3950 REPORT OF THE CALIFORNIA EARTHQUAKE COMMISSION. 
disturbance on this fault, have already been stated. Farther south, a fault runs parallel 
with the Salinas River in that portion of its course between Templeton and Dove; but 
here the apparent intensity was lower than in the valley lands both to the north and 
to the south. 
To the southwest of this is another parallel, but a longer fault, along the southwest 
side of the San Rafael Mountains. In the valley lands to the southwest of this, about 
San Luis Obispo, Edna, Arroyo Grande, and Santa Maria, the intensity rose from III 
to IV; but in view of the accumulation of evidence set forth in the preceding pages as 
to the influence exercised by alluviated bottoms upon the apparent intensity, this rise 
is more probably referred to the character of the ground than to proximity to this fault- 
line. South of Santa Maria is a region of frequent seismic disturbance, but no sharp 
shock of a local earthquake was felt there on April 18. 
It thus appears that in the territory extending from Humboldt County to Santa 
Barbara County, while there are about 40 faults known to geologists who have studied 
the region, there is no evidence of movement on any of them except in 3 cases. One of 
these is a branch from the fault-zone of the San Andreas Rift — the Black Mountain 
fault; another is a transverse fault intersecting the Rift in Pajaro Canyon; and the 
third is the fault which traverses the city of San Francisco and probably intersects the 
San Andreas fault beneath the Gulf of the Farallones. In these cases it is possible, in 
the light of the evidence, that some portion of the movement on the main fault was dis- 
tributed along intersecting faults. 
