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TitreSpectral analysis of gossans on Victoria Island, NT, Canada: implications for remote predictive mapping
AuteurPercival, J B; Williamson, M -C; Harris, J; Froome, J; Peterson, R
Source33rd Canadian Symposium on Remote Sensing, abstracts; par Canadian Symposium on Remote Sensing; 1049, 2012 p. 49
LiensOnline - En ligne
LiensAbstracts (PDF, 1.22 MB)
Séries alt.Secteur des sciences de la Terre, Contribution externe 20120324
Réunion33rd Canadian Symposium on Remote Sensing; Ottawa; CA; juin 11-14, 2012
Mediaen ligne; numérique
ProvinceTerritoires du Nord-Ouest
SNRC87; 97
Lat/Long OENS-116.0000 -104.0000 72.0000 69.0000
Sujetschapeaux ferrugineux; géochimie du sol; géochimie des éléments en trace; géochimie du pergélisol; analyses à l'infrarouge; gypse; goethite; jarosite; filons-couches; minéralogie; géochimie
ProgrammeOutils d'adaptation et d'impacts sur l'environnement pour les mines de métaux, Géosciences de l'environnement
Résumé(disponible en anglais seulement)
Gossans are highly weathered Fe-rich soils that overly sulphide-rich materials, and can be used as exploration targets for base metal deposits. A 3-year activity in the Environmental Geosciences Program (Earth Sciences Sector) is investigating the stratigraphy, mineralogy and geochemistry of arctic gossans as analogues for mine waste in permafrost. The objective is to document the fate of toxic trace elements such as As, Cd, Co, Cu, Ni and Pb in the soils and permafrost surrounding gossans. Remote Predictive Mapping (RPM) has confirmed the presence of gossans in central Victoria Island, Northwest Territories. As a result, several sites were investigated during the 2011 field season. This paper compares infrared spectral analyses taken in situ using a portable spectroradiometer (FieldSpec Pro® ASD, Inc.) with follow-up laboratory measurements for two stations. Station 1, Gossan Hill, is a 400-m topographic high capped by a poorly-consolidated rust-coloured gossan overlying homogeneous pyrite-rich sands. Spectral analyses indicate abundant gypsum, goethite and jarosite minerals, and X-ray diffraction confirms them as well as minor amounts of quartz, mica, talc and feldspar. Station 2, Gossan Sill, underlies a mineralized sill consisting of sulphide-rich veins and pods. Spectral analyses show gypsum and jarosite and XRD indicates variable amounts of goethite, hematite, pyrite, chlorite, calcite and feldspar. The results from in situ surface spectral analyses are robust, and will improve the predictive map based on LANDSAT 7 images. Importantly, they will reduce existing gaps between mapping and exploration cycles and the environmental assessment process critical for sustainable northern mineral development.