CAMBRIAN GEOLOGY AND PALEONTOLOGY 



Xo. I.— NOMENCLATURE OF SOME CAMBRIAN CORDIL- 

 LERAN FORMATIONS 



By CHARLES- D. WALCOTT 



In connection with the preparation of the section on the strati- 

 g-raphic distribution of the Cambrian Brachiopoda for Monograph 

 LI, of the L^. S. Geological Survey, I find that it is necessary to refer- 

 to many undefined Cambrian formations of the Cordilleran area. 

 The present paper is published for the information of geologists and 

 for the purpose of properly defining and characterizing the forma- 

 tions in question, as the first reference to these formations should be 

 accompanied by more information than can" well be included in the 

 pages of the monograph. 



CANADIAN ROCKY MOUNTAINS . 



Since reading, in 1886, j\Ir. R. G. McConnell's report of 18B5 on 

 his section across the Rocky Mountains in the vicinity of the 51st 

 parallel,^ I have had a strong desire to study the stratigraphy of the 

 Cambrian portion of the section. It was not until the sununer of 

 1907 that the opportunity came. Accompanied by Mr. Lancaster D. 

 Burling as field assistant, a study was made of the typical Castle 

 ?^Iountain section of Mr. ]\IcConnell, the lower portion of the Mt. 

 Stephen and Mt. Whyte sections, and the full section pi Mt. Bos- 

 worth, on the Continental Divide, which proved to be the most 

 complete. 



Except where otherwise stated, the sections were carefully meas- 

 ured with rod and clinometer. The strata were so well exposed 

 that it was rarely necessary to go any distance to avoid talus slopes 

 and covered portions of the section. Collections of fossils were made 

 at many horizons, but, owing to the limited time available, this part 

 of the work was neither systematic nor exhaustive. 



Location. — The area examined is on the line of the Canadian 

 Pacific Railway between the Sawback Range on the east and the 

 Van Horn Range on the west. In this limited area there was only 

 time for the examination and measurement of the strata of Castle 

 Mountain and Mt. Bosworth, the lower 3,800 feet of the Mt. Stephen 

 section, and the Lower Cambrian formations on the slopes of Mts. 

 Whyte and St. Piran, in the vicinity of Lakes Louise and Agnes. 



' Geol. and Nat. Hist. Survey of Canada. Ann. Rept., 1886, Part D, pp. isD- 

 30D, 1887. 



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