MOUNT RAINIER NATIONAL PARK — An earthquake swarm at Mount Rainier that started on July 8 is considered one of the largest ever recorded for the volcano, according to the United States Geological Survey (USGS).
An earthquake swarm is a cluster of seismic activity or earthquakes that occur one after another.
So far, the largest earthquake in the swarm happened on July 11 and was no larger than 2.4 in magnitude.
By Friday, seismologists with the Pacific Northwest Seismic Network had located 1010 earthquakes.
They expect to locate more earthquakes from the data gathered during the swarm.
Mount Rainier is known to have about 9 earthquakes per month.
Swarms happen at Mount Rainier once or twice a year.
However, the previous swarms were smaller than the one that started on July 8.
The USCS reports that earthquake activity has slowed down from the 41 events per hour on July 8 to a few events per hour by July 25.
They say that any seismic activity after will be either noticeable or cause little to no damage.
USGS says that there is no reason to be worried about the earthquakes and that Mount Rainier remains at a color alert level of normal or green.
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