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The southeast limb of the Beavercrow Mountain anticline rests on
Beavercrow Mountain, at the northern border of the map-area. Study of
air photographs suggests to Kindle (1944 map) that this structure trends
northeast; that the dips on the southeast limb are from 10 to 30 degrees;
that dips on the northwest limb are from 35 to 85 degrees; and that the
axial plane has a pronounced southeast dip.

Kindle (1944) has recorded a major anticline, the West Grayling anti-
cline, 27 miles northwest of the mouth of Grayling River and extending from
Grayling River to and beyond Crow River and to 1 mile or 2 miles west of
Larsen Lake. It lies partly on and partly north of the map-area and trends
northerly. The low-dipping, resistant rocks of the east limb underlie a
high plateau between Crow and Grayling Rivers. The beds of the west
limb appear to dip from 25 to 85 degrees west.

Southeast of the above structure is the symmetric East Grayling anti-
cline, trending south for 12 miles between Scatter and Grayling Rivers.
Kindle (1944) has observed that the strata on both limbs of this fold dip
about 10 degrees, near Scatter River. Farther southwest, toward Grayling
River, they steepen and appear to reach, or even exceed, 45 degrees.

La Biche Anticline

The crest of La Biche Range, north of the map-area and west of
Kotaneelee River, is the crest of an anticline that trends northerly, north
of La Biche River, and northeastward, south of that river. Hage (1945)
records a dip of 40 degrees on the east limb and 35 degrees on the west
limb. Mississippian rocks outcrop on the crest and Mississippian, or
Pennsylvanian, and Lower Cretaceous beds on the flanks. This structure
plunges to the southwest, where Cretaceous rocks outcrop along the axis of
the fold. It may pass into the Beaver Creck anticline and possibly into
the Scatter River monocline.

Liard Range Structure

The Liard Range, north of the map-area, occupies the southwestern
part of Northwest Territories. Hage (1945) records the presence of tivo
or more anticlines, the easternmost of which is bounded by a west-dipping
fault. The Pointed Mountain anticline at the southern end of this range
trends north 30 degrees east and plunges to the southwest (Hage, 1945).

Petitot River Syncline

The Petitot River syncline, north of the map-area, is separated from
the Liard syncline by a thrust fault near Fort Liard. It trends northward
and crosses Petitot River about 20 miles above its mouth. Hage states that
the Liard thrust passes into a fold farther south (Hage, 1945).

ROCKY MOUNTAINS
PINE RIVER TO MUSKWA RIVER

In 1881, Dawson stated that the attitude of the rocks on some of the
mountains in Pine River Valley is nearly flat. He also noted that strata,
mostly limestones, in mountains west of the Upper Fork of Pine River have
chiefly southwesterly dips. Beds on the eastern border of the ‘limestone

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