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than 4 feet thick, are present.” Marine shells were collected. Plant
fragments, “but no other fossils of continental origin were seen. The
formation is probably marine’.

Monach Formation

The Monach formation, established by Mathews (1947), contains
marine, massive sandstones lying between the dominant shales of the
Beattie Peaks below and the non-marine Bullhead group above. It is well
exposed on The Monach and on Beattie Peaks, and extends around the
border of the Carbon Creek basin and south to Beaudette Creek. It is
from 300 to 400 feet thick.

“The Monach formation consists of several thick sandstone members,
each separated by a few feet of shaly beds. Much of the sandstone occurs
in coarse crossbedded layers which weather into stacks of plates, each about
one half to 1 inch in thickness and 1 foot or more across.” The Monach
rests conformably on the underlying Beattie Peaks formation. Marine
shells have been found in it by Mathews, who includes it in his marine
Bullhead.

Non-marine Bullhead

The upper and non-marine part of the Bullhead group, overlying the
marine Monach formation in the Carbon Creek-Mount Bickford map-area,
is not subdivided by Mathews, but is left in one unit, called ‘Non-marine
Bullhead’ or ‘Coal Measures’. It is approximately equivalent to, but is
thicker than, the upper and conglomeratic, coal-bearing part of the Dunlevy
plus all of the Gething of the eastern section of the Bullhead. Mathews
records a thickness of 4,000 to 4,500 fect. It underlies a large area in
Carbon Creek Valley and a smaller area in VWisher Creek Valley. It also
outcrops on Beaudette Creek and east of Falling Creek.

The ‘Non-marine Bullhead’ consists principally of alternating beds of
sandstone and shale, ranging from a few feet to 30 feet in thickness. Some
sandstones and siltstones have symmetrical ripple-marks. Carbonaceous
shales are recorded, and conglomerate occurs with sandstone in thick zones.
A 20-foot bed of conglomerate was observed “‘at the base of the coal-
measures on the Beattie Peaks and 2 miles west of Mount Monteith, but is
elsewhere apparently absent .... Massive sandstone and conglomerate,
30 feet in thickness occur about 1,100 feet above the base of the coal-
measures on Mount Bickford”. Mathews also records that a “Jenticular
conglomerate zone, 20 to 50 feet thick, possibly 1,500 feet above the base of
the coal-measures, marks a distinct erosional unconformity”... at “two
localities on the hill 4 miles west of Mount Monteith; at one locality it rests
upon beds about 30 feet stratigraphically higher than at the second locality
100 yards away. Fossils below this unconformity, however, are similar in
age to those at higher horizons in the coal-measures”. A thick sandstone
member, 55 feet thick, includes some conglomerate and outcrops “near the
mouth of Ten (10 Mile) Creek and at least 3,500 feet above the base of the
non-marine beds . . . Conglomeratic bands, one about 8 feet thick and
another about 25 feet thick, outcrop on Eleven (11 Mile) Creek between
3,500 and 4,500 feet above the base of the continental beds”.