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detected in the air photographs. Exploring prospectors have reported
that in travelling eastward into the mountains from the Rocky Mountain
Trench, no evidence of glaciation could be seen on some of the higher
levels, and the ice from the trench appeared to have pushed eastward
up some of the valleys.”

Williams (1944) makes the following comments on glaciation in the
vicinity of Summit Lake on the pass between the drainage to Toad and to
Fort Nelson Rivers. Summit Lake is the highest point on the Alaska
Highway (altitude, 4,253 feet).

“The grey limestone mountains of the pass are similar in appearance
to those at Jasper, but the valley itself is much narrower. Peaks to the
north and south rise to heights of about 7,000 feet. A main peak to the
north is named ‘St. Paul’ on the map and its companion of the south ‘St.
George’. Other peaks are nameless. About 15 to 20 miles south by east
from the Highway, a group of peaks rises to conspicuous heights, and one
of the mountains supports a hanging glacier. This is the highest group
seen in the front range, some of the peaks probably rising to 9,000 feet
above sea-level.

“Along the pass the peaks have rounded crests and are joined by long,
gentle ridges. A peak south of mile 105 has conspicuous cirques on its
west and north sides, and a terminal moraine occurs where the west facing
glacier joined the ice-stream feeding north into MacDonald Creek Valley.

“Pronounced terraces of glacial till flank the sides of the pass to an
elevation of about 700 feet above Summit Lake. These terraces may be
traced for some miles to the east along Tetsa River and for some 20 miles
to the northwest down MacDona’d Creek. North of Summit Lake, local
erosion has left well developed ‘Hoodoos’ of till standing on the mountain
side. Similar terraces occur along Muncho Lake, and up a side valley
hoodoos are present and others are being formed.”

The glacial deposits that occur along the route of the Alaska Highway
between Fort St. John and Fort Nelson have been described by C. O. Hage
(1944) as follows:

“Deposits of glacial material of various types occur along almost the
entire route of the Highway from Fort St. John to Fort Nelson. On the
higher land the deposits are thin to absent, whereas on the lower slopes,
especially in the valley bottoms, the deposits are thick. Glacial lake clays
are found in most of the larger stream valleys, and boulder clay having the
nature of ground moraine is the characteristic deposit elsewhere.

“Bedded clay deposits up to 50 fect thick are found in Beatton, Half-
way, Minaker, and Prophet River Valleys. In most instances they are
underlain and overlain by till. The underlying till differs from the over-
lying one in the composition of the contained pebbles. Along Halfway
River, about 3 miles east of Pink Mountain, and along Minaker River
north of mile 155, the underlying till contains pebbles of quartzite and
sandstone. On a tributary stream flowing into the Minaker from the
west a 20-foot gravel deposit underlies the glacial clay. The gravel is
composed of well-rounded pebbles of sandstone of various kinds and of
chert, limestone, light grey quartzite, and feldspar porphyry. Similar