Chapter II
PHYSICAL FEATURES
Physiography

Two main physiographic subdivisions of the Canadian Cordillera,
namely, the Pacific Ranges of the Coast Mountains and the Nechako Plateau,
are represented in Whitesail Lake map-area. The transition zone between
these two main subdivisions is also well represented.

The rugged granitic mountains at the heads of the long lakes and the
mountains bordering the Kimsquit River valley form the eastern edge of
the Coast Mountains. On the other hand the rolling country along the
eastern border of the map-area is well within the Nechako Plateau region.
The intervening part, including the large lakes, comprises the transition zone
between the two main subdivisions. This lake system is one of the few of
its kind along the whole eastern boundary of the Coast Mountains and is
very similar to the long narrow fiords on the western side.

Coast Mountains

Southwest of the heads of the large lakes, the Pacific Ranges of the
Coast Mountains rise in a series of sharp crested ridges and lofty peaks
separated by a network of deeply incised valleys. Relief at Ear Lake
immediately west of the divide is between 5,000 and 5,500 feet, whereas
relief on the eastern slope of this line of hills is 3,000 to 3,500 feet. Except
for Tsaydaychuz Peak 9,085 feet and Salient Mountain 7,981 feet, the peaks
near the heads of the lakes are mostly about 7,000 feet being slightly higher
in the southern part of the area and slightly lower towards the northwest
(see Plate II B). These peaks form the divide between coast drainage and
drainage eastward through Nechako River to Fraser. River and through
Morice River to Skeena River. They are composed largely of granitoid
rocks particularly on their western slopes but contain significant amounts of
metamorphosed sedimentary and volcanic rocks.

For at least half of their extent in the map-area this line of mountains
is bounded on the west by the deeply incised valley of Kimsquit River
almost 2,000 feet lower than the valley floors on the opposite or eastern
slope of the divide. This valley trends northwest and is longitudinal with
respect to the Coast Mountains. West and southwest of Kimsquit Valley

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