630 ALLEN DAVID HOLE 
bounding walls meet at some points, producing the effect of a valley 
less well cleaned out. The bottom shows the same alternation of 
steep and gentle slopes as is found in other cirques. 
The second valley south of Navajo basin heads in a shallow; 
double-headed depression on a steep southern slope. At about 
12,500 feet in elevation the generally steep slope is flattened into a 
shelf or bench perhaps 20 rods in width; back of this shelf the rock 
wall rises with a steep slope, and on the east and west are short side 
walls. Below this shelf, talus slopes divided in the middle by a 
north-south ridge extend down to a second more nearly level area 
between 11,500 and 11,800 feet in elevation; the topography on this 
shelf is irregular, and the surface is overgrown with low plants. 
Below this, steep, rough-faced cliffs appear, at the base of which the 
more level bottom of the valley begins. The underlying shale is 
here deeply weathered and eroded in places, showing bare ridges | 
and gullies with but little glacial débris. Farther down the valley, 
however, glacial drift covers the surface, and a little beyond the 
edge of the quadrangle typical morainic topography occurs, viz., 
kettles inclosed by irregular hills containing bowlders in variety, 
many of which are striated. 
At elevation 11,200 feet on the eastern side of the valley glacial 
drift including bowlders in variety up to 8 feet in diameter forms a 
ridge extending in a northeast-southwest direction for more than 
half a mile. The southeast slope of this ridge is gentle, grading off 
gradually into the unglaciated area; the northwest slope descends to 
the valley 100 feet or more at an angle of 30° to 35° with occasional 
exposures due to recent erosion or landslides. This ridge, there- 
fore, constitutes. a lateral moraine, the elevation of whose crest 
above the bottom of the valley is due in large part to the erosion of 
the underlying formations in which the stream has cut its valley. 
The maximum thickness of the ice in Navajo basin and in the 
valley next south was probably not less than 1,500 feet; in the 
second valley south of Navajo basin, probably not more than 
400 feet. 
VALLEY OF KILPACKER CREEK 
The cirques at the head of this valley are free from glacial 
débris. The broader one to the east is cut wholly in a formation of 
