Upper Cretaceous in Western Peace River Plains, Alberta

Abstract

The territory covered includes approximately 3,600 square miles of Plains area in north-central Alberta. The area is approximately 500 miles northwest of Edmonton, and its western edge parallels the Alberta-British Columbia boundary. The strata described comprise nearly 3,000 feet in the west, to 2,000 feet in the east, of Upper Cretaceous formations including, in ascending order, the Dunvegan, Kaskapau, Cardium (Bad Heart), Wapiabi, and basal Member A of the Wapiti. Within the area, the name Smoky River is raised from formational to group rank and includes the Kaskapau, Cardium, and Wapiabi formations. A White Speckled Shale zone was observed in the Kaskapau and another in the Wapiabi. It is suggested that the term Cardium as a formational name be extended eastward onto he plains and that it embrace the Bad Heart sandstone along Smoky River. The term Chinook is applied to a littoral marine sandy shale and sandstone member in the upper part of the Wapiabi shales. Both Ammonite and Inoceramus fossil zones are listed and correlated from west to east. Formational thicknesses are compiled from isolated outcrops. The formations thin notably eastward, particularly in the Smoky River group.