THE EARTHQUAKE RIFT OF 1906 



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Earthquake Rift, as it comes up from the sea at Point Arena. Mendocino County. 



the Pacific, each earthquake rift follows the line of an old fault, and 

 the original break goes back to the mountain-making periods of Ter- 

 tiary times. The California earthquake of 1906 follows the axis of an 

 ancient break, the ' Portola-Tomales fault/ or ' San Andreas fault,' 

 first studied, so far as I know, by Dr. John C. Branner in 1892. In 

 this fault hundreds of thousands of earthquakes, large and small, have 



Fissure and Landslip, San Jacinto Valley, 1897. 



