Landforms of British Columbia 1976 - Department of Geography

Mount Perseus (8,361 feet). The Snowshoe Plateau east of Barkerville is a large
remnant of the uplifted and dissected erosion surface of late Tertiary age.
The area in large part is underlain by closely folded schistose sedimentary rocks
of Proterozoic and Lower Cambrian age containing infolds of volcanic and sedimen-
tary rocks of Carboniferous and Permian age. In part there is a relationship between
topography and the type of underlying bedrock; limestone and quart&e formations
form many of the high peaks.
Pleistocene ice covered most of the high areas and consequently most summits
are rounded, but cirques which developed on the northern and northeastern sides
during the late stage. of glaciation have sharpened the profiles of the highest peaks.
Valley glaciers truncated spurs and deposited glacial material over much of the area.
At the southern end of the Quesnel Highland and in the immediately adjoining
areas, there are several volcanic landforms that are clearly visible on aerial photo-
graphs. When the area is more accessible, they will present points of interest for the
venturesome tourist.
There are four or more volcanic vents within a 20~mile radius of the south end
of Clearwater Lake. From a conical vent on the southwest side of Ray Mountain,
lava flowed down Falls Creek for 6 miles or snore, almost to the outlet of Clearwater
Lake. Three vents on Spanish Creek west of the head of Donald Creek poured lava
down Spanish Creek for 6 to 8 miles. Pyramid Mountain (3,590 feet), almost on
the 52nd parallel, is a perfect small cinder cone, The east end of Kostal Lake is
blocked by a small breached cinder cone. All these volcanic features are of such
recent age that subsequent erosion has hardly modified their original forms.
“ The twin peaks of Takomkane Mountain are formed from a cinder cone of
&vine basalt that rests on the glaciated surface of the main mountain mass. The
cone is about 300 feet high, and from it a flow extends about one-half mile to the
northwest. The cone is chiefly built of vesicular cinders and bombs of olivine basalt
as much as 2 feet long by 1 foot in diameter, The mountain had obviously
been glaciated before the cone was built, and the presence of erratic boulders and
minor sculpturing of the cone indicate that it was also glaciated after. All facts indi-
cate that the cone and flows were formed late in the Pleistocene epoch.“*
[References: Map No. ~GL, ” East Central British Columbia,” B.C. Dept. oj
Lands and Forests; Sutherland Brown, A., ” Geology of the Antler Creek Area,”
B.C. Dept. & Mines, Bull. No. 38, 1957; Campbell, R. B., “ Quesnel Lake (West
Half),” Gal. Suw., Canada, Map 3-1961; Campbell, R. B,, “ Quesnel Lake (East
Half),” Geol. Surv., Can&z, Map 42-1961.1
[Photographs: B.C. 482:29, 91; B.C. 487:32; B.C. 765:79.]
Shuwap Highland
The Shuswap Highland (see Plate XXVIIIA) extends southward from Mahood
and Murtle Lakes to the Coldstream Valley east of Vernon, and lies between the
Thompson Plateau on the west and the Monashee Mountains on the east. It is 140
miles long and 50 miles wide. The western boundary of the highland is along a line
from the east end of Canim Lake along Mann Creek to Barriere, and thence to
Vernon along a lineament coinciding with the Louis Creek fault zone. The eastern
boundary is along a line from Blue River down the upper Adams River and across
to the head of Anstey Arm of Shuswap Lake, thence via Three Valley to Mabel Lake
and Shuswap River to Sugar Lake.
The Shuswap Highland consists of gentle or moderate sloping plateau areas
rising from 5,000 to over 7,000 feet, dissected by the Clearwater, North Thompson,
* &tinis,a, 0, M”es, B.C., A”“. rtept., ,95,, L3. 20,
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