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aftershocks associated with the 1971 San Fernando earthquake on the San Fernando fault
zone which had a moment magnitude (MW) of 6.6 and local magnitude (ML) of 6.4. The

epicenter of the San Fernando earthquake was located approximately 611 miles northeast of
the project property (Figure 5), with a focus on the order of 8 kilometers deep (\Nhitcomb,
et al., 1973). Other historic earthquakes which may have caused significant strong ground
motion in the region include the 1857 Fort Tejon earthquake (Mw 7.9) on the San Andreas
fault, and the 1952 Arvin-Tehachapi earthquake (MW 7.5) in the southern San Joaquin

Valley. The 1952 Arvin-Tehachapi earthquake occurred along the White Wolf fault, or
possibly the Pleito thrust fault, and is approximately located at latitude 35 ‘ north, longitude
119 ' west, on the order of 40 to 45 miles from the project property (Figure 15). Numerous
aftershocks were also associated with this earthquake, as seen in the figure.

Most other historical seismic activity shown on Figure 15 is associated with faults and fault

zones located in the southern portion of the Great Valley, Los Angeles Basin, Transverse
Ranges, and central Mojave Desert. In the southern Great Valley, a cluster of earthquakes
shown to the northeast of the White Wolf-Pleito fault zone is located in the vicinity of
mapped races of the Kern Front fault, Kern Gorge fault, and Oilfields fault zone; some of
these may have been related to subsidence induced by oil withdrawal. Another grouping

of earthquake epicenters is in the vicinity of the intersection of the San Andreas fault,
San Jacinto fault and Sierra Madre fault zone. To the west and southwest, other clusters
of earthquake epicenters are located in the Los Angeles Basin area in the general vicinity
of faults such as the Whittier fault, Elsinore fault, Elysian Park fault, Santa Monica fault
zone, and the Newport-Inglewood fault zone.

7.2 POTENTIAL REGIONAL SEISMOGENIC SOURCES

Faults which historically have been the source of earthquakes or that show evidence of
displacement during Holocene time (the last 11,000 years) are considered to be active faults
by the State of California, Division of Mines and Geology. If movement during historic or

Holocene time cannot be demonstrated, but movement may have occurred during
Quaternary time (i.e., the last 1,800,000 years) the fault is classified as potentially active
(CDMG, 1973; 1980 revision). Active and potentially active faults located in the region
considered to have the greatest potential to generate significant strong ground shaking at
the project property are listed in Table 7 and shown on Figure 5. Other active and
potentially active faults located within approximately 60 miles (~100 km) of the project

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