There were about 250 small earthquakes in the swarm that hit areas around the California-Mexico border over the New Year weekend. Although most were so small that they were barely felt by the residents, the event is causing considerable concern throughout the state.
According to a report from LA Times, the largest one was only at a magnitude of 3.9. It hit the town of Brawley that's roughly 170 miles southeast of Los Angeles.
The first one - only at a magnitude of 1.1 - also occurred in Brawley at about 3:30 a.m. local time on December 31, Saturday, a report from RT revealed. Aftershocks were counted at over a hundred within the morning.
The earthquakes were concentrated south of a 30-mile seismically active region called the Brawley Seismic Zone, which actually connects two well-known faults: San Andreas and Imperial. Both are famous for being the site of relatively damaging earthquakes.
"This area may have produced the most earthquakes in the entire state of California, but they are small," Caltech seismologist Lucy Jones told CNN. "If they happened a mile away we would be concerned, but these quakes are about 30 miles from the San Andreas Fault."
Earthquakes in the state of California are quite a regular occurrence, although many remain unfelt by the general public.
"There's always reason to be concerned for a bigger earthquake," Egill Hauksson, another Caltech seismologist, added in the LA Times report. Because of the potential for disaster, Hauksson monitored the swarm since it started. By the evening of Sunday, the likelihood of the swarm causing a magnitude 5 or higher quake dropped significantly.
Just last December 28, Wednesday, a swarm of over 200 small quakes also shook up the California-Nevada border, according to a separate report from LA Times. A pair of magnitude 5.7 earthquakes started off the swarm in the early morning in the town of Bodie.