1. Physics‐Based Earthquake Simulations in Slow‐Moving Faults: A Case Study From the Eastern Betic Shear Zone (SE Iberian Peninsula).
- Author
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Herrero‐Barbero, Paula, Álvarez‐Gómez, José A., Williams, Charles, Villamor, Pilar, Insua‐Arévalo, Juan M., Alonso‐Henar, Jorge, and Martínez‐Díaz, José J.
- Subjects
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EARTHQUAKE simulators , *SHEAR zones , *EARTHQUAKE hazard analysis , *PALEOSEISMOLOGY , *KINEMATICS - Abstract
In regions with slow‐moving faults, the incompleteness of earthquake and fault data complicates the study of seismic hazard. The instrumental and historical seismic catalogs cover a short period compared with the long‐time interval between major events. Paleoseismic evidence allows us to increase the time frame of actual observations, but data is still scarce and imprecise. Physics‐based earthquake simulations overcome the limitations of actual earthquake catalogs and generate long‐term synthetic seismicity. The RSQSim earthquake simulator used in our study reproduces the earthquake physical processes based on a 3D fault model that contains the kinematics, the long‐term slip rates and the rate‐and‐state friction properties of the main seismogenic sources of a region. The application of earthquake simulations to the Eastern Betic Shear Zone, a slow fault system at southeastern Spain, allows the compilation of 100 kyr‐synthetic catalogs of MW > 4.0 events. Multisection earthquakes and complete ruptures of some faults in this region, preferentially on strike‐slip dominant ruptures, are possible according to our simulations. The largest MW > 6.5 events are likely as a result of jumping ruptures between the Carboneras and the Palomares faults, with recurrence times of < 20,000 years; and less frequently between the Alhama de Murcia and the Los Tollos faults. A great variability of interevent times is observed between successive synthetic seismic cycles, in addition to the occurrence of complex co‐ruptures between faults. Consequently, the occurrence of larger earthquakes, even MW ≥ 7.0, cannot be ruled out, contrasting with the low to moderate magnitudes recorded in the instrumental and historical earthquake catalog. Key Points: The RSQSim earthquake simulator reproduces a realistic 100 kyr synthetic catalog of MW > 4.5 events based on a slow fault systemLarge earthquakes, even MW ≥ 7.0, and complex multifault ruptures are possible despite their nonoccurrence in historical timesThe synthetic seismic cycles have variable interseismic time periods, so the different time frames should be considered in hazard studies [ABSTRACT FROM AUTHOR]
- Published
- 2021
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