Toward the northwest, the upper part of the Dunvegan formation is conglomeratic and the lower part consists of shale and sandstone. Toward the southeast, the upper part consists mainly of massive sandstones and shales, and the lower 100 feet, composed of shales and sandstones, is transitional to the underlying Sikanni formation. At Steamboat Mountain, the formation is 550 feet thick and, although the overlying beds are absent, this may represent the full thickness.

In the lower Sikanni Chief River-upper Fort Nelson River locality, the "shale" member of the Sikanni formation is about 1,260 feet thick and the underlying "sandy" member is 195 feet thick. Neogastroplites cornutus was found in talus from the "sandy" member. The base of the Acanthoceras zone (and the upper part of the Fish Scale zone) lies 760 feet below the top of the Sikanni formation. Near Steamboat Mountain, the Sikanni shale member is about 250 feet thick and the underlying sandstone member, consisting of seven strong sandstones with about four weak sandstones above, is approximately 800 feet thick. The Dunvegan and Sikanni formations were followed by air north-northwestward and found to be the equivalent of the Fort Nelson formation.

A thick shale formation, examined in the valleys of Tetsa and Chischa rivers, is regarded as the equivalent of the Buckinghorse formation--excluding the basal passage beds. It was subdivided into an upper (shale) member 1,345 feet thick, a middle (sandstone, siltstone, and shale) member 232 feet thick, and a lower (shale) member 2,040 feet thick. This formation lies on the Triassic Toad formation

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but no angular discordance was found at the contact. Inoceramus cadottensis was found in talus from the middle member.

The correlation table (Fig. 4) revises the correlation of the Cretaceous beds along the foothills, and easterly to northern Alberta. The lower (sandstone and shale) part of the Scatter formation is correlated with the Gates formation and with the lower part of the Falher member of the Spirit River formation. A lower Gastroplites horizon is used as a basis to correlate the upper (sandstone and shale) part of the Scatter formation with the middle member of the Buckinghorse formation in Chischa River, with part of the Commotion formation in Pine River foothills, and with the Cadotte member of the Peace River formation. An upper Gastroplites horizon is used as a basis to correlate a part of the Lepine formation with a central part of the Hasler formation in East Peace River foothills. Rep esentatives of the Neogastroplites fauna have been reported from the Goodrich formation and Sikanni sandstone member from all localities shown and from the "fissile shale" of the Liard River north of Nelson Forks locality. Because their position in the Shaftesbury formation is considered to be between the Gastroplites and Neogastroplites horizons, and because of the different composition of the Pelican sandstone compared with that of the Sikanni sandstone member, the Pelican formation (containing Placenticeras?) and the Joli Fou formation are correlated with the Placenticeras liardense zone and the underlying shale in the Liard River west of Nelson Forks locality. The Sikanni and Dunvegan formations are correlated with the Fort Nelson formation on the basis of field work and air reconnai sance.

The first known occurrence in northeastern British Columbia of the fossil Halilucites sp. is reported from Triassic beds.