70

Coal seams are found in various parts of the ‘Non-marine Bullhead’,
“but thick seams are most common in the upper part of the coal-measures”’
(Mathews, 1947). Fossil plants include a liverwort, ferns, cycads, and
conifers.

Halfway River to Pocketknife River

Undivided Bullhead Group

The Bullhead group has not been subdivided north of the Peace River
Foothills. Although it must have a wide distribution there, it has only
been examined and mapped in a few places and only studied in detail at one
locality. No record has been made of the nature and distribution of this
group in Graham, Chowade, and Cypress Valleys.

Not much is known of the distribution of the Bullhead on Halfway
River. Massive sandstones are exposed on a high ridge on the north side of
the river about 5 or 6 miles west of the mouth of Quarter Creek. Sand-
stones, thin-bedded siltstones, and grey and black, carbonaceous shale, with
fossil plant fragments, outcrop in the lower part of Grave Creek. Thick
sandstone ledges also appear on the west side of this valley and extend up on
a high hill where the rocks are folded into an anticline and syncline. The
basal sandstones of the Bullhead group are exposed also on the west slope
of Mount Wright.

The Bullhead outcrops on Pink Mountain, where it occupies most of
the top of the hill and all of the flanks. It has been described by Hage
(1944). At the base is a coal seam, more than 5 feet thick, which is ‘‘over-
lain by 140 feet of fine-grained, dark grey sandstone interbedded with dark
grey and carbonaceous shale”. Hage notes that these “beds resemble the
Kootenay formation in the Foothills of southern Alberta, and are overlain
by coarse-grained, quartzitic sandstone beds with conglomerate and scat-
tered pebbles of chert, quartzite, limestone, altered ironstone, and por-
phyry in the basal part. Minor amounts of dark grey, carbonaceous shale
are interbedded with the sandstone”’.

The Bullhead is exposed in two good sections on Sikanni Chief River,
both of which are north of Pink Mountain. It is also present at the upper
waterfalls and on the top of Mount Hage. One of the two good sections has
been studied in detail by Hage (1944). It extends from near the mouth of
Chicken Creek upstream for about a mile. This section comprises 835 feet
of Bullhead strata, consisting of beds of sandstone 0:8 foot to 46 feet thick,
and beds of shale 0-5 foot to 9 feet thick, but including much more sand-
stone than shale. The sandstones are light to dark grey, are mostly fine
grained, and are either massive or bedded. Some layers are ripple-marked.
The sandstones are in part hard and quartzitic, and conglomeratic types,
that is, sandstones with layers or lenses of conglomerate, appear in parts
of the section. Thin coal seams range throughout the exposed parts.
Hage suggests that the basal sandstones and shales of the section on Pink
Mountain are missing on Sikanni Chief River, but notes that the lowest bed
of this Sikanni Chief section is “within 200 feet of the base of the group”,
implying that the basal beds are concealed and not included in the measured
section. Farther west, at the upper falls on this river, the Bullhead is
pee ie thick (Hage, 1944), indicating an increase in thickness from east

0 west.