Neoproterozoic-Cambrian stratigraphy of the Mackenzie Mountains, northwestern Canada, part III: measured sections from Neoproterozoic and Cambrian formations, NTS 96-D

Abstract

Four previously undescribed measured sections are documented through lower and middle Cambrian (Series 2 and Miaolingian) strata of the eastern Mackenzie Mountains, Northwest Territories. These include three exposures of the Mount Clark Formation that are complete or nearly so, and a complete section through the overlying Mount Cap Formation. As in previous reports, Mount Clark Formation is dominated by quartz arenite, with variable bioturbation. Mount Cap Formation is heterolithic, dominated by dark-weathering shale and paler-coloured carbonate rocks. A section through the Neoproterozoic McClure Formation (Katherine Group) also is included, and contains abundant fine-grained siliciclastic strata with lesser sandstone and a distinctive orange-weathering carbonate. Correlations between these sections and one previously documented show the influence of late Neoproterozoic folding, reflected in erosional truncation of the McClure Formation beneath the Cambrian succession, as well as stratigraphic variations in the Cambrian units that reflect the influence of the Mackenzie Arch.