GLACIATION IN THE TELLURIDE QUADRANGLE 525 
On the west side of Mill Creek where it joins the valley of the 
San Miguel, a short, well-defined ridge extends south of west nearly 
to Eder Creek. Near its upper end its crest is about 500 feet above 
the bed of the stream (Mill Creek), and rapidly decreases in 
elevation toward the southwest. On the side of this ridge away 
from Mill Creek its slope is short, and joins, in its upper part, the 
unglaciated slope of the ridge lying between Mill Creek and Eder 
Creek; farther down it joins the glacial débris of the main (San 
Miguel) valley. No ridges transverse to Mill Creek appear in 
connection with the lateral moraine; either no terminal moraine 
was formed by the glacier occupying the valley of Mill Creek, or, 
if formed, it has been carried away. 
Upstream from the lateral moraine just referred to, one-fourth 
to one-half a mile from where Mill Creek enters the San Miguel 
valley, there is an accumulation of glacial débris lying near the 
stream and up to about 9,400 feet in elevation. This accumulation 
forms what appears when viewed from the upstream side to be an 
irregular, narrow terrace whose top is not more than too to 150 
feet above stream. Above the accumulation, the valley becomes 
slightly broader and for about one-fourth of a mile is sufficiently 
level to indicate that ponding of water with accompanying silting- 
up must have taken place. This more level surface is in sharp 
contrast with the steep slope on the same side of the stream near 
the San Miguel valley. On the east side of Mill Creek, no terrace 
appears corresponding to that on the west; some glacial débris is 
present, however. This deposit of drift at 9,300 to 9,400 feet in 
elevation is interpreted as a recessional moraine which for a time 
partially dammed the stream. 
The maximum thickness of.ice in the valley of Mill Creek was 
probably from 500 to 800 feet. 
VALLEY OF CORNET CREEK 
The head of this valley is a cirque with precipitous walls, steep 
talus slopes, a bottom showing some rock in place, some loose 
bowlders, and some finer fragmental material which in places 
supports a sufficient growth of low plants to conceal the rock 
fragments under a covering of green. The tributary valley from 
