Page:Walcott Cambrian Geology and Paleontology I.djvu/18

Future Work.—It is desirable that the Lower Cambrian strata of Fairview and Saddle Mountains near Laggan should be studied carefully; also that the area northwest of Mt. Bosworth and west of Mt. Daly should be examined for Upper Cambrian and Lower Ordovician formations and fossils. Exhaustive collections should also be made at many stratigraphic horizons.

Nomenclature.—Mr. McConnell proposed the name "Castle Mountain Group" for the great series of limestones and shales between the quartzitic sandstones and siliceous shales of the "Bow River Group" below and the superjacent Ordovician graptolitic shales on the west and Banff limestone on the east. This includes the upper portion of the Lower Cambrian fauna at the base and the lower portion of the Ordovician fauna at the summit. The term "Castle Mountain" is useful for the series, but I think that local names can be applied with advantage to several of the formations of the "Castle Mountain Group" as originally defined. The following table gives the relative positions and thicknesses of the new formation names herein proposed and defined for the Canadian Rocky Mountain section:

	Thickness (in feet).
	Mt. Stephen.	Mt. Bosworth.	Castle Mt.
Upper Cambrian:
Sherbrooke formation	0	1,360	0
Paget formation	0	0,360	0
Bosworth formation	Not measured	1,855	0
Middle Cambrian:
Eldon formation	Not measured	2,733	2,195
Stephen formation	562	0,640	0,366
Cathedral formation	1,600–1,800	1,595	0,987
Mt. Whyte formation[E 1]	315	0,390	0,248
Lower Cambrian:
St. Piran formation	300+	300+	500+
Lake Louise formation	......	......	......
Fairview formation	......	......	......

Sherbrooke Formation.

Type Locality.—Western slopes of Mt. Bosworth, overlooking Sherbrooke Lake, Canadian Rocky Mountains, five miles north of Hector, on the Canadian Pacific Railway, British Columbia.

Derivation.—From Sherbrooke Lake, below the typical locality.

Character.—Bluish gray, arenaceous, dolomitic, massive, and thin-bedded to shaly limestones, with a few oolitic layers and cherty inclusions.

Erratum

1. The Mount Whyte formation which is placed in the Middle Cambrian on page 2 should be in the Lower Cambrian as indicated on page 4.