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| Titel |
Modeling spatio-temporal variations of seismicity in the San Jacinto Fault Zone |
| VerfasserIn |
G. Zöller, Y. Ben-Zion |
| Konferenz |
EGU General Assembly 2012
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250063492
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| Zusammenfassung |
| We investigate spatio-temporal properties of earthquake patterns in the San Jacinto fault zone
(SJFZ), California, between Cajon Pass and the Superstition Hill Fault, using long records of
simulated seismicity constrained by available data. The model provides an effective
realization (e.g. Ben-Zion 1996; Zöller et al. 2007) of a large segmented strike-slip fault zone
in 3D elastic half space, with heterogeneous distributions of static/kinetic friction and creep
properties, and boundary conditions consisting of constant velocity motion around the fault.
The computational section of the fault contains small brittle slip patches which fail
during earthquakes and may undergo some creep deformation between events.
The creep rates increase to the end points of the computational section and with
depth. Two significant offsets of the SJFZ at San Jacinto Valley and Coyote Ridge
are modeled by strength heterogeneities. The simulated catalogs are compared to
the seismicity recorded at the SJFZ since 1932 and to recently reported results
on paleoearthquakes at sites along the SJFZ at Hog Lake (HL) and Mystic Lake
(ML) in the last 1500 years (e.g. Onderdonk et al., 2012; Rockwell et al., 2012). We
address several questions including the following intriguing issue raised by the
available paleoseismological data: are large earthquakes with signatures in ML and HL
typically correlated? In particular: is a typical paleoevent in HL an incomplete
rupture that is continued later in ML, and vice versa? The simulation results provide
insights on the statistical significance of these and other patterns, and the ability of
the SJFZ to produce large earthquakes which have not been observed in recent
decades. |
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