Stratigraphy, structure and timing of deformation at the southern termination of the Western Ranges and Main Ranges of the Southern Canadian Rocky Mountains, near Fort Steele, British Columbia

Detailed geologic mapping in the Wild Horse River area, which straddles the southern termination of the Western Ranges and Western Main Ranges of the Southern Canadian Rocky Mountains, has augmented and refined the structural and stratigraphic interpretations previously proposed for this portion of the Crowsnest Pass Cross-Strike Discontinuity. The Wild Horse River map-area straddles two, fault-bounded, tectonostratigraphic domains: the Hughes Range domain with an attenuated sequence of thin, condensed, miogeoclinal strata that evidently was deposited on the flank of a paleo-topographic high, and the Tanglefoot domain with an extremely thick miogeoclinal succession that contains volcanic rocks and is inferred to have been deposited in a deep basin. The marked stratigraphic contrast between the domains suggests that they are far traveled with respect to each other.; Mafic volcanic rocks that are intercalated within the Cambro-Ordovician strata in the Tanglefoot domain of Wild Horse River map-area are anomalous. Mapping and characterization of these volcanic rocks suggests that they are related to diatremes that are scarce but regionally widespread. (Abstract shortened by UMI.)...