214 ALASKAN MTNERAL RESOURCES TN 1906. 
The slopes are deeply furrowed by narrow V-shaped valleys. The 
drainage on the south runs into Moose Creek, a stream that heads far 
hack in the foreground of the mountains, flows close along the south- 
ern base of the ridge in a finely benched open valley, and finally cuts 
a canyon through the ridge to flow northward to the Bearpaw. The 
streams that drain the northern slopes have long lower valleys limited 
on either side by the edges of low tonguelike spurs. 
The material of the ridge is for the most part a highly metamor- 
phosed and closely folded quartzitic schist, with garnetiferous quartz- 
mica schist, carbonaceous schist, a small amount of interbedded crys- 
talline limestone, and much greenstone, part of which at least is 
intrusive. This formation is like that at the canyon of Cantwell River, 
south of Healy Creek, and is the same in character as that of the Fair- 
banks region. The occurrence of gold also and the associated min- 
erals are the same for the most part as in the Fairbanks region. The 
Ton nation lias in general a northeasterly strike. The foreground of 
the mountains to the east is formed of hornblende granite and granite 
porphyry and somedikesof granite porphyry occur in the schists. Small 
areas of the coal-bearing rock occur in the region and coal from a fork 
of Moose Creek is utilized to some extent for blacksmithing purposes. 
The extension of the schist area to the southwest has not been deter- 
mined. Topographically it terminates apparently at McKinley River; 
to the northeast it is probably continuous with t he schists of the Cant- 
well Canyon. The rocks of the Alaska Range t o the east are in general 
black slates partly altered by contact metamorphism, greenstones, 
intrusive granitic rocks, and volcanics. 
THE CREEKS. 
The creeks head in open V-shaped areas formed by the convergence 
of two or mote small tributaries. The lower parts of the valleys are 
narrow canyons. Where these join the main valleys benching becomes 
prominent and their deposits merge into the tremendous body of 
gravels that has been spread far and wide from the Alaska Range. 
This material is for the most part easily distinguishable from the 
schistose gravels of the creeks.. 
The creeks where mining has been done 4 are located on both sides 
of the ridge. Named from east to west on the south side of the ridge, 
round the west end and eastward along the northern slope, they are as 
follows: Spruce, Glen, Eureka. Friday, Glacier, and Caribou. 
SPRUCE CREEK. 
Spruce Creek flows its last mile in the valley of Moose Creek. Above 
tins part of its course for about 1 J miles the valley is narrowly V-shaped 
and then near the head becomes more open. The grade in the narrow 
