60 FORTYMILE, BIRCH CREEK, AND FAIRBANKS PLACERS, [bull. 251* 
The bed rock in most of the valley varies from a rather massive, 
blocky quartzite to a mica-schist. A structure observed at one 
locality showed a strike N. 00° E. and a dip of 20° to 25° to the 
southeast. The rocks show evidence of minor folding and contain 
numerous small quartz stringers. Intrusive granite is very promi- 
nent in the region farther east, especially on Ketchum Creek, only a 
few miles east of Deadwood Creek, where weathering has produced 
very striking pinnacled forms from this rock in the valley of the 
creek itself. On Deadwoool Creek it is not so conspicuous, but forms 
the bed rock over a considerable portion of the creek. Dark-colored, 
more basic rocks occasionally occur. 
The gravels are composed of the varieties of rock outcropping in 
the drainage area and consist .mostly of subangular fragments of 
comparatively small size, more or less irregularly arranged, con- 
taining much finely broken material of the same nature. The depth 
to bed rock varies in the creek from 3 to 12 feet, and on the bench to 
the west, as far as known from work already done, from 6 to 20 feet. 
The gravels in the creek vary in thickness up to about 8 feet, and 
there is generally but a small amount of top dirt to be removed. 
The values are sometimes found through the whole thickness of 
gravel, but are generally close to bed rock and are found also in the 
bed rock to a depth of 2 or more feet. When the bed rock is mas- 
sive and divided into blocks through jointing, values are found 
sometimes to a depth of 4 feet along the joint planes. The width 
over which pay is found varies from about 25 to 300 feet. The 
average width is said to be from 150 to 200 feet, and the average 
value of the ground for the entire creek to be about $50 to the box 
length of 12 by 16 feet. Some ground has averaged much more, 
values ranging from $100 to more than $200 having been obtained in 
1903. Not much work has been done thus far on the bench to the 
west side of the valley, and little is known of the extent or values of 
the gravels found there. In a few cases, however, these gravels are 
being investigated and values have been found. At one locality 
20 feet of gravel lie on a rather massive quartzite bed rock at a 
level of 20 feet above that of the adjacent creek. Little gold is 
found in the gravel; it is mostly on bed rock and along the joint 
planes to a depth of 4 feet within it. From something over half a 
box length of ground, 16 by 12 feet, $128 had been washed, which 
would give an average for the amount of dirt moved of something 
more than $1 to the cubic yard. Two nuggets had been found 
worth $8 and $10, respectively. This locality is important in point- 
ing out the possibility of the extension of the pay over portions of the 
bench. The creek gold is generally flattened and at the entrance of 
the valley is rather flaky. The coarsest piece found thus far on the 
creek was worth $122. That found on the bench is rougher and more 
