LOR

Jeake

2s

13.

14.

stages in the pre-glacial downcutting of the creek.

The country was glaciated in two periods, separated by

an interglacial stage. Glaciation in neither was suf-

ficiently destructive to disperse the placer-gold accu-
mulations.

On Wheaton Creek a belt of serpentine 3 miles wide is
flanked by slate, argillite, limestone and andesitic Vor
eanics. The serpentine includes remnants of the sediment-
ary cover and is intruded by diorite and quartz-diorite.

There are many quartz stringers and veins in the slate
and schist. Some are mineralized with pyrite, but none
are known to be gold-bearing.

From 1935 to 1939, the total production of crude gold
has been 4852 ounces, valued at $140,708.00. This came
mainly from two leases on Wheaton Creek and one on Alice
Shea Creek.

The placer-gold being mined on the Peacock lease lies be-
low creek-level on flat-lying bedded clay which rests on
the bed-rock of an interglacial channel. On Alice Shea
Creek the gold is on bed-rock beneath a few feet of grav-
cl inecheubotLom of the creek. “On the Miva lease

(No. 402) the gold is a recent concentration on bed-rock
below creek-level in the lower canyon of Wheaton Creek.

The placer-gold on the Peacock lease did not migrate down-
stream from a source on Alice Shea Creek. The difference
in fineness of the gold strongly suggests that the placer
concentrations came from different sources.

Most of the placer-gold is believed to have come from the
erosion of auriferous quartz veins in the slate and schist.
Some on Alice Shea Creek appears to have come from an auri-
ferous pegmatite or feldspathic quartz vein. Some may have
come from mineralization in serpentine, though no veins in
serpentine have been seen.

On Wheaton Creek, where creek-grade and depth of gravel
are favourable, the auriferous gravel is worked by boom-
ing or ground-sluicing. On the Peacock lease the gravel
below creek-level is excavated by a 7/8-yard drag-line
shovel, and is washed in a moveable sluice-box. Any tail-
ings that accumulate and block the sluice-box are stacked
by a bull-dozer. On Alice Shea Creek the shallow gravel
is shovelled by hand into a string of 12-inch sluice-
boxes and the bed-rock carefully cleaned.

The hypothesis of the physiographic history, as developed

from the detail on Wheaton Creek, should be useful in dir-
ecting further prospecting on Wheaton and on other creeks

tributary to the head of the Turnagain River.

ee