157 



^Hes^and^ granite; a granodioritic composition appears to 

 be more characteristic of gneissic phases of the 

 Laurentian, which contain partly assimilated 

 Keewatin inclusions. 



The spur leading southward from the main 

 line near Pelican connects with a mine on 

 Vermilion lake, where a large vein of pyrite is 

 being developed. 



252m. Graham — Altitude 1,189-4 ft. (362-6 m.). 



403-2 km. Between Graham and Superior the schists are 

 covered by stratified clay similiar to that seen 

 in Wabigoon valley and probably laid down in 

 a former expansion of Sturgeon river. The 

 rocky banks farther upstream show numerous 

 large potholes from 10 to 15 feet (3-5 metres) 

 above the present level of the river, indicating 

 its former volume to have been much larger 

 than the present one. A narrow belt of closely 

 folded Lower Huronian conglomerate and grey- 

 wacke follows the course of Sturgeon river, but 

 is hidden beneath the stratified clay, where the 

 railway crosses the river just west of Superior. 



258-4 m. Superior — Altitude 1,190 ft. (362-9 m.). 



413-4 km. Keewatin schists give place to the Laurentian 

 gneiss near Rosnel. Keewatin rocks are once 



more traver- 



267-9 m. Rosnel — Alt. 1,180 ft. (359 •9m.) sed in the 



428-6 km. next 51 miles 



(81-6 km.), but there is little of geological in- 

 terest to be seen in this distance. At the 

 Laurentian-Keewatin contact, 3-7 miles (5-9 

 km.) east of Staunton, the schists are derived 

 from acid eruptives and exhibit much less con- 

 tact metamorphic effects than is the case with 

 basic materials where so close to the Laurentian 

 intrusives. 



The greatest elevation (1,457 ft. 444-1 m.) 

 on the railway between Winnipeg and Lake 

 Nipigon is attained 3 miles (4-8 km.) east of 

 Bucke. 



312 -4 m. Bucke— Altitude 1,401 ft. (427-3 m.). The 



499-8 km. first erosion remnant of Keweenawan diabase 

 is passed 2 miles (3-2 km.) east of Harvey. 

 Such vestiges of diabase sills become larger and 



