Swarm of More Than 250 Earthquakes in California Concerns Residents, Scientists

Scientists are keeping an eye on the California-Mexico border where a swarm of more than 250 small earthquakes have struck since New Year's Eve, the Los Angeles Times reported.

Heavy earthquake activity was detected in the southern end of the Brawley fault zone, a complex set of faults which stretches about 30 miles and is intricately connected to the Imperial fault zone. According to the Southern California Earthquake Data Center, the zone is prone to earthquake swarms "because of the complexity of the fault system at work."

But that has not eased scientists' and residents' concerns.

"There's always reason to be concerned for a bigger earthquake," Caltech seismologist Egill Hauksson told the Times.

The strongest earthquake during the swarm measured at 3.9, according to the Times. It struck directly under Brawley, a town about 200 miles southeast of Los Angeles. Scientists say it is important to keep an eye on the Brawley fault zone, as quake swarms that occur around the north end could trigger a major event on the San Andreas, the most famous fault in the world.

The San Andreas fault is due for an epic tremor and could rupture along with the San Jacinto fault, as it did 200 years ago.

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