Abstract
The more important unsolved stratigraphic problems in the Waucobian and Albertan rocks of British Columbia in 1938 were: the geographic distribution and variation in thickness of the formations south and west of Ptarmigan and Castle Mountains; the origin and relationships of the Ptarmigan limestone to the Cathedral dolomite; the stratigraphic position of the Ross Lake (Albertella) shale on Mounts Bosworth and Assiniboine, and the Ogygopsis shale on Mount Stephen; and the position of the southern shores of the Cambrian sea on the north side of the Montana Island. The Mounts Bosworth and Assiniboine sections were remeasured and the Mount Stephen section was examined in 1939. The results are:
On Mount Bosworth the Ross Lake shale is well exposed 385 feet above the Ptarmigan limestone. The Eldon dolomite is 1110 instead of 2728 feet thick. The Lake Louise and Fort Mountain formations do not crop out, and only 750 instead of 2705 feet of St. Piran is exposed. The total thickness of the Mount Bosworth section is more nearly 6300 than 12,353 feet as originally reported.
The Ogygopsis shale seems to rest upon the Cathedral instead of beneath the Eldon on Mount Stephen, thus forming the lower instead of upper part of the Stephen formation. This problem remains unsolved.
The new Gog and Naiset formations are defined for the Waucobian and basal Albertan rocks in the Assiniboine section originally assigned respectively to the Fort Mountain, Lake Louise, and St. Piran, and Mount Whyte formations. The distribution and origin of the Ptarmigan formation are discussed.
Lower and Middle Cambrian geography and sedimentation are described, and the sections are correlated temporally with those in the Cordilleran area of the United States.
