Preliminary bedrock geology for NTS 95D/6 (Otter Creek area), southeast Yukon.

The Otter Creek area contains sedimentary and volcanic strata of the ancient North American miogeocline: Neoproterozoic to Lower Cambrian shale (Narchilla Formation) and siltstone (Vampire Formation); Late Cambrian to Middle Ordovician argillaceous to massive limestone (Rabbitkettle Formation) and dolostone (Sunblood Formation); Cambrian to Ordovician basalt and associated diabase; Silurian to Devonian MacDonald carbonate platform strata (unit SDc-south) and Selwyn basin shale (Road River Group-north); and thinly bedded silty shale likely of the Devonian to Carboniferous Besa River Formation. The rocks are deformed by six mappable north-trending, east-verging, asymmetric, macroscopic folds with amplitudes of 500-2000 m. Argillaceous and silty units contain a pervasive, axial-planar slaty cleavage. Shortening caused by the folding is about 25%. The Narchilla Formation is structurally emplaced upon Upper Cambrian-Devonian sedimentary rocks on the western margin of the map area, along an east-verging thrust fault with unknown displacement. Late northeast-striking normal faults preserve younger stratigraphic units to the south. Deformation is poorly constrained to the…

Publisher

Government of Yukon

Resources

3

Catalogue metadata updated

2026-08-26