Shallow crustal structure of the Tehery Lake–Wager Bay area, western Hudson Bay, Nunavut, from potential-field datasets

The Tehery-Wager geoscience mapping activity is a multiyear initiative conducted by the Geological Survey of Canada (GSC) and Canada-Nunavut Geoscience Office (CNGO) under the second phase of the Geo-Mapping for Energy and Minerals (GEM-2) program. The second of two field seasons included two ground gravity transects that complement the existing aeromagnetic coverage by providing information on the subsurface geology, and highlight the structure and geometry of the Wager shear zone (WSZ) and Chesterfield fault zone (CFZ). Preliminary processing of gravity data reveals discontinuities in the observed gravity field correlative with these major structures and mapped lithological units. On both gravity transects, the CFZ corresponds to a prominent gravity low and magnetic textural discontinuities. Contrasting potential-field signatures associated with two distinct supracrustal assemblages offer additional insight for remote discrimination. Associations between gravity and magnetic anomalies, physical rock properties and mineral occurrences have the potential to constrain the regional distribution of economically significant horizons.