78

in a new formation to which Wickenden and Shaw (1943) gave the name of
Commotion.

On the north side of Pine River Valley this formation is exposed
between Fred Nelson and Crassier Creeks, on Alvin Creek, and on the
lower part of Commotion Creek. On the south side of the valley it out-
crops on Falls Mountain, in a long, narrow band from nearly opposite the
mouth of Fred Nelson Creek to Hasler Creek and east of the mouth of
Goodrich Creek.

Wickenden and Shaw (1943) state that no complete exposures of the
Commotion formation are known. However, they measured a part of the
formation as exposed on Hasler Creek, and the section, in descending order,
is as follows:

Thickness
Feet
(Approximate)
@hent-pebbleiconglomerateyeaace eer ee eee eee eee 100
Sandstonere sss ae rere sa eee ees aoa He nae ee eee 200
Darkjereyishales re aa cece era ee enone 250
ANGSCONS SE : epysers Raye aieseatt sea cP Aen is aarti aE ices SPACER eth eee eee 500-600

Base of section concealed

They also note that 180 feet of sandstone, shale, and coal overlie con-
glomerate on Commotion Creck, and observed two bands of conglomerate
near Goodrich Creek. They collected some marine fossils: Inoceramus cf.
altifluminis, from about 145 feet below the conglomerate on the west bank
of Commotion Creek about 500 feet below the falls; and species of marine
pelecypods from shale below the conglomerate on Hasler Creek, about 4
mile below the coal mine (See Figure 13). Stelck (1941) has reported
Gastroplites from the upper part of the formation. Fossil plant fragments
have been found in beds above the conglomerate on Commotion Creek.

Wickenden and Shaw estimate that the thickness of the Commotion
formation in Pine River Valley is at least 1,300 to 1,500 feet, depending
“on where the contact with the Moosebar is placed’’.

Farther west, between Pine and Peace River Valleys, southeast of
Mount McAllister, Mathews (1947) has mapped an area of steeply dipping
conglomerate as the Commotion formation. He has also mapped sand-
stones of this formation near Carbon (Indian) Lake. Mathews describes
an exposure of the lower part of the formation ‘‘on the south fork of Gething
Creek, 3 miles northeast of Mount McAllister... Here the formation
possesses a gradational contact with the underlying shales and consists
ey a sandstones, in part ripple-marked, and at least one thin conglomer-
ate bed’’.

The coal seams and plant remains record a non-marine origin for some
of the upper layers of the Commotion formation. Marine shells, however,
indicate that a large part of the formation is of marine origin.

Hasler Formation

The Hasler formation lies between the Commotion and Goodrich
formations in Pine River Valley, where it consists of 1,100 to 1,200 feet of
shale, with, here and there, thin beds of siltstones and fine sandstone, and
in at least one place a band of conglomeratic sandstone has been observed.
In Peace River Valley it lies between the Gates and Goodrich formations,
and, consequently, includes lower beds than on Pine River.