THE SHASTA ROUTE AND COAST LIXE. 7 



Oregon Coast Range and are closely related in materials and in 

 structTire to the Sierra Nevada. The Klamath Mountains extend 

 south-southeastward into Cahfornia for 150 miles and overlap to the 

 east for SO miles the north end of the California Coast "Ranges. 



miles t 

 sharplj 



o 



more 



coast 



Cliannel, Thej 



great variety of character and of widely different 



ages. Their structure also is exceedingly complex. Tlie most 

 abundant rocks were formed in the Tertiary, Ci'etaceous^ and perhaps 

 Jurassic periods. Most of these rocks were deposited as sediments 

 on a sea bottom, but associated with the rocks so formed are in places 

 layers of lava or masses of igneous rock, which were forced in molten 

 condition into the sedimentary rocks. All have been folded and faulted 

 at several periods. Fmally erosion, or the action of moving water, 

 in the form of rahi, streams, and waves, aided by the crumbling effect 

 of weather, carved out the hills as they now appear. The resulting 

 forms reveal to one skilled in their internrotntinn snmo inrliVnfir^T^ 



to 



imderlyin 



meet 



more 



do not fall readily into the general threefold division of the Pacific 



of mountams that is so clearlv recognizable farther north. 



System 



ma 



iges, w^in wmcn tney nave commonly 

 them the Sierras de los Angeles, from 



Anereles. "Well-laiown 



thi 



Along the east side of the Pacific valley belt stretch two ctc 



ranees 



the south. 



as 



Cascade Range on the north and the Sierra Nevada on 

 The Cascade Range begins a few miles north of the 

 jtween Washington and British Columbia and continues 

 >r 650 miles to the vicinity of Mount Shasta in California, 

 dation of granite and of sedimentary rocks, such as sand- 

 ale, ranging in age from Carboniferous to Mocene. Some 

 ^ntary rocks and some associated igneous rocks have been 

 leat and pressure into crystalline lammated roclvs known 

 From Momit Rainier southwarrl the ix>cks Just men- 



an 



The volcanic cones, such 



nowecl from many vents at different times. 



as Shasta, Hood, an.d Rainier, which form strikin^ ....._ ...^ 



Cascades, represent a comparatively late stage of volcanic activity 

 and have been piled up on a preexisting moimtain range. 



The Sierra Nevada^ which continues southward the general line of 

 the Cascade Range, is of somewhat different structure and historv. It 



