72 SOUTHERN CALIFORNIA GEOLOGY 



age divide created between the valleys of the north 

 and the south by features of the Transverse Belt; 

 thus including the Santa Ynez Range, the Topa-topa 

 Range, the indefinite district which we herein call the 

 Piru divide or wilderness, and the Tehachapi Range 

 above mentioned. 



THE COAST RANGES 



The highlands of the western half of the Northern 

 California Region between the Great Valley and the 

 Ocean are the "Coast Ranges." They end to the 

 south along the northern side of the divide of the Santa 

 Ynez and Piru Creek drainage basins of the Transverse 

 Belt. This change is probably controlled by the Santa 

 Ynez fault line but in a manner too complicated to be 

 here described. We have tried to show on our outline 

 map the physiographic features of Southern Cali- 

 fornia. (See Plate 1.) 



The Coast Range highlands consist of a number of 

 long and narrow parallel ranges — the Temblor, Diablo, 

 Santa Lucia and San Rafael, separated by equally long 

 and narrow valleys, such as the Carrizo, Cuyama, 

 Salinas, Santa Maria, etc. 



These are the beautiful ranges which give individ- 

 uality to all the coastward side of Northern California, 

 and which adorn the environment of San Francisco 

 and other of its cities. They are largely composed of 

 the Franciscan rocks and the white, diatomaceous, Mon- 

 terey shales and brown, yellow and drab sandstones 

 and clay shales of Cretaceous and Tertiary periods. A 

 glance at their physical characteristics suggests that 

 they are a stage or more older than the ranges along 

 the coast of Southern California. Dr. J. P. Smith of 

 Leland Stanford, the dean of California paleogeogra- 



