CRATER LAKE, OREGON 



39 



Reference lias already been made to the glacial phenomena of 

 the outer slope of the rim. There are boulders not only upon 

 the surface, but also in piles of glacial gravel and sand si»read 

 fiir and wide over the southerri and western portion of the rim, 

 extending down the watercourses in some cases for miles to 

 broad plains thn)ugh which the present streams have carved the 

 deep and picturesque canyons already observed on the ascent. 

 At many points the lavas are well rounded, smooth, and striated 

 by glacial action. This is true of the ridges as well as of the 

 valleys, and the distril)ution of these marks is coextensive with 

 that of the detritus. 



A feature that is particularly impressive to the geologist mak- 

 ing a trip around the lake on the rim crest is the general occur- 

 rence of polished and striated rocks, in place, on the very brow 

 of the cliff overlooking the lake. The best displays are along 

 the crest for three miles nortlnvest of Victor rock, but thev occur 



GLACIATED CREST OK KIM OF CRATER LAKE 



From a I holograph b\ M. .l/. Hc.:eUine 



