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the adjoining ones. These are: the Queen Charlotte range, the
Central Plateau province, the Northeastern lowlands, and the
Northern lowland. These topographical divisions will be
described separately. Their boundaries are shown in Figure 1.

The Queen Charlotte range (Plates I, I, and III) forms the
mountainous western portion of the island. These mountains
consist of a series of pre-Cretaceous metamorphic and volcanic
rocks, with small areas of intrusive plutonic rocks and perhaps
occasional basins of Cretaceous sediments, together with over-
lying Tertiary volcanics. This complex is carved into rugged
peaks and ridges, in many places serrate, though not as a rule
needle-like, and with many very steep, precipitous slopes. Many
of the slopes and some of the summits are glaciated, but glaciation
does not appear to have been extensive above the 3,000-foot
level. A distinctive feature of the range is the cuesta-shaped
peaks, especially prominent in the northern portion, and caused
by gently northwestward dipping sheets of Tertiary volcanic
rocks. The range is partly cut across by several of the west
coast fiords, also by the valleys of Yakoun lake, Rockoun river,
Hidden creek, Ghost river, King creek, and other creeks and
rivers. The range becomes lower in the northern portion where
its height probably does not exceed 2,000 feet, and nowhere on
Graham island is the elevation greater than 3,500 feet.

Fringing the Queen Charlotte range, and lying between the
mountains and the Northeastern lowland, is the second topo-
graphic division, termed the Central Plateau province. Starting
at the mouth of Slatechuck creek at Skidegate inlet, the boundary
between the mountains and the Plateau province swings north-
eastward and northward around the eastern flanks of the Slate-
chuck range, of which Slatechuck mountain is the highest point,
and continues in a general northerly direction to the middle of
township 8. Near this point the boundary between the Central
Plateau province and the northeastern lowlands meets the
Queen Charlotte range. This boundary runs east to the eastern
part of township 7, whence it turns sharply southeast, reaching
the east coast of the island midway between Dead Tree point
and Skidegate Indian village.