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University of California. 



[Vol. 3. 



waters of the Big Arroyo and reaches in that region an altitude 

 of probably 10,500 feet. The Big Arroyo traverses the central 

 portion of the plateau in a deep narrow canon, cut below its level. 



The surface of the plateau is thinly timbered, but the rocky 

 surface may be seen through the trees. This surface deviates 

 from a plain, if we leave out of consideration the canons 

 which trench it, only by feeble relief which presents the appear- 

 ance of a very slight modelling. There is but one exception to 

 this, and even that might fairly come within the statement just 

 made. That is a low, rocky mound or smoothly rounded hillock, 

 which has an estimated altitude of about 200 feet above the 

 general level of the sloping plateau. The fact that this low hill 

 is a most striking feature of the surface of the plateau and is 

 without a fellow, is perhaps the best indication of its extreme 

 evenness. 



The area of this portion of the high valley land, or Chagoopa 

 Plateau, as bounded by the mountains of the Great Western 

 Divide, the Kaweah Ridge, and the canon of the Kern, is about 

 40 square miles. 



To the east of Kern Canon the Chagoopa Plateau has the 

 same character and the same general altitude along the brink of 

 the canon as on the west side, but is not so wide. It has more 

 the character of a terrace between the brink of the canon and the 

 steep slopes which lead up to the level of the Sub-summit 

 Plateau. South of Rock Creek this terrace has a maximum 

 width of about a mile and a half, or at most two miles, while, 

 midway between Rock Creek and Volcano Creek, it appears to be 

 almost, if not quite, eliminated by the close approach of the edge 

 of the Sub- summit Plateau country to the western brink of 

 Kern Canon. South of this point, however, remnants of it 

 again appear on the north of Volcano Creek. 



Within the drainage area of Rock Creek, terrace remnants of 

 the High Valley land extend as a long embayment within the 

 High Mountain Zone as far as the rear of the Siberian Outpost 

 plain. This plain is a remarkable feature of this part of the 

 mountains. A neaily flat expanse, chiefly of rock with a veneer 

 of arkose sand, but partly of alpine meadow sward, chilly, 

 featureless and desolate, it excited more surprise and comment 



