The Caldwell tribune. [volume] (Caldwell, Idaho Territory [Idaho]) 1883-1928, 1897-08-28
Geological Survey RepOrt-Can Mine
the Year Around.
VERY RICH PAY STREAKS IN PLACES.
Only Partly ExpIOrPd-PreciOus Metal
Found All Over The Territory Best
Gravel Found Near Gold Bearing
Rocks and Heads of Streams.

A surveying party of the Geological
Survey went somewhat extensively in
to the ukon gold fields last year. a
preliminary report of their explorations
is now available. At the head of the
expedition was Mr.. J. Edward Spur, a
leading authority on gold mining The
report says:
"The party crossed to the head water
of the Yukon by the Chilkoot Pass
and proceeded by boat down the Yukon
to Forty Mile creek. They found on
arrival there that they could traverse
the country in all directions, through
canyons and over mountains, having
Indians act as packers. The party
tTaveTsed the valley of the Yukon
from the British boundary on the east
to mouth Of the river on the west. All
of the known placer deposits were ex-
amined and the origin of gold in them
was traced to the veins of quartz along
the various streams entering the Yu.
kon.
sufficient data were secured to es-
tablish the. presence of a gold belt
three hundred miles in length in Alas
ka which enters the territory near the
mouth of forty mile creek and extends
westward across the Yukon valley at
the lower ramparts. Its further ex-
tent is unknown.
ut is the opinion of the geologist in
charge of the expedition that it is en-
tirely practicable to prosecute quartz
mining throughout the year in this re
gion. He also discovered along the
river large areas of rocks containing
hard bituminous coal.
Running in direction little west
of northwest, throguh he.territory ex-
amined, is.a broad, continuous belt of
highly altered rocks. To the east this
belt is known to be continuous for one
hundred miles or more in British ter
ritorY. The rocks constituting this
belt are mostly crystalline schists, asso-
ciated with marbles and sheared quartz
ties, indicating a sedimentary origin
for large part of the series. These
altered sedimentarY rocks have been
shattered by volcanic action, and they
are pierced by many dikes of eruptive
rocks.
''In the process of mountain building
the sedimentary rocks have been sub.
jected to such pressure and to such al |
formation from attendant forces that
they have been squeezed into the con-
dition of schist, and often partly or
wholly crystallzed, so that their origi-
nal character has in some cases entirely
disappeared. In summarizing, it may
be said that the rocks of the gold.belt of
Alaska consist largely of sedimentary
beds older than the carboniterous
period, that these beds have undergone
extensive alienation, and have been |
elevated into mountain ranges and cut
through by a variety of igneous rocks
Throughout these altered rocks |
there are found veins of quartz often
carrying pyrite and gold. It appears
that these quartz veins were formed |
during the disturbance attending the |
uplift and alienation of bed. Many
of the veins have been cut, sheared and
torn into fragments by the force that
has transformed sedimentary rocks in
to crystalline schist, but there are
others, containing gold silver and cop
per, that have not been very much dis
turbed or broken.
'These more continuous ore bearing
zones have not the character of ordin.
airy quartz veins, although they contain
much silica. Instead of the usual
white quartz veins the ore occurs in a
sheared and altered zone of rock, and
gradually runs out on both sides. So
far as yet known, these continuous
zones of ore are of relatively low grade.