Lawson.] 



The ( r pper Kern IUisih . 



'Ml 



higher than farther south, involving an upward tilting to the 

 north of this high system of ancient valleys. Such a tilling 

 seems to he indicated in the general falling away in the height of 

 the mountains southward of the latitude of Toowa Valley. The 

 writer at least has no serious hesitation in correlating the Little 

 Kern Plateau with the. Ohagoopa Plateau and Toowa Valley as 

 representing the same stage of the geomorphic evolution of the 

 southern Sierra Nevada. 



Former Connection of flic U'njh Valleys. — Recognizing the 

 synchronous evolution of Chagoopa Plateau, Toowa Valley, and 

 Little Kern Plateau, and the community of their relation to base 

 level, it is probable that, before they were lifted so high above 

 base level, they represented an interconnected system of drain- 

 age. What that connection was cannot here be positively 

 asserted; but certain suggestions are permissible in the way of 

 indicating possibilities. There are three possible outlets for 

 the ancient drainage of Chagoopa Plateau: (1) Northeastward, 

 by way of a pass at the head of Tyndall Creek, to the east of 

 Junction Peak, and thence either into the region of the present 

 Great Basin, or between Junction Peak and Mt. Keith into the 

 region of the present headwaters of the King's; (2) eastward 

 from its southern end by way of Toowa Valley or (3) southward 

 along the line of Kern Canon. The last of these seems to be the 

 least probable, since there is no definite remnant of a High 

 Valley terrace along the canon of the Kern below Volcano Creek. 

 The possibility of the Trout Meadows defile having been an 

 outlet is discussed later and rejected as improbable because there 

 is no evidence of its having been a stream trench, and because 

 it is lower than Little Kern Plateau and has, therefore, been 

 formed later than it. If the outlet had been originally to the 

 northeast by way of the pass at the head of Tyndall Creek, then 

 the uplift, which initiated the downcutting of Kern Canon, must 

 have deformed the region to the extent of reversing the general 

 slope of the country. As there is no independent warrant for 

 this supposition, and as the transitional slopes at the rear of 

 Chagoopa Plateau indicate a general southerly slope of the coun- 

 try at the time of its formation, this hypothesis cannot be 

 favorably entertained. The remaining possibility, an outlet by 



