434 OSCAR H. HERSHEY 



developed in rock. This high channel represents the floor of a 

 comparatively broad valley, of which only a very few remnants 

 remain. It dates back at least as far as the Red Bluff epoch. 

 There are no traces of any higher river deposit in this region. 



The valley carved below the main upper terrace at the mouth 

 of Rush Creek may be 500 to 800 feet wide. In it are two main 

 terraces, both well defined. The lower is i 5 to 20 feet above the 

 river level, and is trenched by the winding canyon of the present 

 river, which is here several times as wide as the low-water stage 

 of the stream because the soft granite erodes easily. The second 

 terrace may be 50 feet above the river. These two lower terraces 

 have fewer and less rotten large granite bowlders than those 

 higher. 



At Miller's suspension bridge the terraces, here well defined, 

 are at about 20, 55 and 120 feet respectively. The rock is 

 harder and the lower canyon getting smaller. The river next 

 swings into the north bluff, cutting away the terrace system but 

 leaving it well defined on the south side. The next swing is 

 into the south bluff and cuts it out on that side. 



From here to Big Bend Creek, the north side of the valley 

 contained abundant remnants of the main upper terrace, which 

 have nearly everywhere been mined off. The gravel layer was 

 thin and contained few large bowlders. Over it there was, in the 

 first remnants, 10 to 20 feet of indistinctly stratified local debris 

 such as in the torrent fan at Cooper's mine (but less coarse) 

 discussed in another paper ^ and the significance of which will 

 come out later in this. In places it contains much clay and is 

 red in color. The surface of this terrace sloped distinctly toward 

 the river, but its rock bench, in so far as it constitutes Channel C 

 is level. The latter is well defined on four points and stands 

 about 75 feet above the river. One can look across these points 

 and see that there is absolute correspondence in height of the 

 flat rock platforms. 



The rocks are here hard hornblende schist and the canyon 

 narrow from the upper terrace level down, but in it there are 



' "Some Evidence of Two Glacial Stages in the Klamath Mountains in California," 

 American Geologist, Vol. XXXI, March, 1903. 



