THE FAIRBANKS AND RAMPART QUADRANGLES, 
YUKON-TANANA REGION, ALASKA. 
By L. M. Prindle. 
INTRODUCTION. 
The Yukon-Tanana region is the area extending westward from 
the International boundary between Yukon and Tanana rivers to their 
confluence. The greatest east-west dimension of this area is about 
300 miles, the greatest north-south dimension about 175 miles. The 
gold placers of Fortymile, Birch Creek, Rampart, and Fairbanks are 
situated in this region, and their economic importance has led to 
several years' work by the Geological Survey in making topographic 
and geologic maps and in studying conditions in the gold-producing 
regions. 
A topographic map of the* Fortymile quadrangle was made by 
E. C. Barnard in 1898 and was included in a preliminary report on 
the gold-producing regions. 
In 1903 a comprehensive scheme for mapping the entire remaining 
area was planned by A. H. Brooks, geologist in charge. In view of 
the facts that the Alaska surveys are for the most part of a recon- 
naissance character and that the region is thinly populated, the unit 
of publication adopted (see fig. 1) is a quadrangular area embracing 
4 degrees of longitude and 2 degrees of latitude. The first of these 
maps, that of the Circle quadrangle, which was made by parties under 
the direction of T. G. Gerdine and D. C. Witherspoon, was published 
in 1900 in a bulletin of the Survey. 6 The maps of the Fairbanks 
and Rampart quadrangles (Pis. IV and V, in pocket), with topog- 
raphy by D. C. Witherspoon and R. B. Oliver, arc published with 
this report. The area mapped on the Fairbanks sheet extends west- 
ward from the western edge of the Circle quadrangle to the 150th 
meridian, and the mapping has been continued northward to the 
a Prindlo, L. M., Gold placers of the Fortymile, Birch Creek, and Fairbanks regions, 
Alaska : Bull. U. S. Geol. Survey No. 251, 1905. 
b Prindle. L. M.., The Yukon-Tanana region, Alaska; description of Circle quadrangle: 
Bull U. S. Oeol. Survey No. 295, U><><;. 
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