Miles
DESCRIPTIONS .OF FORMATIONS
Palaeozoic

tee Approximately 900 feet of Palaeozoic strata are exposed
along the crest of a tightly folded anticline crossing Sikanni Chief

“River about 2 miles west of Mount Withrow. The strata consist of
light and dark grey limestone interbedded with about an equal amount
of black and light-coloured chert and siliceous limestones Beds
range in thickness from 12 to 18 inches. The chert deposits are
irregular but form continuous beds, and outo#ops have a distinct
banded appearance, Most of the limestoné 148 crystalline, but minor
amounts &fe crinoidal and denses

Fossils are scarce. Those collected were identified by
A. E. Wilson of the Geological Survey as of Lower Mississippian age.
The collection includes the following species: cf. Triplophyllum

—S

The contact with the overlying Mesozoic strata was not
observed, and as the investigations were not carried west of the
anticline the position of the exposed beds with respect to the top
of the Palaeozoic section is not known, but is believed to be very
close to the top.

Schooler Creek Formation

All strata of Triassic age in the area are included in
the Schooler Creek formation. The upper part outerops on Pink
Mountain above Halfway River and at two other localities, 3 and 9
miles respectively north of the river. Several-hundred feet of the
upper part of the formation is exposed on Sikanni Chief River north of
Pink Mountain and along the crest of an anticline about 2g miles
west of Minaker River and north of Pocketknife Creek. Klingzut -
Mountain and other mountains to the west for about 10 miles are
composed of Triassic strata, Mount Withrow for example, which lies
north of Sikanni Chief River, exposes more than 2,000 feet of these
beds. As the base of the formation was not observed, its total
thickness is not known, but is probably at least 2,500 feet in the
vicinity of Sikenni Chief River. ic

The Schooler Creek strata may be subdivided for
descriptive purposes into three large members. The lower member
consists mainly of black shale, interbedded in the upper part with
dark grey limestone. At one locality 200 feet of these black
shales were observed. Their total thickness is not known. The
middle member is composed of argillaceous limestone, calcareous
siltstone, and sandstone interbedded with dark grey to black shale
and sandy shale. It is at least 1,800 feet thick. The upper few
hundred feet is predominantly bedded limestone with minor amounts
of argillaceous limestone and siltstone interbedded with dark grey
to black, hard, bedded shale. The limestone beds contain abundant
fossils, especially pelecypods. All Schooler-Creek beds are believed
to be of marine origin.

Fossils collected from the upper member are predominantly
of Upper Triassic age, whereas the middle and lower members contain
Middle Triassic fossils. The following is based on identifications
by F. He. McLearn of the Geological Survey;