40 



II. E. Gregory — .1 Gcolor/ic Rebottftaissance 



cirques at valley heads, and lake-dotted morainal accumulations 

 are characteristic features. For the Cuzco region as a whole 

 the lower limit of Pleistocene ice may be placed at an elevation 

 between 12,500 and 13,000 feet, its position between these 

 levels depending on the topography. These figures for the 



Fig. 25. 



:■■-■" ■- ; \k 



Fig. 25. Moraines at La Raya Pass. 



limit of glacial action in the Cuzco Valley do not apply 

 generally to southern Peru. Diverse conditions prevail on 

 opposite sides of mountain crests, and even within a single 

 valley the terminal moraines are at widely different elevations. 

 Along the Urubamba the prominent moraines at La Raya, 110 

 miles (178 kilometers) southeast of Cuzco (fig. 23), lie high 

 above the railroad, which at this point has an elevation of 



