In the News Question: At what point do earthquakes stop being “aftershocks” and become new events?
Is there a length of time that has to pass for a quake to be considered a new event, or just what is the criteria to stop calling them aftershocks?
Thanks.
I do believe this is how it works:
Aftershocks are those seismic events that occur after the initial event, and are smaller than the initial event. They are located over the same area as the initial rupture zone. Over time, as the earth settles, aftershocks decrease in frequency and magnitude.
If there is a larger earthquake that follows smaller earthquakes, the smaller ones would be considered foreshocks to the ensuing earthquake. But I think that really happens within a few days, and the more time that passes, the more likely that the first large earthquake was the main event.
I would imagine that once the earthquake event has been determined, all that follows would be aftershocks, and that the next earthquake to hit that fault or section of fault would be a looooong time coming.
Watch, some rock nerds are gonna probably thumb me down. All I ask is let me down easy.
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