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"Noon Boom" acoustic seismic signals recorded in the Long Valley Caldera, 11 March 2020

By California Volcano Observatory
A series of seismograms with lines showing the recorded motion of the ground at these sites in light gray. The measurements are ordered by distance from the source of the noise, with the closest at the bottom and furthest at the top. Darker, slanted lines show the speed that sound would travel in the air from that source to each of the seismometers, one for each burst, that line up with when the ground shakes. This example shows data from the Long Valley Caldera on 11 March 2020.
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Detailed Description

A series of seismograms showing acoustic signals from munitions detonations at the Hawthorne Army Depot. Signals were observed on 11 March 2020 in the Long Valley Caldera.

Sources/Usage

Public Domain.