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The Sans Sault formation in Mackenzie River Valley contains fossils
of marine origin, including the diagnostic ammonoid genera Gastroplites and
Lemuroceras (Link and Hume, 1945; Warren, 1947). It is correlated with
the lower part of the Fort St. John group in Peace River Valley—that is,
with the Moosebar, Gates, and Hasler formations.

The Haida formation in the Queen Charlotte Islands is like the Fort
St. John group of Albian age, although its exact age within the Albian has
not yet been established. The faunas, however, have nothing in common.

Gastroplites has recently been discovered on Sabine Island, East Green-
land (Spath, 1946), in “‘clay-ironstone concretions from the Inoceramus
beds’.

On the island of Madagascar, the ammonoids with which Lemuroceras
is associated are of the mammillatum zone of the Albian stage (Spath, 1942).
In the Gault formation of Folkstone, England, Gastroplites occurs in the
cristatum zone of the Albian stage, and, therefore, is of somewhat later
Albian age than Lemuroceras.

Unfortunately, Neogastroplites has so far only been found in north-
eastern British Columbia, and, therefore, affords no evidence for inter-
continental correlation. It is dated late Albian because it is closely related
to the Albian genus Gastroplites, but the possibility of an early Cenomanian
(early Upper Cretaceous) date cannot be entirely eliminated.

UPPER CRETACEOUS
DUNVEGAN FORMATION
Definition

The Dunvegan formation lies conformably between the Fort St. John
group below and the Smoky group above, and consists of 350 to 1,200 feet
or more of marine and non-marine, light grey, massive, crossbedded sand-
stones, flat ironstone concretions, thick shales, thin-bedded sandstone and
shale, rare calcareous layers, and rare, thin coal seams.

The name was first used by Dawson (1881), and applied to what he
called the ‘Lower Sandstones and Shales’ of Pine and Peace River Valleys.
Among the sections described by him was that exposed in the cliffs on the
north side of Peace River, west of the old Hudson’s Bay Company trading
post at Dunvegan on Peace River; this, presumably, is the type locality.

Pine River Valley

The Dunvegan formation has been mapped in the Mount Hulcross-
Commotion Creek map-area by Wickenden and Shaw (1943). It out-
crops in an area between Huleross and Bowlder Creeks ; in the vicinity of
Cruiser Mountain; and on the south side of Pine River, east of Young
Creek. The formation is more than 1,200 feet thick, and consists mostly
of sandstone, with some conglomerate. “The beds near the base are
usually fine-grained sandstone, and at many localities conglomerate or
conglomeratic sandstone occurs about 100 feet above the base. Cross-
bedding is prevalent throughout most of the formation.” Unio dowlingi
has been collected about 50 feet above the base at localities east and west
of commotion Creek, and fossil plant fragments were found on Cruiser

ountain.

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