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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”.