MINERAL AND LITHOLOGIC MAPPING IN NORTHEAST ALBERTA USING WORLDVIEW-3 SUPER-SPECTRAL IMAGERY

The Canadian Shield in NE Alberta is one of the primary areas of U, REE, and base metal potential; however, the location of occurrences documented during the pre-GPS era in the 1960s and 1970s are not as precise as what can now be achieved with advanced global positioning systems. WorldView-3 super-spectral imagery is utilized in this study to detect mineral anomalies and locate known occurrences of U, REE, and base metals concentrated in narrow belts surrounding several major shear zones in NE Alberta. These mineral occurrences are associated with alterations such as weathered sulphide horizons, quartz-tourmaline metasediments, and pegmatites. Mineral indices based on Fe3+, Fe2+, -OH, Fe-Mg, clay/carbonate, and mafic-felsic are used to understand mineral anomalies and lithologic variations to guide fieldwork. A preliminary analysis using indices, Spectral Angle Mapper (SAM), and Sequential Maximum Angle Convex Cone (SMACC) reveals a suite of felsic units and metasediments in the Tulip Lake area. These units appear to conform with the localized distribution of known map units providing a first-order validation of the interpretations. Reconnaissance-level fieldwork was performed to collect spectral signatures across a broad set of lithologies, alongside a traditional field mapping crew. Additionally, field crews sought to locate, describe, sample, and collect spectra near known geochemical and spectral anomalies. Features of interest included pegmatites, gossan, high radioactivity, elevated concentrations of REEs or U, yellow-green chlorite staining, and Cu/Ag/Ni mineralized zones. Field data is currently being used to construct a spectral library and calibrate a satellite-based linear mixture model of minerals. The analysis will also help large-area land-use planning and the identification of potential areas for critical mineral exploration.