138 SOUTHERN CALIFORNIA GEOLOGY 



able scarp lines of the desert side which heretofore 

 have not been mentioned or described. 



This lineament may be divided into three or four 

 segments of approximately equal lengths which may 

 be named as follows: (1) The Channel Islands seg- 

 ment; (2) the Santa Monica segment; (3) the Cuca- 

 monga segment, which follows the south side of the 

 east half of the San Gabriel Range, and (4) the Pinto 

 Mountain segment — a rift which follows a line past 

 the north side of the Pinto Mountains from the vicin- 

 ity of the Pipes, on the east side of the San Bernar- 

 dino Plateau, to the Colorado River. 



The lineament, although composed of several dis- 

 tinct members, practically constitutes a nearly con- 

 tinuous fault line of almost three hundred miles in 

 length, the displacements of which aggregate from 

 5,000 to 15,000 feet. The westernmost member of 

 the line, as is indicated by the closely-spaced con- 

 tours of the Sonic Depth Finder Map of the United 

 States Navy (See Plate I), follows the south side of 

 the Channel Islands from their western end to the 

 mainland. East of the islands it parallels the south 

 side of the Santa Monica Mountains from Point Muga 

 to near Santa Monica. From thence eastward to the 

 east end of the Santa Monica Range its course makes 

 the south fault scarp of these mountains as in the vi- 

 cinity of Beverly Hills, Hollywood and East Holly- 

 wood. It practically follows that part of Los Feliz 

 Boulevard between Western Avenue and the Los An- 

 geles River. This latter portion of its course consists 

 of several parallel faults. 



Details are lacking as to the course of the fault 

 through Tropico, Glendale and Ea^le Rock. More 



