337 



ffiiometres are uncon f° rma bly overlain by conglomerate, 

 apparently of the Nanaimo series, and still 

 farther west in the valley of Chemainus river 

 the shales grade northward into the Sicker 

 schists. They are presumably of Jurassic 

 or Triassic age, but are indistinguishable 

 from the Nanaimo shales which occur to the 

 east below the drift-covered flat extending from 

 the railroad to the shore. 

 29-9 m. Somenos — Altitude 108 ft. (33 m.). From 



48-1 km. Somenos to south of Cowichan the railroad 

 crosses the large, maturely glaciated, subsequent 

 Cowichan valley, underlain by a closely folded 

 syncline of Nanaimo sediments, largely sand- 

 stones and shales. The valley is almost 50 

 miles (80 km.) long, and nearly divides the 

 southern part of Vancouver island. It is 

 glacially deepened, especially in its upper part, 

 where Cowichan lake lies. The Cowichan 

 river flows eastward from the lake, and for the 

 greater part of its course meanders in its flat 

 valley floor, some two to three miles wide, 

 between cut banks 10 to nearly 200 feet (3 to 

 60 m.) high, of stratified drift of inter-glacial 

 and post-glacial deposition, the river having 

 been revived by the recent uplift. At Somenos 

 is a brick plant using the inter-glacial clays, 

 which cover a large part of the lower portion 

 of the valley. 

 32-8 m. Duncan — Altitude 50 ft. (15 m.). Between 



52 • 8 km. Somenos and Duncan, to the east of the railroad, 

 is Somenos lake, formed in one of the partly 

 drained hollows in the inter-glacial clays. 

 East from Duncan is Mt. Tzuhalem, which is 

 capped by the basal conglomerates of the 

 Nanaimo series resting unconformably on the 

 Sicker schists and porphyrites. The southern 

 slope is a fault line scarp, developed along the 

 fault which has thrown the Sicker series up 

 against the Nanaimo series to the south. 

 Farther to the east is Saltspring island, com- 

 posed largely of the rocks of the Sicker series. 

 The greater part of the island has an elevation 

 of 1,500 to 1,800 feet (450 to 540 m.) and is a 



