Earthquake Swarm in Long Valley Caldera Diminishes

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Over the past 42 hours, the earthquake swarm in California's Long Valley Caldera, which began last Friday (see September 26 post), has gradually diminished in terms of numbers of earthquakes and in earthquake magnitude.

At present, the rate of seismicity within the caldera is approaching background, with about 5 earthquakes between magnitude M1.0 to M2.8 occurring per hour. The swarm poses no immediate hazard. The USGS California Volcano Observatory will continue to track this activity and provide updates as appropriate.

Long Valley Caldera Earthquakes greater than M1.0 from 09/22 to 09/...

Long Valley Caldera Earthquakes greater than M1.0 from 09/22 to 09/28/2014.

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