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information on the general structure of this part of the Interior Plateau.
This section extends from the crest of the Cariboo range for a distance of
55 miles in a southwesterly direction across the Cordilleran trend through
Quesnel Forks to Guy mountain, west of Beaver river. Bowman shows
the main part of this district to be underlain by the Cariboo series in the
attitude of open folds trending northwest. On the northeastern end
of the section they outcrop as the main part of the Cariboo range and are
followed to the southwest by the overlying Bear River beds (Slide Moun-
tain series), which continue approximately to the line of the unconformity
shown on the Barkerville geological map. West of this line, Bowman
shows the Cariboo series again coming to the surface in a broad anticline
whose crest passes through mount Agnes, and continuing to the vicinity
of Cariboo mountain and Keithley creek, beyond which they dip under
the Mesozoic, Quesnel Lake beds.

Two important features which bear on the structure of the Barker-
ville area are brought out by this section: (1) the open character of the
large folds; and (2) the fact that the Bear River beds (Slide Mountain
series) occur in a broad syncline whose southwesterly limb comes to the
surface at the line of the unconformity mentioned above, and whose
northeasterly limb outcrops along the western face of the Cariboo range.
The only major intrusive rock body shown on Bowman’s geological map,
which covers nearly 3,000 square miles, occurs on mount Stevenson, on
Quesnel lake. There is the important fact, therefore, of the general
absence of major intrusives cutting the gold-bearing Cariboo series.

LOCAL

The major structural feature of Barkerville area is a broad, open
anticlinorium, whose axis trends north 55 degrees west from the top of
mount Burdett, through mounts Agnes, Pinkerton, and Amador, to mount
Nelson (See Map 2046). On the northeastern side of the axis the beds
have a general northeasterly dip, varying from a few degrees near the
crest to 70 degrees at a distance of 7 miles from it; whereas on the south-
westerly side the beds have a general southwesterly dip varying from a
few degrees to 35 degrees at a distance of 5 miles. The anticlinorium
pitches a few degrees to the southeast.

Both the Cariboo and Slide Mountain series are involved in this
anticlinal structure. Within the limits of the map-area the Slide Moun-
tain series is exposed only on the northeastern limb. Owing to a covering
of glacial drift and a thick mantle of vegetation it was impossible to ob-
tain sufficient exposures in the southwest corner of the area to interpret
the geology, but at the few available exposures no indication was seen of
rocks of the Slide Mountain series. They may have been removed by
erosion, as the erosion plane dips about 75 feet a mile in that direction.

Folding

The geological structure sections reveal the nature of the anticlinorium.
The main structure consists of a broad, open fold, controlled by the Barker-
ville limestone formation, the heavily bedded, non-schistose, dark-coloured

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