A GIS dataset of geological features for the Red Fern Lake area (94 G/5), British Columbia

Abstract

The geological map and database are derived from regional mapping in the Redfern Lake (NTS 94G/5) 1:50 000 scale map area, as part of the Geological Survey of Canada's Central Foreland NATMAP project. Geological features represented by attributed points, lines, and polygons have been compiled into a GIS dataset suitable for stand-alone use, or integration with other data sets. User-defined attributes provide traditional geological map information with greater detail and enhancements. Redfern Lake map area encompasses the transition from the Foothills to the Main Ranges of the northern Rocky Mountains of northeastern British Columbia. The Foothills are underlain by late Paleozoic and Mesozoic rocks that are deformed into long linear folds with minor thrust faults, all detached on a basal decollement in the underlying Besa River Formation. The Main Ranges in the western part of the map area are underlain by lower Paleozoic limestones, dolostones and quartzites emplaced by large, shallow-dipping thrust faults onto the Besa River Formation. The dolostones are internally deformed by smaller thrust fault. The limestones contain tight overturned folds with penetrative cleavage. Whereas the early Paleozoic rocks are dominated by thick panels of carbonate rocks, the late Paleozoic and younger units are dominated by clastic rocks with subsidiary but economically significant carbonates in the Carboniferous Prophet (Debolt) Formation and the Triassic Charlie Lake, Baldonnel and Pardonet formations. Broad glacially scoured river valleys cut through the ranges. Some of these valleys are occupied by transverse faults which accommodate differential shortening and/or structural transitions at depth.