QT Early Warning System

San Andreas Fault
From a report this week by the Bulletin of the Seismological Society of America regarding the San Andreas Fault:
“. . . .Estimates of fraction locked, the ratio of moment accumulation rate to loading rate, on each section of the fault system provide a uniform means to inform source parameters relevant to seismic-hazard assessment. From its mean creep rates, we infer the main branch (the San Andreas Fault) ranges from only 20%±10% locked on its central creeping section to 99%–100% on the north coast. From mean accumulation rates, we infer that four urban faults appear to have accumulated enough seismic moment to produce major earthquakes: the northern Calaveras (M 6.8), Hayward (M 6.8), Rodgers Creek (M 7.1), and Green Valley (M 7.1). The latter three faults are nearing or past their mean recurrence interval.”
For those who wonder how geophysicists go about saying: “Uh-oh.”

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