186 EDWARD STEIDTMANN ~ 
The source of this great thickness of sediments, Daly believes, 
is the older pre-Beltian terrane, the principal evidence for this 
being the graduation of coarser sediments to finer in going from 
west to east. Another fact in favor of this is that the quartzites 
commonly contain fragments of alkaline feldspar. The quartzites, 
he believes, are partly dune and loess deposits. The limestones, 
because of their fine grain, he ascribes to direct chemical precipi- 
tation. Most of the sediments are well bedded and consist chiefly 
of quartz, striated feldspar, and clayey material. Frequently, 
they show ripple marks and mud cracks. 
The Roosville, Phillips, and Rateway’ formations classified by 
Daly in his forty-ninth parallel report as Middle Cambrian are 
assigned by Schofield to the Beltian because the Roosville is uncon- 
formably overlain by the fossilferous Middle Cambrian Burton 
formation. Both the Purcell and the Galton series of Daly are 
placed in the pre-Cambrian. 
The unconformity between the Burton and the Roosville is not 
shown by discordance of bedding, but by a basal hematite con- 
glomerate of the Burton, the occurrence of other materials in the 
Burton which are inferred to have been derived from the Roos- 
ville, the striking difference in the metamorphism of the Burton as 
compared with the formations underlying it, and the occurrence of 
cryptozoan forms in the formations underlying the Burton. 
Schofield? describes the Cranbrook area of southeastern British 
Columbia. 
The area is in the southern part of the Purcell Mountains and 
includes about 50 square miles. The Beltian pre-Cambrian rocks 
underlie most of the area. Schofield’s classification of these rocks 
follows. 
1S. J. Schofield, “‘The Pre-Cambrian (Beltian) Rocks of Southeastern British 
Columbia, and Their Correlation,’ Canada Geol. Surv. Mus. Bull. No. 2 (July 3,1914), 
PP. 79-91, 1 fig. (map). 
2S. J. Schofield, ‘‘Geology of Cranbrook Map-Area, British Columbia,” Canada 
Geol. Surv. Mem. No. 76 (1915), 245 pp., I map, 33 pls., 15 figs. 
