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few miles below the mouth of Cache creek to within about 4 miles of North Pine
river. Overlying this and appearing within about 2 miles of the river are black,
paper-thin shales without fossils. Above this again come dark, thin-bedded,
arenaceous Shales with several large sandstone lenses. Downstream and higher
are thin-bedded sandstone and shale to the contact with the Dunvegan sandstone.
Farther downstream there is much lateral replacement of sandstone and shale
along this contact. The thin, even bedding and marine fossils point to marine
conditions of deposition. The upper shale member is estimated to have a thick-
ness of 1,300 feet in the vicinity of Cache creek.

The small fauna of this formation is correlated with that of the Colorado
group of the Upper Cretaceous.

Dunvegan. Formation: The Dunvegan. sandstone first appears in the
escarpment at Cache creek, above Fort St. John, but a few miles downstream the
higher elevations upholding this formation recede toward Charlie lake. It
reappears in high hills in the north bank a little below the mouth of Kiskatinaw
river. Rapidly descending on the valley sides, it forms cliffs to within a short
distance of river-level. Below Montagneuse river and continuing past Dunvegan
it outcrops to river-level. The formation is made up of light, massive, Cross-
bedded, soft sandstones with large flat concretions, and weathers into castellated
forms. ‘The crossbedding is on a scale of about 2 feet, truncated above, tangential
below. Grains consist of quartz, feldspar, a little mica, and a black mineral.
Other areas of this formation are more argillaceous and locally thin-bedded. A
thin lignite seam in the sandstone varies in thickness but never exceeds 6 inches.
There is also a rather prominent bed of shelly limestone, chiefly of freshwater
shells, in the cliffs below Montagneuse river and below Dunvegan. The cross-
bedded structure, coal beds, and freshwater fossils point largely to subaerial
conditions of deposition, but the presence of Inoceramus and Ostrea indicates
partial brackish water conditions, and probably the sea was not far away at any
time. The formation has a thickness of about 530 feet. Both above and below it
exhibits gradational contacts with continuous formations.

On Smoky river the Dunvegan formation underlies the higher valley sides
and adjacent plateaus from Sixmile point to Racing creek, and the lower valley
sides from Racing creek to Smoky at the railway crossing. Thick zones of
subaerial, concretionary, massive and crossbedded sandstones with beds of
subaerial shale alternate with thick zones of thin-bedded sandstone and shale
which may in large part be of marine origin. The estimated thickness below
Smoky is 440 feet.

The Dunvegan formation is correlated with the Pelican sandstone of Atha-
baska river.

Smoky River Formation. The Smoky River formation succeeds the Dun-
vegan on Smoky river. It underlies the higher valley sides and adjacent plateaus
from about 12 miles below Racing creek to Smoky, the entire valley sides and
adjacent plateaus from Smoky to within about 10 miles of Bad Heart river, and
the lower valley sides from Bad Heart river to within about one mile of Kleskun
creek. The Smoky River formation may be divided on lithological grounds into
three members, a lower shale, a middle sandstone—the Bad Heart sandstone—
and an upper shale. The lower shale and Bad Heart sandstone members are
referred to the Colorado group and the whole or a part of the upper shale member
to the Montana group. The lower shale consists below of paper-thin carbonaceous
shales with concretions; above are dark, friable shales with concretions and at