GLACIATION IN THE TELLURIDE QUADRANGLE, 
COLORADO 
ALLEN DAVID HOLE 
Earlham College, Richmond, Ind. 
PART III 
DESCRIPTION OF DEPOSITS OF EARLIER DRIFT 
RIDGES EAST AND WEST OF EDER CREEK 
On the east side of Eder Creek, from the edge of the southern 
part of the ridge down to within 200 or 300 feet above the stream, 
and thence northward in an irregular belt a quarter of a mile or less 
from the stream, the surface shows plentiful bowlders up to 15 feet 
in diameter. These large bowlders are mostly rather rough and, 
angular, and consist chiefly of Potosi rhyolite or Silverton, and 
Telluride. On the top of the ridge, the deposit contains fewer 
bowlders at the surface, their size is on the average less, and a 
greater variety of rocks is included—San Juan being noticeably 
more abundant than on the slope to the west. A striated bowlder 
was found on the top of the ridge at 10,500 feet. Farther north, 
within a quarter of a mile of the col that connects this ridge with 
the mountain to the north, an exposure on the west side of the ridge 
at about 10,300 feet shows an unstratified deposit of clay, gravel, 
and bowlders in variety; on some of the bowlders faint striations 
were observable. On the east side of the ridge, glacial drift 
including well-striated bowlders occurs down to about 10,400 feet, 
joining here with the hummocky, irregular topography which has 
already been described. 
The boundaries of the area just described are not clearly marked 
on all sides, but are approximately as mapped. 
This area is classed as older drift because of (1) its topographic 
location, far above the clearly marked limit of the recent glaciation: 
(2) its composition, differing as it does from the more recent drift 
in the presence on the surface of many large, weathered bowlders, 
710 
