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Of the three anticlines studied by McLearn (See Figure 7), the Cameron
Hill and Smith Hill are broad, open, almost symmetrical folds. The Shaw
Hill anticline is narrower, and dips are steeper than on the other two.
Triassic beds outcrop on the anticlines, and the Jurassic or Cretaceous
shales outcrop in narrow bands along the axes of the synclines.

Palzozoic Fault Block

West of mile 381, Alaska Highway, Upper Paleozoic rocks have a
nearly vertical attitude and are in faulted contact with Triassic strata. At
the western end of this fault block, Upper Palzeozoic beds are folded and
in faulted contact with beds of the western Triassic belt (Williams, 1944).
This fault block is also recorded in Laudon and Chronic’s (1949) structure-
section, but dips are lower than shown by Williams.

Western Triassic Belt

In the eastern part of the western Triassic belt “black limestones
and limy sandstones .. . have dominant westerly dips varying from 30 to
68 degrees” and are part of the east limb of a syncline (Williams, 1944).
Farther west, shales and dark sandy limestones dip easterly at angles of
from 13 to 48 degrees, but “the structure is locally confused by crushing,
as indicated by vertical and reversed dips”. Williams states that near the
Rocky Mountain front black shale with some hard chert and quartzose
beds has an average dip of 40 to 50 degrees northeast; crumpling and
reversed dips were noted by him.

On Laudon and Chronic’s (1949) structure profile, the dips are lower,
and the folds broader and more open than on Williams’ structure-section.

FOOTHILLS AND LIARD PLATEAU
LIARD RIVER BASIN

In the basin of Liard River, the structures of the Foothills of the
Rocky Mountains continue into the Liard Plateau; some continue without
change; others disappear and new structures appear. In this passage from
the one structural region to the other, the trend changes from northwest to
north and northeast. The structure of this drainage basin has been studied
by Kindle (1944).

Liard Syncline

The Liard syncline, a major structural feature, has been traced along
its axis for more than 60 miles from the Foothills of the Rockies to the
Mackenzie Mountains. At its southern end, where it crosses Dunedin
Creek, it trends northwest; dips on the northeast limb are 2 to 3 degrees,
and on the southwest limb generally from 10 to 30 degrees. The latter
limb is marked on the surface by a high escarpment of the Lower Cretaceous
Scatter and Lépine formations and the Upper Cretaceous Fort Nelson
formation. The centre or trough of the syncline is occupied by the Upper
Cretaceous Kotaneelee formation. On the northeast limb is a wide outcrop
of aN Fort Nelson formation extending along Fort Nelson River (Kindle,

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