAT, ASTER, SPOT5, and WorldView-2 satellite images.

Remote predictive maps were ground truthed during field work in 2011 and 2013. We report the results of detailed mineralogical and geochemical studies of the igneous protoliths, gossanous soils and stream sediments, with implications for environmental geoscience and metallogeny.