80

right limit near the upper end of this broad part, however, show n
evidences of glacial erosion, and appear to represent parts of the old
creek bottom formed at a time when the creek flowed at a considerably
higher level. It is at least evident that they were formed by stream
erosion before the deposition of the glacial drift that overlies them. They,
therefore, form the most promising placer ground on the creek. The main
bench crosses to the left side above the bend and agrees fairly well in
elevation with Cunningham “bar.’”’ How far downstream these benches
extend, or whether they cross to the other side lower down is not known
because they are concealed beneath glacial drift. They slope downstream,
in the parts where they have been exposed in mining operations, at a rate
greater than that of the surface of the valley flat. It is held by some of
the prospectors that the benches extend along the right limit all the way
down to the Bear claim, or at least that the old stream channel was in
that direction. At the Bear claim, however, the old channel worked was
about at the level of the present stream channel and the presence of rock
benches beneath the high gravel bank on the right limit was not proved.
The deep ground in the main valley from the Bear dam down to the Bear
claim has been tested only by the boring at the junction. The low values
obtained here and the great width of the valley bottom—suggesting that
the effects of glaciation were pronounced—discourage the view that a
rich undiscovered pay-streak exists, although it cannot be said that the
possibilities of this part of the valley have been exhausted.

Cunningham creek was especially affected by valley glaciation,
because it heads in one of the highest parts of the plateau region and flows
north. The narrow, rich pay-streak, mined in the early days in the
upper part of the creek, may have escaped erosion by the glacier on account
of the narrowness of the valley bottom, or it may have been produced by
glacial and post-glacial streams which concentrated gold that had been
derived from placers eroded and transported a short distance by the
glacier. This part of the creek has been regarded for many years as being
practically worked out, although occasional finds of small areas of work-
able ground, especially on the high bank on the left side above Cunning-
ham’s claim, have been made even in recent years, but none of these has
proved of sufficient value to warrant the installation of a mining plant.

Grouse Creek

Grouse creek, the lower part of which is shown on Figure 11, heads
with Antler creek in Bald mountain and flows north and northeast for
5 miles to Antler creek. It is joined near Antler creek by Pleasant Valley
creek flowing southeast. In the upper part, the stream flows for about
15 miles in a deep, steep-sided valley along the sides of which the bedrock
outcrops in many places, though it is mostly concealed by drift and by
the soil and thick forest covering. The valley bottom is flat, and forms
a beautiful alpine meadow such as is characteristic of the upland parts of
many of the valleys. No gold was found in this part of the creek. About
a mile lower down the stream turns abruptly towards the east, the
valley widens, and rock benches mined for gold in the early days occur
along the creek, Just below the bend a high, steep bank of glacial drift