80 FAIRBANKS AND RAMPART QUADRANGLES. 
ORIGIN OF THE GOLD. 
The great difference in the richness of the several creeks flowing 
through the high bench of Minook Creek, and the variation in the 
richness of claims and size of nuggets on the same creek within the 
limits of the bench, sIioav that the gold is not evenly distributed 
through the gravels of the bench. Thus Hunter Creek has so far 
shown no rich claims, while Little Minook Creek has been very rich 
in places, and along the latter the gold is very coarse on the upper 
claims but grows much finer toward the mouth (PL III, j, k, and 1), 
showing that probably the larger part of the gold in the lower portions 
of the stream has been washed down from the upper claims. The gold 
in the bench gravels was probably concentrated from local gold-bear- 
ing zones in the rocks worn away above -the level of the high bench. 
How great a thickness of these rocks was disintegrated and carried 
away can not be told, but there may have been many hundred feet. 
The rocks were probably the same as those now forming the bed rock. 
The gold in the bench gravels is said to be well worn, but gold found 
in the gravels of a stream as large as Minook Creek is generally well 
worn, and in this case we have no clue as to the length of time through 
which wearing may have continued. 
OTHER TRIBUTARIES OF MINOOK CREEK. 
RUBY CREEK. 
Ruby Creek flows into Minook from the west side about 9 miles 
from the Yukon. It is a stream carrying 300 to 500 miners' inches 
(7.5 to 12.5 second-feet) of water, with a grade of about 150 feet per 
mile in the lower part. In this part the valley is broadly V-shaped, 
with steeply sloping sides. The upper part was not seen. 
The first pay was taken out of the creek in 1901, and the total prod- 
uct is said to have been $13,000 or $14,000, although this estimate 
may be a little high. About $5,000 was reported during 1904. No 
pay has been found above 1J miles from the mouth of the creek, but 
it is claimed that no holes have been sunk to bed rock on account of 
the live water in the gravel. 
The bed rock is the calcareous schist, garnetiferous mica-schist, car- 
bonaceous slate, chert, and grit, intruded by greenstones (diabase?). 
The bedded rocks strike almost north and south across the creek with 
the dip downstream (east). The alluvial deposits are 6 to 10 feet 
thick and 300 to 500 feet wide. In some places there is almost no 
muck and nowhere is its depth more than about 4 feet. The gravels 
are 5 to 7 feet in thickness and the total thickness of muck and gravel 
is 6 to 10 feet, averaging nearer the lower figure. No large chert or 
