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deposits were subsequently uplifted, presumably during 

 Pliocene times, and were then dissected during a pre- 

 Glacial cycle, initiated by the uplift. Over the larger part 

 of the island, the dissection, which was presumably accom- 

 plished by revived, large, transverse streams with sub- 

 sequent tributaries, reached a stage of maturity, and the 

 Tertiary peneplain and subdued surface is still preserved 

 in the wide, relatively smooth interstream areas. The 

 present elevation of the uplifted Tertiary peneplain is 

 less than 1 ,500 feet (450 . m.) near the southern coast, but 

 increases rapidly to the northwest, so that in the central 

 part of the island, the elevation of the uplifted subdued 

 surface is about 4,000 feet (1200 m.), while the old residuals 

 are now since uplift, 5000 to 7,000 feet (1,500 to 2,100 m.) 

 above sea level, a few peaks being even higher. 



In the southeastern portion of the island, although the 

 region is largely underlain by crystalline rocks of the same 

 character as the rest of the island, the dissection was carried 

 to a further stage, that of late maturity to old age, so that 

 the Tertiary peneplain was entirely destroyed and another 

 subdued surface was developed several hundred feet lower, 

 now averaging about 100 feet (30 m.) above sea level, 

 but surmounted by numerous relatively small monadnocks. 

 The sedimentary rocks along the coasts, the Nanaimo series 

 along the east coast and the Sooke and Carmanah forma- 

 tions along the west coast, being less resistant than the 

 crystalline rocks which form the larger part of the island, 

 were also, reduced during the pre-Glacial cycle to a low- 

 land, exposing the mountainous slope against which the 

 Sooke and Carmanah formations were deposited. These 

 latter formations were, after further uplift, also retro- 

 graded so that now mere remnants of the former Tertiary 

 coastal plain exist, fringing the southern and western coast 

 of the island. It seems as if at some time following the 

 mature dissection of the uplifted Tertiary peneplain and 

 the development of the lowlands, the southeastern por- 

 tion of the island was depressed in part below sea-level, 

 drowning the valleys, but leaving the higher elevations 

 as islands and promontories, and thus forming the irregular 

 drowned coast characteristic of that part of the island. 



In Pleistocene times, Vancouver island was apparently 

 smothered by a thick ice-cap, which smoothed and rounded 

 all the mountains under 4,000 or 5,000 feet (1,200 to 1,500 

 m.) high, while the pre-Glacial valley heads in the higher 



