NO. 5 PRE-DEVONIAN PALEOZOIC FORMATIONS 357 



of tying in the collections to the sections was undertaken. A number 

 of the most essential lots from a stratigraphic standpoint were found 

 to be merely comminuted fragments of no diagnostic value, while 

 others were evidently rough pieces that might afiford something of 

 service when broken up and the fragments identified. 



Burling did not publish his detailed field sections or list the fossils 

 occurring in them. He made many generalizations, but did not present 

 the evidence on which they were based. 



My reconnaissance section of 191 2 was written out and published 

 in July, 191 3, just as I was going in over the new trail to Robson 

 Peak and Berg Lake for the purpose of collecting fossils from the 

 limestones of Billings Butte and the Lower Cambrian of Mumm Peak 

 and to take photographs. While camped on Rainbow Brook below 

 Lake Kinney at the southwest base of Robson Peak, a brief study was 

 made of the western side of the Robson massif where one of the great 

 geologic sections of the lower Paleozoic formations in the Cordilleran 

 Geosyncline is exposed to view. On its southwestern side the evenly 

 bedded limestone and shales rise clifif above cliff, from the flat at the 

 head of Lake Kinney to the apex of the peak, 9,752 feet (2,972.4 m.) 

 above (pi. 99). To the thickness of strata from the summit to the 

 level of Lake Kinney, there should probably be added a thickness of 

 about 2,200 feet (670.6 m.) resulting from the 10° inward slope of 

 the strata from Lake Kinney Flat to a point beneath the center of 

 the peak, a horizontal distance of 2.5 miles (4 km.). 



From beneath the western base of the limestone series of the peak, 

 Lower Cambrian sandstones slope upward gently and then more 

 steeply until the base of the Cambrian impinges at a high angle against 

 the Miette sandstones of the pre-Cambrian (pi. 96). Altogether there 

 are about 12,000+ feet (3,657.6+ m.) of strata in sight from below 

 the outlet of Lake Kinney. Viewed from the outcrop, the northeast 

 dip of the beds into the mountain is not noticeable along the strike, 

 but seen from the south or north, one is soon convinced that the 

 Robson massif is a syncline with the apex of the peak not far from 

 its center. 



Approaching the peak from the southwest, the Lower Cambrian 

 sandstones are seen sloping north with a dip of about 30°, and frag- 

 ments of Olenellus were found about 100 feet (30.5 m.) above the 

 lake ; on the southwest side of the lake, the sandstones dip northeast 

 45° to 60° to 63° as they approach the contact with the pre-Cambrian 

 Miette beds on the summit of Robson west station of the Wheeler map 

 of 1911 (7,290 feet, 2,222 m.), which is southwest of Lake Kinney. 

 (See pi. 106, looking north-northeast over the lake.) On the south the 



