GLACIATION IN THE TELLURIDE QUADRANGLE 527 
VALLEY OF MARSHALL CREEK 
Marshall Creek drains Marshall basin and Middle basin, lying 
in the Telluride quadrangle, and Savage basin lying for the most 
part in the Silverton quadrangle. All these basins, as well as the 
valley of Marshall Creek below, are practically free from glacial 
débris; except for accumulations of talus and rock streams, rock in 
place is everywhere at the surface. Roches moutonnées occur at 
many points, and striae are abundant, their direction coinciding in 
general with the direction of the stream courses. Special illustra- 
tions of roches moutonnées may be mentioned as follows: 
1. In the northwest part of Marshall basin, beginning at an 
elevation of 12,400 feet and including an area one-fourth of a mile 
square below that elevation, many roches moutonnées occur; striae 
within this area have directions varying from S. 25° E. to S. 35° E. 
2. At an elevation of 11,300 feet on the north side of the road 
near the turn from northwest to west, two sets of striae are plainly 
marked; one set has direction S. 5° to 10° W.; the other set, not so 
deeply cut, about S. 45° W. 
In the upper part of the basin the western slope is covered by a 
long talus slope, completely concealing the rock in place on that 
side. In the northeast part, at an elevation of from 12,500 to 
12,800 feet, is a small rock stream. 
In Middle basin a shallow lake occupies a rock basin; the 
outflowing stream passes through a channel about 1o feet deep. 
Northwest of the lake a ledge of rock in place too feet high shows 
roches moutonnées, but no striae. A little higher, at an elevation of 
nearly 11,700 feet, in both the east and the west branches of Middle 
basin rock streams are found extending from the base of the talus 
slopes which lie at the foot of the precipitous bounding walls of the 
valley. These rock streams are of two periods; the more recent 
are composed of fragments fresh in appearance, angular, and bare 
except for lichens on some of the surfaces. The older lie at the 
lower or outer edge of the more recent, the rock fragments are much 
disintegrated, so that the crests of the ridges are less sharp, and soil 
enough has accumulated to support vegetation, making the surface 
appearance that of rounded, green hills instead of bare ridges of 
angular fragments. 
