Moment Released by Aftershocks
نویسنده
چکیده
In constructing moment-balanced fault rupture models for the SF Bay region, WG99 needed to account for all the moment released by earthquakes in the region. These include earthquakes on characterized rupture sources, earthquakes on other rupture sources (background), and their aftershocks. Some of the aftershocks will be large, with magnitudes sometimes exceeding 6.7. WG99 assumed that an aftershock of this size would likely break the surface and have a rupture area comparable to one of the characterized fault segments, a fault segment in the background, or one of the floating earthquake sources. These aftershocks probably cannot occur on the same segments that broke in the main shock because they release too much moment. An aftershock of this size is often referred to as a triggered earthquake.
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