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Sandstones of the Bullhead group cap the summit of Mount Hage, and
large blocks cover the higher slopes of this mountain.

West of Minaker River, the outcrop of the Bullhead forms a narrow
band or rim around an anticlinal ridge. Hage notes that on “a tributary
stream of Minaker River . . . the base of the group is marked by a 3-inch
conglomerate bed composed of pebbles of quartzite, chert, porphyry, and
vitreous quartz, and is overlain by a 12-inch bed of coarse, sugary, quartz
sand and dark grey, coarse- to medium-grained, quartzitic sandstone.
Only the basal part of the formation is exposed in the area, and the total
thickness of the group there is believed to be less than on Sikanni Chief
River’.

Somewhere between Pocketknife and Tetsa Rivers, the Bullhead group
disappears from the geological column, for it has not been found in Tetsa
and Liard Valleys.

Sufficient study has not yet been made of the Bullhead group between
Halfway and Pocketknife Rivers to establish its origin definitely. Coal
seams suggest non-marine deposition of at least a part of the group.

Age and Correlation
(See Figure 12)

The sandstones and shales of the Bullhead group, as now defined, were
correlated by Dawson (1881) with the Dunvegan formation. Referring to
the lower sandstones and shales, to which he gave the formational name of
Dunvegan, Dawson stated that they “may further, I believe, be regarded as
probably including the sandstones of the Canon of the Mountain of Rocks
above Hudson’s Hope’. Galloway (1913) placed the sandstones and
shales exposed in the Peace River Canyon, or Canyon of the Mountain of
Rocks, in the Dunvegan formation, following Dawson. Six years later
McLearn (1918) showed that these sandstones and shales were older than
the Dunvegan, and a new formation was proposed for them, to which the
name of Bullhead Mountain was given. As already noted, it was divided
into two members. No fossils were at that time found in the lower member,
but ‘‘a few cycads, conifers, etc., and a single specimen of a dicotyledon”
were collected from the upper member. It was noted that “the plant
association of this flora suggests that of the lower part of the Blairmore
formation of the Crowsnest district’? (McLearn, 1918). The entire for-
mation was placed in the Lower Cretaceous. The flora collected from the
upper member was later examined by E. W. Berry and correlated by him
with the Kootenay of the southern Foothills (See McLearn, 1921). The
dicotyledon was lost, and did not appear in the collection submitted to
Professor Berry; moreover, he was at that time unacquainted with the
floras of the Blairmore formation. Later, Berry (1926) revised his cor-
relation of 1921 and compared the flora of the upper member, by that time
named Gething, with the flora of the lower part of the Blairmore formation
of the southern Foothills. This lower Blairmore flora, found in 1916 by
McLearn in the lower part of the Blairmore formation in southwestern
Alberta, was dated “uppermost Comanchean” — using Comanchean in the
sense of Lower Cretaceous — by McLearn (1916); “later part of Aptian
time and all of Albian time”, by Berry (1929); “about Aptian”, by
McLearn (1929); and “as old as Aptian” by McLearn (1932). For many

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