174 ENVIRONMENT OF VERTEBRATE LIFE, ETC. 



About 100 miles to the north and northwest of the boundary section at 

 the Pend d'Oreille are found considerable areas of stratified rock which 

 Brock referred to the Cache Creek series, or the Slocan series, which he 

 regards as equal to the Cache Creek. 1 



In the Flathead Valley there is, according to Dowling, 2 a "down-tilted 

 block " * of Carboniferous limestone with reddish upper beds that may 

 be Permian or Triassic in the higher members." This lies due south of 

 Corbin, at the mouth of Squaw Creek. 



AtBlairmore, in the South Fork River coal area, MacKenzie 3 describes a 

 small area of pure and cherty limestone. Similar beds occur in the anticline 

 of the Turtle Mountains. The age of this bed is uncertain, but is pro- 

 visionally placed as Devono-Carboniferous. 



On the eastern edge of the Rocky Mountain Front, in the Sheep Creek 

 anticline, on Sheep Creek south of Clagary, Alberta, Dowling 4 describes 

 Mesozoic rocks and continues (page 149)": 



"It is quite certain that the floor on which the above-described Mesozoic 

 deposits were laid down consists of a series of limestones of which the western 

 portion is formed of Carboniferous rocks with possibly some Triassic and Permian 

 sediments lying here and there upon them." 



"The Cache Creek formation, as shown on the present map and as now 

 understood, must therefore be regarded as including a very thick series of Paleo- 

 zoic rocks, of which the greater part is definitely referable to the Carboniferous 

 period by means of its fossils, but of which it is scarcely probable that the upper 

 and lower limits agree precisely with those of the typical Carboniferous. It may 

 very possibly be found at the base, particularly, to transgress these limits and 

 to include beds older than those of the system. 



"In attempting a brief general description of this formation, it must in the 

 first place be observed that the extremely broken and disturbed character of the 

 rocks almost everywhere renders it next to impossible to learn much about their 

 attitude or sequence in any one locality. It is very generally impossible to deter- 

 mine whether the dip of the beds is normal or has been overturned. It is thus 

 only by following the general association of the rocks from place to place and by 

 piecing together facts observed at many different places that it becomes prac- 

 ticable to outline the salient features of the whole. 



"The western part of the Kamloops sheet, between the Thompson and Bona- 

 parte Rivers on one side and the Fraser on the other, is the typical area for the 



1 Brock, R. W., Explanatory Note to the West Kootenay Map Sheet, Canadian Geological 



Survey, 1902. 

 * Dowling, D. B., Coal Areas in the Flathead Valley, British Columbia, Summary Report 



of the Geological Survey of Canada for 1913, p. 139, 1914. 

 1 MacKenzie, J. D., South Fork Coal Area, Oldman River, Alberta, Summary Report 



Canadian Geological Survey for 1912, p. 235, 1913. 

 4 Dowling, D. B., Geological Notes on the Sheep River Gas and Oil Field, Alberta, Summary 



Report Canadian Geological Survey for 1913, p. 145, 1914. 

 6 This account is taken from Professional Paper No. 71, United States Geological Survey, 



page 390. It is a condensation of reports by G. M. Dawson, Report on the Kamloops 



Sheet, British Columbia, Annual Report of the Canadian Geological Survey, new series, 



vol. 7, page 39, 1896, and Duplication of Geologic Formation Names, Science, n. s., 



vol. 9, page 592, 1899. 



