Easter Sunday earthquake shifted Earth's crust nearly 3 feet near Calexico
The 7.2 Mexicali earthquake was so powerful that it shifted the Earth's crust up to 10 feet in Mexico, according to radar images and data released Wednesday by NASA.
The Easter Sunday quake also shifted the crust 31 inches near Calexico. The data for the California shift came from NASA satellites and those for the Mexican shift from European and Japanese satellites. Both sets of data were analyzed by NASA's Jet Propulsion Laboratory.
Eric Fielding, a JPL geophysicist, said shifts would be obvious in some places because the earth cracked. But the shifts generally occurred in remote desert and agricultural areas, so it's unclear whether people noticed the altered landscapes there.
The shifts are large, particularly for California, but they are not record-setting. The largest such "deformation" ever measured was 60 feet after the massive 9.5 earthquake that struck Chile in 1960, Fielding said. Along the coastline, places that used to be at sea level jutted up to 30 feet above the lapping water, he said.
The temblor, the largest to hit the Southern California/Baja California region in years, also increased the likelihood of earthquakes on faults north of the Mexican border, including the San Jacinto and Elsinore faults, said Andrea Donnellan, a JPL geophysicist.
However, she said it's too early to know which faults are more likely to rupture.
"This, combined with future measurements, will tell us how the region is changing and how" future earthquakes will behave, Donnellan said. "All these faults to the north had more stress added to them. We want to know which are more likely to break."
She added that the large Mexican quake probably reduced the chance of a temblor along some of the faults on the American side, though she said the focus right now is on which pose a greater danger.
The Elsinore fault runs through portions of San Diego County, including near Julian, Temecula and Lake Elsinore, according to the Southern California Earthquake Data Center. The San Jacinto fault runs near such cities as Hemet, Loma Linda and San Bernardino.
The Easter quake killed two people and collapsed numerous buildings in the Mexicali area. There was more than $90 million in damage in California alone, mostly in Imperial County.
The images used to measure the shift in crust were taken by the Uninhabited Aerial Vehicle Synthetic Aperture Radar, which is operated by JPL.
hector.becerra@latimes.coSource
More on yesterday's Canada quake HERE & HERE
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