GLACIATION. 249 
HUNTER CREEK GLACIER. 
The local glacier which occupied the Hunter Creek Valley has left its 
traces in the lateral moraine which lies at the base of Red Mountain. PI. 
XXXVIII is a view of the southeast side of this mountain, taken from across 
the Hunter Creek Valley. At the base is the lateral moraine of the Hunter 
Creek glacier, containing many huge bowlders, which are chiefly of granite. 
The upper limit of this morainal material is sharply defined, and above 
this there is no evidence of glacial action until the top of the moun- 
tain is reached, the rocks being all comparatively bare. On the very 
top, however, is the ground moraine of the earlier and more extensive ice 
sheet. 
The Hunter Creek glacier carved for itself a typical U-shaped valley, 
which may be seen in Pl. XXXIX. This view is up the valley, with the 
summits of the Sawatch in the distance. At some distance up the valley 
is seen a cliff projecting boldly and precipitously into the valley, and this 
seems to be a remnant of the pre-Glacial canyon. The valley does not 
extend westward farther than the highest terrace on Red Mountain, which 
is 400 or 500 feet above the Roaring Fork Valley, where it stops suddenly. 
This may be best seen by consulting the special topographical map of 
Aspen. The ending of the valley at this level’ shows that the Hunter 
Creek glacier flowed into the lake which covered the Roaring Fork Valley 
at a time when the latter stood at its highest level, as marked by the upper- 
most terrace. When the waters were drawn off from this lake, Hunter 
Creek found its way into the waters of Roaring Fork, turning at right 
angles to its normal course, and rushing down precipitously over the sides 
of the deeper Roaring Fork Valley. In this way it actually descends about 
500 feet in a horizontal distance of 2,500 feet, while above this turning 
point its course in its east-west glacial valley is very sluggish. In this rapid 
descent it has carved a rocky and often precipitous gorge in the Maroon 
sandstones and in the drift. The existence of remnants of pre-Glacial can- 
yons, both in Roaring Fork and in Hunter Creek, shows that these were both 
stream channels previous to the advent of the ice sheet, and it is probable 
that their pre-Glacial streams ran at approximately the same level. In the 
case of Roaring Fork, however, the local glacier has carved out a valley at 
least 500 feet deeper at Aspen than that of Hunter Creek. 
