320 DEPARTMENT OF THE INTERIOR 



2 GEORGE V, A. 1912 



The igneous formations to be treated include those which have been named 

 by McConnell and Brock the Rossland and Beaver Mountain volcanic groups ; 

 and those which are referred to by the present writer as the Trail batholith; the 

 Sheppard granite (stocks and dikes) ; the Coryell syenite batholith with its 

 satellitic dikes, and a satellitic chonolith of syenite porphyry; the Rossland 

 monzonite; several bodies of gabbroid and ultra-basic intrusives; and certain 

 of the numerous dikes which have certain special petrographic interest. 



At the time when the writer made his examination of the Rossland moun- 

 tain group it was understood that the Geological Survey of Canada was planning 

 a detailed study of the Rossland camp and its vicinity. Accordingly, very little 

 work was done in the region of the town and, in fact, no attempt was made to 

 plan an exhaustive report for the region between Sophie mountain and the 

 Columbia. Specimens of the rocks were collected, but many of the field rela- 

 tions could not be decided in the limited time which it seemed advisable to devote 

 to this part of the Boundary belt. Nearly all of McConnell's contacts, as pub- 

 lished in the Trail sheet, were followed up and verified. For the rest the present 

 chapter can claim to be no more than a report of progress on the geology of these 

 unusually complicated mountains. 



Paleozoic Formations. 



Carboniferous Beds in Little Sheep -Greek Valley. — In the bottom flat of 

 Little Sheep creek valley, about 1,000 yards north of the Boundary line and 

 on the west side of the creek, there is a low hill of limestone surrounded on all 

 sides by alluvium. The limestone is of blue-gray to white colour and is much 

 brecciated and highly crystalline. It contains cherty and quartz lenses and true 

 quartz veins. The attitude of the bedding is obscure, observed strikes ranging 

 from N. 55° E. to N. 80° E., with an average northerly dip of about 60°. 

 The limestone contains numerous, poorly preserved crinoid stems which are 

 of some value as pointing to the probability that the limestone is of Paleozoic 

 age. Across the creek there are several large outcrops of cherty quartzite also 

 greatly deformed, with average strike, N. 35° E. and dip, 90°. That rock 

 extends 200 feet vertically up the steep eastern slope of the valley, where it is 

 unconformably overlain by a coarse breccia (probably a volcanic explosion- 

 breccia) containing fragments of the same obscurely fossiliferous limestone 

 and chert as that just described. The breccia is part of the Rossland volcanic 

 formation, which has here an average strike, N-S. and dip, 35° E. From the 

 composition of the breccia and from the stratigraphic relations, the Rossland 

 volcanics as represented are clearly unconformable to the Paleozoic strata. The 

 latter seem, in fact, to be part of the foundation on which the volcanic mass was 

 spread. 



During his mapping of the Trail sheet McConnell found in the similar 

 breccia outcropping on the opposite side of this valley, fragments of marble 

 bearing the fossil remains of a species of Lonsdalia and the marble was referred 

 by Dr. Whiteaves to the Carboniferous. It would seem simplest directly to 



