http://www.latimes.com/local/lanow/la-me-earthquake-san-jacinto-fault-20160610-snap-story.html
Deadly but little-known: Why scientists are so afraid of the San Jacinto fault
By Rong-Gong LIn II, Shelby Grad and Joseph Serna
June 10, 2016, 6:02 PM
The 5.2 magnitude earthquake that hit the desert southeast of Los Angeles on Friday was centered along the San Jacinto fault, which is one of the regions most active and potentially dangerous fault lines.
The fault runs through populated areas such as San Bernardino, Colton, Moreno Valley, Redlands, Loma Linda, Hemet and San Jacinto, as well as near Riverside, Rialto and Fontana. The epicenter of Fridays quake was in a more isolated area near Borrego Springs in eastern San Diego County.
The quake, which struck at 1:04 a.m., triggered more than 450 aftershocks but caused no major damage.
Experts have been warning for some time, however, that the San Jacinto fault while less well known than the San Andreas poses a major threat to the region.
"Because the San Jacinto fault cuts into the middle of the Inland Empire instead of the edge of the desert it cuts through a lot more people, Julian Lozos, a Cal State Northridge professor of geophysics, told The Times in March. There's just more people directly living on this fault."
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The San Jacinto fault is also remarkably long, spanning 130 miles, which may explain why Fridays temblor reportedly was felt from Santa Barbara to the Mexican border, said Egill Hauksson, a research professor of geophysics at Caltech.
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