66 GLACIAL AiSTD SURFACE GEOLOGY OF THE PACIFIC COAST. 



southern indications of former glaciation seen in the Rocky Mountains, have 

 been described somewhat in detail by Mr. F. M. Endlich.* 



The Weeminucke glacier is indicated, on a sketch-map accompanying the 

 article cited, as having had a length of five or six miles, and there was a 

 smaller one parallel with it on the northeast, which came down the Huerto 

 branch of the Rio Piedra. These appear to have descended to about the 

 same level, — 8,000 feet above the sea. Mr. Endlich describes the glacier 

 of the Rio Chama as having been of much greater extent than those just 

 mentioned. It occupied a position on the summit of the volcanic plateau, 

 at the head-waters of Rio Conejos and Rio Chama. In the ascent of the 

 latter river the first indications of former glacial activity were met with at 

 an altitude of 8,450 feet. On the volcanic plateau above, at an elevation of 

 about 11,800 feet, and higher up for four miles farther north, the rocks are 

 beautifully striated and polished. The length of the ancient glacier is indi- 

 cated on the general map of Colorado as about eight miles. Mr. Endlich 

 says that more than twenty-five square miles must have been covered on the 

 jjlateau by this extensive mass of ice, which appears to have been chiefly 

 developed at an elevation of about 12,000 feet, and to have descended to 

 about 8,000 feet above the sea-level. The above-mentioned occurrences, 

 and some " small indications of local glacial action " observed in some of the 

 caiions of the Sangi-e de Cristo Range, of which Mr. Endlich remarks " that 

 there is no certainty as to their true glacial character," are said by him to 

 include all the undoubted glacial regions of Southern Colorado that he had 

 occasion to visit during 1874 and 1875, which were the years when the work 

 was being carried on in that region. At all events, they are the only ones 

 indicated on the final map puljlished by the Survey. 



Although the geological maps of Colorado, published under Dr. Hayden's 

 direction, do not indicate the existence of any moraines along the eastern 

 slope of the so-called Front Range, or that portion of the chain which faces 

 the Plains, yet there are occasional references in the publislied Reports to 

 evidences of former glacial action in this part of the Rocky Mountains. A 

 detachment of the party taken to Colorado by the writer, in 1869, explored 

 the vicinity of Gray's Peak, which is in latitude 39° 38', and 14,341 feet 

 above the sea-level. They also followed down Clear Creek to the level of 

 the Plains at the base of the ramie. Professor Brewer conducted this sub- 



o 



* In Deport of U. .S. Geological and Geographical Survey for 1875, p. 206, under the head of "Ancient 

 Glaciers in Sonthern Colorado." 



