Geology of Elu Inlet and Melville Sound, Nunavut, Arctic Canada

We present the results of helicopter- and field-based geological mapping of Elu Inlet and Melville Sound, Kitikmeot Region of Nunavut, Arctic Canada. The area includes a ∼150 km-wide belt of Proterozoic sedimentary rocks that unconformably overlie the Archean Slave Province of the Canadian Shield and are cross-cut by Neoproterozoic mafic rocks and covered by early Palaeozoic deposits. This work introduces an updated sedimentologic, stratigraphic, and structural framework for the area and is corroborated by geophysical analysis of natural radioactivity. Three Proterozoic sedimentary sequences have been identified, spanning in age from ∼1.9 to ∼1.2 Ga, and including fluvial–aeolian sandstone and shallow-marine carbonate rocks. Mass-spectrometric analyses identified above-baseline concentrations of uranium along the unconformities underlying the two oldest Proterozoic sequences. Proterozoic deposits display weak deformation, related to syn-orogenic foreland and intracratonic-sag stages of the Kilohigok and Elu basins, respectively.