100

(early Upper Cretaceous) age. The equivalent beds, possibly, are to be
found in some very low part of the Blackstone formation.

Correlation with the early Coloradoan of the United States interior has
been proposed in a previous paragraph. The No. 1 zone of Coalville,
Utah; the coal-bearing beds of Kannara and Cedar City, Utah; the Wood-
bine of Texas; and the Bear River formation of Texas are possible cor-
relatives. It is interesting to note that the beds of definite Cenomanian
age, with the diagnostic genus Acanthoceras, have been found in the United
States interior, in the Graneros shale of south-central Colorado, and in the
so-called Dakota of mid-western Colorado (Reeside, 1927).

FORT NELSON FORMATION
Definition

The Fort Nelson formation consists of more than 600 feet of massive,
thick-bedded conglomerate and sandstone, and some shale beds. The
name was first used by Kindle (1944), and applied to beds in the valleys of
Liard River and of streams tributary to it. The type locality is along the
east side of Liard River Valley, from near the mouth of Toad River almost
to the mouth of the Beaver.

Tetsa River Valley

The massive conglomerate and sandstone capping Tepee, Steamboat,
and Table Mountains, east of Mill Creek, are described by Williams (1944)
and referred to the Fort Nelson formation:

“On Table Mountain, the heavy conglomerate series is 550 feet thick.
The conglomerates rest on soft clay shale interbedded with soft sandstone
with a bed of coal 1 foot thick near the top. The slumping and weathering
of this formation have caused the recession of the plateaux, marked by the
cliff fronts and the cones and piles of huge conglomerate blocks that occur
at intervals from Table to Steamboat Mountains. Glacial moraines are
interlocked with these boulder piles, showing that glacial ice has played an
important rdle in the removal of surplus debris and in arranging what
remains.

“On the top of Table Mountain, near the eastern face, one huge cubic
block of conglomerate appears to rest on one corner, forming a landmark
visible from the Highway near Mill Creek.

“The surface of Table Mountain conforms to the surface of the con-
glomerate, which dips about 6 degrees north by east. The conglomerate is
cut into huge joint blocks, which, near the western precipice, have opened
widely, leaving trenches 8 to 10 feet deep and 10 to 15 feet wide.

“The conglomerate on Tepee Mountain includes pebbles up to 2 inches
in diameter. These consist of black chert, bleached yellow chert, white
sugary quartzite, and opaque white quartz. One pebble of coarse-grained
granodiorite was seen. Upward in the formation sandstone occurs.

“The upper 500 to 600 feet of Steamboat Mountain is composed of
massive sandstone and conglomerate. The basal beds are of hard, cream
weathering sandstone, 50 feet thick, and the upper beds consist of massive
conglomerate. The formation is cliff-forming, as may be seen in the east
face of Steamboat Mountain. The upper massive conglomerate overhangs
as much as 50 feet and the precipice is over 500 feet high.