Significant Earthquakes and Faults
Fault Name Index
Crafton Hills Fault Zone
Above, you can see the location of the Crafton Hills fault zone -- caught in a wedge between the San Andreas fault zone (in red), and the San Jacinto fault zone (in purple). Indeed, the Crafton Hills fault zone exists because of the actions of these two major faults. The sense of slip for both the San Jacinto and San Andreas faults is right-lateral. Thus, the area between the two, near the intersection, is being pulled apart. When this sort of extensional action exists, normal faults typically develop.