i stretch near the mouth of Wheaton Creek. The alternative ex-
planation, of course, is to attribute the over-deepening of
the Turnagain Valley to erosion by glacial ice, but the low
grade of Turnagain valley and absence of high ice gathering

} ground does not support that view. In the absence of any con-
i firmatory data the writer prefers to explain it by pre-glacial
stream action. The evidence for rejuvenation has been cited,
I consequently, over-deepening of the main stream or a hanging
relationship of the tributaries appear to be a logical result
of the process.

On the Peacock lease (No. 345), the southward projection
i of the lowest rock bench correlation is below the level of
the present creek. Farther up-stream the projection is close
to creek-level, but, up to the mouth of Alice Shea Creek, re-
mains below. This is interpreted as meaning that in late Ter-
5 tiary there was a canyon along Wheaton Creek, comparable to
; the present one. Furthermore, it is significant that the pro-
jection of the rock bench correlation southward from Wheaton's
camp corresponds with the mouth of a dry, southward-trending
gulley. The projected line being below creek-level on the
Peacock lease indicates in all probability that a buried late
Tertiary channel lies to the east of Barrington's camp. The
channel eventually joins Wheaton Creek and coincides with it
at a point less than 2,000 feet south from the camp.

The late Tertiary stream rejuvenation and down-cutting
was followed by an advance of glacial ice during the Pleis-
tocene. The pre-glacial topography and drainage was modified
to a slight extent by glacial ice. It is believed that there
were two ice advances separated by an interglacial stage.
Consequently it is not possible to discriminate between the

erosional features of the two ice advances. However, the

erosion, in the valley-bottom, by neither was sufficient to
disperse gold which is believed to have been set free and
partly concentrated during the Tertiary. Depositional fea-
tures are clearly the result of the last ice advance.

Ridges and summits up to 6,500 feet elevation are round-
ed and have a scattering of glacial erratics. The ice at its
| maximum extent must have reached to at least that height.
High jagged peaks above 6,500 feet elevation do not necessar-
ily imply that they stood above the ice level, and it is
possible that King Mountain (7,890 feet) was covered with
glacial ice

Glacial erratics of various kinds are scattered over the
high points of the area but insufficient knowledge of the sur-
rounding geology prohibits positive deductions regarding the

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