618 ALLEN DAVID HOLE 
Lake was a little less than 10,000 feet in elevation; the surface of 
the ice must, therefore, have had a general slope to the northwest of 
from 250 to 500 feet per mile, and the moraines about Trout Lake 
are to be considered as recessional, or as ground moraines. 
Trout Lake is practically surrounded by moraines. Cross 
suggests’ that the lake may be formed by a dam due to landsliding. 
While it is quite probable that there has been some movement in the 
material below the lake of the nature of landsliding, it is also true 
that so far as sections are exposed in the débris below the lake the 
deposit is shown to be typically glacial, consisting almost entirely 
of unstratified drift with bowlders in variety, many of them striated; 
and since the topography is also such as is found in morainal 
deposits, that is, irregularly disposed hills and ridges, it seems not 
inappropriate to class the deposit as morainal even though there 
may have been some readjustment of the materials since the ice 
withdrew. On the west and south of the lake there are distinct 
ridges of drift at several points trending in general in a north-south 
direction; but much of the surface is quite irregular. East of the 
lake, the moraine belt is narrow, extending to an elevation not more 
than 100 to 200 feet above the water’s edge. To the southeast, 
morainal hills are found as far as the upper end of the artificial lake 
at 10,000 feet elevation. Southwest of Trout Lake they are con- 
tinuous over the divide into the basin of the Dolores River, and 
extend up to about 10,400 feet. In this direction small kettles 
occur. Below the lake (to the north), the moraines continue for 
one-fourth to one-half a mile at nearly the same elevation as at the 
lower edge of the lake. Below this morainal dam, just north of the 
abrupt eastward turn of the railroad, the bottom of the valley is” 
about 100 feet lower, some marshy areas occur, and the morainic 
hillocks are fewer and much smaller. 
Just northeast of the village of San Bernardo roches moutonnées 
occur, and a few rods farther north a low recessional moraine 
extends from the railroad to the east side of the valley. Sections 
of this moraine exposed along the railroad show some stratified 
drift near the top and unstratified lower down, with bowlders in 
variety, some of them striated. The lower part of the valley just 
t Telluride Folio, p. 10. 
