The quakes were centered near Westmorland in the Imperial Valley, just southeast of the Salton Sea. That's roughly 180-200 miles southeast of Los Angeles and about 30 miles north of the Mexico border.
By 8 p.m. the USGS had recorded at least 240 quakes, with the largest hitting a magnitude of 4.9 at 5:31 p.m.
An #earthquake swarm has kicked off southwest of the #SaltonSea today, producing 240 earthquakes as of 8pm Pacific. The largest earlier this evening was M4.9.— USGS Earthquakes (@USGS_Quakes) October 1, 2020
So what does this mean? We’ve put together some scenarios to explain what could happen next. https://t.co/wMzKa8FKQM pic.twitter.com/ow9r7J5FH4
Seismologist Lucy Jones said the quakes are happening in the Brawley Seismic Zone, a network of small faults that connect the San Andreas and Imperial faults.
Historically, she said, the largest quake in that zone measured 5.8.
She said the zone is a common source of swarms and far enough from the San Andreas fault so that a quake closer to the Los Angeles area is not any more likely.
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