Landforms of British Columbia 1976 - Department of Geography

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The Front Range structures consist of a succession of overthrust sheets lying
between southwesterly dipping faults which slice the great limestone formations of
the Upper Devonian and Carboniferous into a number of blocks. Erosion of these
geologically complex blocks has produced the numerous parallel ranges which con-
stitute the Front Ranges, each range being composed mostly of thick southwesterly
dipping limestones. The resistant limestone forms 30. to 45-degree dip slopes
facing southwest, and steep scarp slopes facing northeast. Late Pleistocene cirqw
glaciation has accentuated the sharpness of the topography of the east- and
northeast-facing scarps, The Front Ranges ,form striking mountain units that rise
abruptly above broad glaciated longitudinal valleys which separate them.
In the south many of the valleys separating individual ranges arc underlain
by soft, more easily eroded sandy and shaly rocks of Jurassic and Cretaceous age.
These low areas of Mesozoic rock for the most part are too small to be separately
designated. However, west of Erickson Ridge and Taylor Range and east of the
range flanking the west side of the Elk River there is a structural basin in which
Jurassic and Cretaceous rocks occur, This is the Fernic Basin (see? Plate XXXIVA),
which has a length of 65 miles and a maximum width of 15 miles near the south
end. The east and west boundaries of the Fernie Basin are fault-controlled.
North of the railway bend at Natal the Fernie Basin is very largely the valley
of the Elk River with flanking ridges such as Natal Ridge (7,000 feet) and Fording
Mountain (6,000 feet) along the eastern side. South of Natal the basin widens,
and elevations of 7,000 feet are reached on Fernie Ridge and east of the head of
Coal Creek. There the rocks lie in a gentle open syncline. The gently sloping
uplands at elevations above 5,000 feet are being incised by tributaries of the Elk
River, Michel and Morissey Creeks, and the Flathead River. The general aspect
of the Fernie Basin is one of moderate relief, in which gently sloping uplands
descend by more abrupt lower slopes to the levels of the Elk and Flathead Rivers
and their tributaries.
[References: Leech, G. B., “ Geoloa, Fernie (West Half),” Geol. ,Surv.,
Canada, Map 11-1960; Price, R. A,, “ Fernie Map-area~(East Half) ,” G&. Surv,,
Canada, Paper 61-24.1
[Photographs: B.C. 891:73; R.C.A.F. T3lR:l75; R.C.A.F. T3lL:l64,
167, 174, 184, 196.1
The ~o&wa~~ (~&ern~ Ranges of the Rocky Mountains (see Plate XXXIVn)
lie between the Rocky Mountain Trench and the Kootenay-White River lineament.
From the mouth of the Kicking Horse River to the Bull River the length of these
ranges is 140 miles and their maximum width is 18 miles. The Kootenay (Western)
Ranges include the Brisco, Stanford, and Hughes Ranges, The ranges are.
characterized by geologic structures of very great complexity, unlike structures
known elsewhere in the Canadian Rockies.
The Stanford Range is described as being representative of the ranges at
large. The Stanford Range is dominated by a number of northwestefly trending,
almost parallel structural ridges, These are deeply incised and partly dissected by
transverse valleys which contain trunk streams or tributaries to streams that occupy
the longitudinal valleys between the ridges. The ridge tops are at elevations
between 5,200 and 8,000 feet and range in character from some that are broad
and rounded to others that are narrow and almost knife-edged.
“Within the range the local relief is from about 2,SOi3 to 4,000 feet, but,
adjacent to the Rocky Mountain trench or Kootenay River valley, the local relief
is commonly about 4,500 feet and may be as much as 6,000 feet, The highest
summit in the Stanford Range, Indianhead Mountain, has an elevation of about
87