GLACIATION IN THE TELLURIDE QUADRANGLE 617 
On both the east and the west sides of the central valley on the 
north side of Sheep Mountain is a medial moraine; on the east side 
the moraine extends from about 11,600 feet to 11,200 feet in eleva- 
tion, and is for the greater part of the way a sharp ridge from 15 to 
50 feet high; on the west side, the medial moraine is shorter and 
does not continue to be well marked below 11,400 feet. Besides 
the drift with striated bowlders already mentioned at 10,400 feet 
Fic. 7.—Landslide block of Potosi rhyolite, south of east from Trout Lake 
Looking north from 12,000-foot point one mile west of Pilot Knob. This block came 
to about its present position before the more recent glacial epoch. 
elevation, the cirque northwest of Sheep Mountain contains de- 
posits of bowlders in variety at 10,500 feet elevation west of the 
stream and at 10,800 feet more than a quarter of a mile farther east. 
Since the uncerlying rock here is shale, no roches moutonnées occur. 
Only the upper 500 feet of this valley is free from forests. 
No ice entered the valley from the slopes of Black Face Moun- 
tain lying on the west. The upper margin of the ice west of Trout 
