64 SOUTHERN CALIFORNIA GEOLOGY 



What newcomer, who has seen its peculiar high- 

 lands and valley plains, its eccentric rivers, its de- 

 tached islands and its terraced coastlines, but has 

 wondered why such things are, as they are, so different 

 from features elsewhere seen. 



Although called a portion of the Pacific Province of 

 the great Cordilleran Region of the United States — 

 that newer, western half of our continent, so contrast- 

 ingly different and foreign to the older, eastern, or 

 Appalachian half — the State includes several distinct 

 sub-provinces, each of which is worthy of being con- 

 sidered as a geographic unit. 



Yes, all of California is different from the remainder 

 of the United States, from the New England and Ap- 

 palachian States, from the mid-continent plains and 

 prairies, the Rocky Mountains, or other regions. 

 Even within its bounds its several parts are different 

 from one another, and of these parts Southern Cali- 

 fornia is different from all the rest. It will be excus- 

 able in me to classify and briefly describe its divisions 

 in a manner somewhat unlike that which has hereto- 

 fore been done. 



CHIEF SUBDIVISIONS 



Including the Continental Shelf, the features of the 

 State may be broadly classified into six great groups : 

 (1) On the Desert Side, to the north, a portion of the 

 Great Basin Region whose further extent is eastward 

 into Nevada and Utah ; (2) to the south, on the desert 

 side the Gulf of California or Colorado Desert Depres- 

 sion; (3) features of the Great Transverse Belt — 

 mountains, ranges, valleys, highland plateaus and fault 

 line lineaments which extend east and west across the 



