SHASTA EOUTE SEATTLE TO SA:N' PEANCISCO. 



65 



growth 



I slates make rugged slopes and the forest 

 The light-colored digger pine (Pinus sail- 



wi 



Delta. 



habit of branching, becomes prominent. As, 



Elevation i,m feet, with it are live oaks, buckeyes, and shrubs character- 

 seattieG59mW^. ^^^ic of lowcr altitudcs and drier climate than those 



Mount 



From Delta 



mountain 



mines 



Half a mile below Delta, on the right (southwest), is a bluff of slate 

 overlain by 10 feet of gold-bearing gravel deposited by the river when 

 its bed was about 70 feet higher than now. The g.avel is covered by 



Mount Shasta, as illustrated in fionire 



Since the 



lava flowed down the canyon the river has cut not only through the 

 lava and gravel but 60 feet into the slates. 



Figure 11.— Section of canyon of Sacramento River just below Delta, Cal. fl, Terrace formed by rem- 

 nant of lava stream that flowed do\sTi the canyon of the Sacramento from Mount Shasta to a pctnt 10 

 miles south of Delta; &, ancient gravel bed of the Sacramento covered by the lava fiow from Mount 

 Shasta (gravel is auriferous); c, slates of Carboniferous age in which the canyon is cut; d, portion of 

 the canyon (70 feet) cut by the river since the lava flowed from Mount Shasta. 



Tlie old California-Oregon wagon road crosses the river and railroad 

 at Antler fSmithsonV and the Pacific Hi^hwav crosses about 2 miles 



and 



farther south. Near milepost 287 the lava flow 

 from Mount Shasta ends. Its entire length is about 

 50 miles. Here the railroad crosses the river 



goes through a tunnel. 

 Between some of the beds of sLxtc and sandstone, which are well ex- 

 posed along this part of the route, are beds of lighter-colored gray con- 



Antler. 



Elevation 974 feet. 

 Seattle 665 mOes. 



Elmore. 



Elevation 804 feet. 

 Seattle 672 milfto 



glomerate, generally less than 10 feet thick. 



Most 



consist 



siliferous limestone. 



lim 



exposure to the weather, dissolve away, leaving 



The coarsest conglomerates of 



1 be seen from the tram. 



formation, to which all these rocks belong, occur near 



Dpvnnian fossils. The 



Elmore, whera th^ limestone nebbles contain 



rocks 



96286 



614—1 



5 



