174 ALASKAN MINERAL RESOURCES IN 1906. 
alluvium, forming the white gravels of Dahl Creek and the bench 
gravels of the lower part of Quartz Creek and of the Kougarok, and 
these same gravels are found along the front of the upland near Gar- 
field and Turner creeks; (3) this older gravel series is not believed to 
carry values, though it is known to be more or less auriferous. 
This last conclusion is borne out both by the prospecting and by 
theoretical considerations. In general the rich placers of the penin- 
sula occur in alluvium which is subangular and which was deposited 
under conditions of subaerial decay rather than during floods. These 
bench gravels are, however, well rounded and stratified and appear to 
have been laid down during periods of flood, which are not favorable 
to a concentration of values. 
So far as known to the writer, the base of these gravels on bed rock 
has never been prospected. There is no reason to believe that the. 
basement member may not be gold bearing, and in the opinion of the 
writer the chances of finding gold at depth is sufficiently good to war-i 
cant the outlay of the cost of prospecting them to bed rock. 
Though it is not proposed to describe them in detail, a few notes on 
the different creeks will be appended. 
COFFEE CREEK. 
A peculiar auriferous deposit was opened up during the winter of 
1 906 on t he upper part of Coffee Creek. Some rich placer ground was 
found in the angular talus of the valley slope, which appeared to be 
almost in place. The gold occurs in 4 to 7 feet of angular schist and 
quartz debris and weathered schist bed rock covered by 18 to 20 feet 
of muck. The quartz is iron stained, but does not appear to be aurif- 
erous, and the gold probably came from the schist. The gold is angu- 
lar, spongy, and bright colored. These facts indicate that the mate- 
rial mined is the decomposed surface of a mineralized zone. The 
deposit has been traced about 1,000 feet, but being buried deeply its 
boundaries are not well known. It is indicative of the source of the 
gold and suggests at least the possibility of finding lode deposits which 
may carry values. 
The other placers of the upper part of Coffee Creek are, as a rule, 
buried under an overburden of muck 10 to 20 feet thick. The gravels 
are chiefly schist and vary from 3 to 7 feet in thickness. Bench 
gravels similar to those of lower Quartz ('reek occur near the mouth of 
Coffee Creek and are here said to carry some gold. 
DAHL CREEK. 
A bench at the mouth of Dahl Creek, 20 feet above the present 
stream bed, has been a large producer. A section at this poini is as 
follows : 
