Porcupine Hills Formation

The Porcupine Hills Formation is a middle to late Paleocene geological unit in southwestern Alberta within the Western Canada Sedimentary Basin. Named for the Porcupine Hills and first described by George Mercer Dawson in 1883, it consists mainly of river and floodplain mudstone, siltstone, and sandstone eroded from the rising Canadian Cordillera during the later Laramide Orogeny. It extends from the Waterton River near the Canada–US border to the Bow River near Calgary and reaches a recorded maximum thickness of 1,200 metres. Its lack of coal beds, unlike the equivalent Paskapoo Formation farther north, has been used to suggest a drier, semi-arid Paleocene climate in this part of Alberta.

Alberta · Canada