~1-

Collection 16A,; from southeast slope of Kloch liountain
at an elevation of 3,200. feet, includes abundant specimens of Neo-
schwagerina. Age: Middle Permian, same as 4A.

Collection 56K, from southeast end of ridge lying between
Pinchi: Village, Stuart Lake, and Pinchi Lake, ineludes & single species
of Triticites. Age: probably Pennsylvanian..

Small, lenticular bodies of greenstone, up to 5 square
miles in area, are intercalated with the Permian sedimentary rocks.
The greenstones are predominantly grey~green to dark green, fine- to
medium-srained, chloritic andesites, amphibolites, dioritic rocks,
and related schists. In places they cut across adjacent Permian
strata; in other places they appear to be interbedded with them. The
greenstones probably comprise sills, flows, and minor intrusions.

The Upper Triassic rocks consist essentially of inter-
bedded argillite, greywacke, and tuff with, here and there, thick
beds of conglomerate and limestone. The argillites are black, car-
bonaceous rocks in beds a fraction of an inch to 6 inches thick. At
the east end of Pinchi Lake they exhibit a good slaty cleavage about
parallel to the stratification. The tuffs and greywackes weather
blue=grey to buff, are fine- to medium-grained, and form beds that
vary from less than an inch to 10 feet in thickness. They consist
largely of fragments of cherty and volcanic rocks, quartz, and feld-
spar in varying proportions. Intermediate types, best termed tuf-
faceous greywackes, are the most widely developed. Many beds grade
from coarse-grained, tuffaceous greywacke at the bottom to argillite
at the top. These rocks also exhibit good crossbedding.

Two beds of conglomerate, each 25 to 50 feet thick,
are.exposed at the east end of Pinehi Lake. Thinner beds outcrop
on Halobia Creek northeast of Indata Lake. Pebbles in the conglomerate
are angular to rounded, and up to 3 inches in diameter. Most are grey
“chert and black argillite, a few are greywacke, limestone, and vol-
canic rocks. The matrix is gritty. A few lens-like beds of grey-
wacke are contained in the conglomerate. NaN

Ais aN Two bands of brownish grey, medium-grained, crystalline
limestone,:at least 150 and 300 fcet thick, outcrop on the two long
points.on the north side and near the east end of Pinchi Lake. The
limestone weathers light buff and is veined by white calcite stringers.
It contains small lenses of conglomeratic material consisting largely
of fragments of cherty and: voleanic rocks... Interbedded with the
limestone is a flow of fine-grained, green andesite. Beds of grey
limestone. 15 to 20 feet thick outcrop at the east end of Pinchi Lake

and along Roddacker Creek. Arann eterna a

- The: minimum thickness of the Upper Triassic section is
estimated at various localities.as follows: =
Feet

Fast énd-of Pinchi Lake; argillite, slate,,
ereywacke, tuff, conglomerate sereerseneseree 400

North shore of Pinchi Lake; “limesttne, argillite,
tuff, greywacke, andesite A OUR eet el eatglaereteiels, 500

Halobia Creek; argillite, ercywacke, tuff, con-
glomerate coveoseeosseerreereosrersaseoneeearaeree 1,000