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Sep 17Liked by Judith A Hubbard

I don't see the eastern California events in this article, including Landers, Hector Mine, Ridgecrest or the ones just below the US border. I sees like those events may have reduced the stress in the southern San Andreas. Just wondering.

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Yes, those earthquakes were big enough to release some stress. However, because the earthquake magnitude scale is log-based-30 (i.e. a M8 releases 30x more energy than a M7, and ~900x more energy than a M6), they still don't add up enough to balance. All four of those earthquakes together were equivalent to one single M7.6. For comparison, the M7.8 and M7.6 in 2012 and 2013 offshore Canada and Alaska together released three times as much energy as that.

However, it is possible that some of the faults in California may more frequently release energy in the M7-7.5 range. A couple of earthquakes in that range have occurred along the Queen Charlotte-Fairweather Fault system in the last century - (1927 M7.3 M7.4 1970) - but more in California (1954 M7.3, 1992 M7.3, 1999 M7.2, 2010 M7.2, 2019 M7.1). Is this because of how distributed and irregular the fault system is in California? Or maybe it's just the irregular nature of earthquakes in these higher magnitude ranges - we're seeing one iteration of behavior, but it might be different for a different time window?

Whatever the cause, it is true that the southern part of the plate boundary has released more energy in the last century in M7-7.5 earthquakes than the northern part, but less in the M7.5+ range. The bigger earthquakes win out in terms of total strain release, but there are some interesting discussions to be had about how that works.

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I’ll be sure to let him know 😁

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Dutchsince latest earthquake forcast.

West coast to the east. Important information.

https://youtu.be/GddmsLmf__M?feature=shared

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These forecasts are not based in any scientific method and should be entirely ignored. Earthquakes cannot be predicted, or "forecast" in the way described.

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