NOTES ON GLACIATION IN THE SANGRE DE CRISTO 
RANGE, COLORADO’ 
C. E. SIEBENTHAL 
In connection with an examination of the artesian basin of the San 
Luis Valley, Colorado, In 1903, several opportunities were had to 
make observations in the Sangre de Cristo Mountains, and various 
notes on the glaciation of that range are here recorded. 
Attention has heretofore been called to glaciation on the eastern 
slope of these mountains by J. J. Stevenson,” who describes and figures 
the well-developed Grape Creek moraine, about midway of the range 
north and south. F. M. Endlich? also alludes to small indications, 
of glaciation, so uncertain in their character that he prefers to 
disregard them altogether. As a matter of fact, not only has the 
range suffered general glaciation, but even at present contains two 
living glaciers. 
No pretense is made to completeness, individually or collectively, 
for the following notes. ‘The observations were for the most part 
confined to the western side of the range. The sharp precipitous 
western slope merges into the great alluvial slope which skirts the 
western base of the range. Each stream valley which heads against 
the crest-line has its valley trains of glacial débris, which ordinarily 
reach down to and, at an elevation of about g,o0o to 9,500 feet above 
tide, crown the alluvial cones making up the alluvial slope. 
The northernmost glaciation observed is in Black Canyon, just 
east of Orient Station on the Denver & Rio Grande Railway. Here 
are lateral moraines on each side of the creek 100-200 feet in height, 
and reaching nearly or quite to the lower end of the canyon. 
The next canyon to the south in which morainic deposits came to 
the notice of the writer is Willow Creek, east of the village of Crestone. 
1 Published by permission of the Director of the United States Geological Survey. 
2U. S. Geographical and Geological Survey West of the tooth Meridian, Vol. III 
(1875), PP- 434) 435- 
3 U. S. Geological and Geographical Survey of the Territories, Annual Report, 1875, 
p. 220. 
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