TERRESTRIAL DEPOSITS OF OWENS VALLEY 711 



graph (Fig. 1) shows the two fans, South Fork flowing in the low 

 place, and North Fork leaving its fan for the depression. This 

 shifting of streams to the inter-fan areas is suggested as a common 

 and efficient process in the tying together of fans, making piedmont 

 alluvial plains, or bajadas. 1 By this shifting, fans are made between 

 fans, tying them together and tending toward the union of the fans 

 into one plain. 



CHANNELS AND RIDGES 



Low ridges and shallow depressions on the individual fans con- 

 stitute topographic features of a second order. These are the 



3HI* *4m • £S» 



Fig. 1. — A photograph of the fans of Oak Creek, showing South Fork (ab) flowing 

 in the inter-fan depression, and North Fork (cd) leaving the fan to join South Fork in 

 the depression. 



channels and depositional features of the streams which deposited 

 the fans. The depressions are more noticeable than the ridges. 



The depressions are, as a rule, about 10 ft. deep and less than 100 

 ft. across, though at a maximum they reach a depth of 20-25 ft. 

 and a width of quite 100 ft. Their bottoms are usually flat and 

 their slopes as steep as the material will permit. The elevations 

 are less numerous than the depressions, and have less relief. They 

 are seldom more than 5 ft. above the surrounding plain, and their 

 height in many cases is only equal to the diameter of the individual 

 bowlders of which the ridges are composed. The ridges consist 



1 The term bajada has been suggested by C. F. Tolman (Jour. Geo!., XVII [1909], 

 141) to replace the longer term commonly in use. It has the advantage of brevity, 

 but lacks the explanatory value of the older term. 



