Near Pincher Creek, Alberta, the leading edge of the Canadian Cordillera approximates a triangle zone geometry with both wedge and duplex characteristics. Shortening across the wedge area is estimated at approximately 35%, most of the displacement having occurred across low-angle thrust ramps and flats that offset Jurassic to Upper Cretaceous-age strata. A detachment extends eastward from the wedge tip for a minimum of 14 kilometres under the foreland, across which several kilometres of shortening may have been accommodated by backthrust and duplex mechanisms within the hanging wall of the upper detachment. Folded Tertiary-age strata indicate that triangle zone development continued through Paleocene time. Other wedge geometries have been identified west of the leading edge, suggesting that triangle zone development occurred throughout the Laramide Orogeny. Locally, no commercial hydrocarbon production occurs from the triangle zone; however, both source and elastic reservoir rocks are carried in the wedge, with potential trapping geometries.