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Mines - Morris Summit
The property is
the Prince, Gold, and Summit Lake Crown- granted claims on the west side of Summit Lake about one
mile
from the north end. Prior to the building of the Granduc road the deposit had difficult access, but it is
now
easily reached from the road at the north end of Summit
Lake. The property was visited several times by the
writer, but the two adits comprising the underground workings each time
contained " bad air."
The country rocks are crudely
stratified green volcanic conglomerates and breccias
with intercalated, thin, volcanic sandstones and tuffaceous bands.
Bedding generally
dips steeply and trends westerly, but the over-all rock structure has
been truncated
and obscured by the Summit Lake stock and by the local dyke swarms. Along the contact with the
Summit Lake pluton the epiclastics have been variably indurated and hornblendized, apparently in relation to the grain size of
the intruded material. Coarse, dark-brown hornblende crystals up to 4 inches long are
found in volcanic sandstones and fine-grained conglomerates up to 100 feet from
the contact, whereas in the coarse conglomerates and breccias the hornblende was best
developed in the fine-grained andesitic rock fragments rather than in
the matrix.
Alteration along the dyke
contacts includes variable induration, pyritization, and epidotization.
In this section the Summit Lake
stock is typically a white-weathering, light-grey homblende granodiorite with irregular quartz-rich (20 per cent to 35 per
cent) zones.
The dykes have been divided into three local groups on the basis of
composition and crosscutting relationships.
The oldest are fine grained, dioritic, and resemble
the Bear River Pass type but at the mine have been called
" green dykes." The younger dykes are porphyritic granodiorites which
texturally
and compositionally resemble the Premier dyke-swarm type.
The youngest are typical lamprophyre dykes which cut all rock units. The mineralization and apparent structural controls were described at length
by White (Ann. Rept., 1946) and Black (Ann. Repts. 1947, 1948) when the property
was active and when the underground geology and diamond-drih core was accessible.
The property, located by Ted
Morris and associates of Stewart in 1930, was developed by the Premier Gold Mining Co. Ltd. in
1931. In 1934, The
Consolidated Mining and Smelting Company of Canada, Limited, drilled several deep
holes, one of which intersected good gold mineralization in the area of the present
3600-level No. 1 zone. In 1936, Salmon Gold Mines Ltd. started the 3600-level
adit which was extended 1,500 feet over the following three seasons.
In 1945, Morris Summit Gold Mines, Limited, acquired the property and
completed 3,724 feet of diamond drilling. In 1946 the 3000 level was
started and 2,137 feet of diamond drilling completed
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