REPORT OF THE SECRETARY 7 



GEOLOGICAL EXPLORATIONS IN THE CANADIAN ROCKIES 



My geological field work in the Canadian Rocky Mountains, de- 

 scribed in previous reports, was continued during the past year, 

 special attention being given to securing evidence bearing on the 

 pre-Devonian formations north of the Bow Valley, Alberta, and 

 south along the new Banff -Windermere motor road. Difficulties were 

 encountered during the first part of the season, owing to dense 

 forest-fire smoke and unsatisfactory trail men, but during August 

 and September conditions were greatly improved and the work was 

 pushed vigorously. 



A fine section of pre-Devonian strata was studied and measured 

 in the upper part of Douglas Lake Canyon Valley, and many pho- 

 tographs were secured. The measured geologic section was from the 

 base of the Devonian, above Lake Gwendolyn, across the canyon to 

 the deep cirque below Halstead Pass, where the great Lyell lime- 

 stone forms the crest of the ridge. The section includes the Ozarkian 

 Mons formation down to the Lyell formation of the upper Cambrian. 



Going south from the Bow Valley, camp was next made on the 

 Kootenay River, about 6 miles below the mouth of the Vermilion 

 River. The Kootenay Valley is broad and deep, with the high 

 ridges of the Mitchell Range on the east and the Brisco Range on 

 the west. The limestones and shales of both ranges are upturned and 

 sheared and faulted, making it very difficult to work out the structure 

 and the complete stratigraphic succession of the various formations. 

 The Silurian limestones, with their fossil coral beds above the white 

 quartzite of the Richmond transgression, were found in the upper 

 portion of Sinclair Canyon, and not far away black shales full of 

 Silurian graptolites. Lower down the canyon thin-bedded gray 

 limestone yielded fossils of the Mons formation. 



It is evident that in the ancient and narrow Cordilleran Sea, that 

 extended from the Arctic Ocean 2,000 miles (3,218 km.) or more 

 south, between the coast ranges of the time and the uplands of the 

 central portion of the North American continent, there was a sim- 

 ilarity of Lower Paleozoic marine life along the shores and its shal- 

 low waters. Evidences of this and of strong currents and persistent 

 wave action occur all the way from central Nevada to Mount Robson, 

 in British Columbia. The record of the marine life and deposits 

 of mud and sand is most complete. 



PALEONTOLOGICAL FIELD WORK IN TENNESSEE 



Dr. R. S. Bassler, curator, division of paleontology of the United 

 States National Museum, spent six weeks in June and July in a con- 

 tinuation of stratigraphic and paleontologic studies begun a year 

 before in the central basin of Tennessee, in collaboration with the 



