13

EY The best coal is in the lower part of the seam.
Its rank is medium volatile bituminous.

Six feet above the Knight seam is a 1.2-foot seam,
Eleven feet higher is 0.4 foot of coal overlain by 0.4 foot
of shale and 0.4 foot of coal. Twelve feet higher still is
a 1.2-foot seam. No others were noted between this seam and
the Galloway sandstone. Some beds, however, are concealed in
the shore section. i ¢

The beds between the Galloway and Cust Island sand-
stones contain very little coal. About 0.5-foot of coal is
found 10 feet above the Galloway sandstone and a small vari-
able seam, a little less than 1 foot thick, occurs immediately
below the Cust Istand sandstone. ,

-DUNLEVY GREEK-CUST CREEK AREA
Geology

-.° Only a reconnaissance examination was made of the
territory between Dunlevy and Cust Creeks. Large seams have
been reported, but none was found within a few miles of the
road...

Topographically the area includes the west side of
Butker Ridge and the southern parts of the valleys of Dun-
levy, Gravel Hill, and Cust Creeks,

Butler Ridge is underlain by the Dunlevy formation,
and the lower parts of Dunilevy. and Gravel. Hill Valleys by the
Gething formation, Both formations are exposed in Cust
Valley. The structure includes the steep west limb of a
flat-topped anticline on the west side of Butler Ridge, and
the more gentle slopes of the same limb in Dunlevy and Gravel
Hill Valleys. Dips on Butler Ridge are from 40 to 70 degrees
southwest, and in Dunlevy Valley from 2 to. 5 degrees south-
west. The structure ‘On. AMEN: Creek is faulted and dips are
tess regular.

Coal Seams

No seams thick enough to mine are exposed in the
canyon of Dunlevy Creek, or in the canyon or upper reaches
of the east fork of Dunlevy Creek and its tributarie.. Only
thin seams were found on Gravel Hill and Cust Creeks.

At and near the Packwood mine, at the south end of
a spur from Butler Ridge, two thin seams occur in the upper
conglomerate—bearing part of the Dunlevy formation.

The No. 1 seam, worked in the mine, has an average
thickness of 30 inches in the upper level and 20 inches in the
lower level. The lower 10 inches of the seam is finely
crushed, and movement is also indicated by slickensides on
both walls. The foot-wall rock is silty shale and the hang-
ing-wall consists of hard, massive sandstone. The seam was
sampled at the face in both levels. Analyses are as follows: