a

These rocks.-have been correlated with the Cache
Creek group of southern Eritish Columbia on the basis of
lithology and stratigraphy. The Cache Creek group was
named by Selwyn! from its typical occurrence in the vicinity
1
Geol. Surv., Canada, Rept. of Prog. 1871-72, pp. 60-62 (1873).

of Cache Creek, near Ashcroft. Dawson® later defined the
Cache Creek group as follows: "The Cache Creek formation

Pe
Geol.’ Surv., Canada, Ann. Rept., vol. VII, 1894, pt. B,
pps 39-40.

includes a very thick series of Palaeozoic rocks, of which

the greater part is definitely referable to the Carboniferous
period by means of fossils. Massive limestones, cherty
quartzites, argillites, and volcanic products are characteristic
of the series". More recent work by Dunbar’ and by Crockford
and Warren* on fossils collected from the group near Cache

aS PET Sh cas
Trans. Roy. Soc.e, Canada, sec. IV, 1932, pp. 45-59.
4 ; ft

Trans. Roy. Soc.,.CGanada, sec. IV, 1925, pp. 150-151.

rn
‘Creck indicate that it is in part of Permian age.

6

In 1875, Selwyn’, and, in 1876, Dawson° visited Stuart

Geol. Surv., Canada, Rept. of Prog. 1875-76, p. 78 (1877).
Ho 3 }
Geol. Surv., Canada, Rept. of Prog. 1876-77, p. 55. (1878).
: a -
Lake, which lies within the Fort Fraser (east half) map-area
joining the Manson Creek area to the south. They correlated
the limestones outcropping on the shore of Stuart Lake with
the Cache Creek group. Dawson collected fusulinee of
supposedly Carboniferous age from them. A re-examination ef
these fossils has shown that they are of Permian age. In 1941
Armstrong’ collected Lower and Middle Permian and probable

7
Geol. Surv., Canada, Paper 42-11, p- 3 (1942).

PSR EDAD a Uo OTOP SS RISO a eT

Pennsylvanian foraminifera. from this limestone series. The
Cache Creek group may, consequently, now be re-defined as:

a very thick assemblage of interbedded sedimentary and volcanic
rocks, mainly of Permian age, but also probably in part of
Pennsylvanian age. Limestones containing foraminifera are
characteristic of the group. i

Wo diagnostic fossils were collected from the Cache
Creek group in the Manson Creek map-area. Lithostrotion of
possible Carboniferous or Permian age was found in limestone