Figure 9. Trough crossbedding in Vic Sandstone
member of the Midas Formation. (GSC 191005)

The Vic Sandstone can be found as far north as the
junction of Antler and Pleasant Valley creeks where it
is approximately 10 m thick and was mapped as Yanks
Peak Formation by Campbell et al. (1973). There it shows
very little crossbedding but is graded in much the same
way as at the reference locality. As Sutherland Brown
(1957, p. 27) reported, the Vic Sandstone member can
be traced southeastward some 10 km. Approximately 8 m
of Vic Sandstone are exposed on the northeast-trending
ridge from Middle Mountain. South of Cariboo River,
4m or less, approximately 20 m from the top of the Midas
Formation and 25 m from the base, are found in the sec-
tion 5 km southeast of Black Stuart Mountain. The Vic
is also found in the section on the southern slope of
Kimball Ridge where it is 8 m thick and occurs 70 m above
the base and 60 m from the top of the Midas Formation.
Large scale crossbedded fine quartzites are also found on
Anderson Ridge and also beneath the dark grey to black
phyllite and siltite reported in the section 4.5 km southeast
of Black Stuart Mountain.

Several sections of Midas Formation from south of
Cariboo River are described below. They are presented
to give an indication of Midas Formation stratigraphy
in this area. Two of these sections have been described
by Mansy (1970), but these descriptions differ somewhat
from his interpretation. The section 5 km southeast of
Black Stuart Mountain is different because the strati-
graphy and structure of this area have been considerably
changed from that of Mansy. His interpretation of the
overlying Mural Formation is agreed upon and is now
supported by fossil evidence, however, the lower part of
the section involves a transition through Yankee Belle
Formation which is thrust onto Yanks Peak Formation.
Mansy (1970, p. 49-50) provided mineral compositions
for quartzites of his sections.

The Midas Formation section 5 km southeast of Black
Stuart Mountain (52°51’40’’N, 121°05’W) provides a
good reference locality (Table 7).

Table 7.

Midas Formation stratigraphic section

5 km southeast of Black Stuart Mountain

(location, 52°51’40”N, 121°05’W).

Unit

Thickness in metres

Lithology Unit

Above base

wo

lo)

~S

[op)

on

=

w

PO

—

Base of Mural Formation light grey
moderate to finely crystalline
limestone.

Covered-probably green phyllite
with minor limestone in 1 cm thick
lenses

Interbedded quartzite, grey green,
fine grained, and slate, green grey
Bana Grey QHEONE eeih. yin. sell ees 3.9

Quartzite, pinkish weathering-
greenish grey, fine grained parts in
GH THIGK TAVOTS2e 2S 3 Pes 5

Slate, light brown and green grey,
weathering green grey; grades into
overlying unit

Siltite, grey, minor green grey slate
grades into overlying unit ........ 1

Quartzite, green to light green,
slightly micaceous, fine grained
with coarser fraction near top .... 3.5

Interbedded quartzite, green and

light green, fine grained; slightly
sericitic, 1 cm partings, trough
crossbedding and slate, grey and

green, 40 to 30%, grades into
overlying unit, irregular contact

with underlying unit ............ 4

Slate, green grey, green, moder-

ately dark grey and grey, minor
quartzite, green grey, very fine

grained; ‘SEnehes 2% 2S, GEA ON 6

Phyllitic slate, greenish-grey and
brown weathering dark grey .....

Quartzite, grey, very fine grained;
fine Nameless ten re ee ry a al

Interbedded phyllite, grey, and
quartzite, grey, fine grained ..... 5

Interbedded quartzite, grey green,
fine grained, and phyllite, dark
REG, Sitio: WARN) RIS cis i ne ea 1

Quartzite, dark rusty purple and
pink and green weathering light
pinkish grey, fine grained ....... 35

Yanks Peak Formation

Quartzite, pinkish-light green grey,
medium grained; 30 m lens
C2 | gah apes air in, Sc ella Te

Underlying beds: Yankee Belle
Formation

48.85

43.85

40.35

39.85

33.85

32.85

29.35

.35