In a new study led by NASA, JPL experts have predicted a possible magnitude-5.0 quake in Los Angeles, but have warned it could very well be stronger. The probability of this happening in the next three years, according to NASA, is 99.9%.
The team of researchers, led by Andrea Donnellan, a geophysicist at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, have studied the 2014 earthquake — centered in La Habra with a magnitude of 5.1 on the Richter scale. It was also revealed “the earthquake deformed Earth’s crust across a broad region, encompassing the northern Los Angeles Basin and northern Orange County.”
“The shallow ground-movements observed from this earthquake likely reflect strain accumulated on deeper faults, which remain locked and may be capable of producing future earthquakes,” JPL wrote in a statement.
The team of NASA and university researchers measure surface deformation in the Earth’s crust — which was caused by the March 28, 2014 earthquake — by using GPS and NASA airborne radar data. The researchers had found that the earthquake had deformed the Earth’s crust across a broad region, but mostly south of the main rupture, consistent with the observed damage, NASA wrote in a news release.
“The study builds upon more than two decades of NASA-led research to develop new methods to better measure and monitor movements of the solid Earth, using satellite and airborne data and advanced computer modeling,” Donnellan said.
“It also provides a means of using these technologies to identify which faults moved during earthquakes, to measure exactly how much Earth’s surface deformed during earthquakes — and to use these measurements to estimate future earthquake potential.”
The study shows “that even moderate earthquakes near Los Angeles can produce ground deformation and damage to water mains away from their epicenters,” JPL reported.
“The earthquake faults in this region are part of a system of faults,” said Donnellan.
“They can move together in an earthquake and produce measurable surface deformation, even during moderate magnitude earthquakes.
This fault system accommodates the ongoing shortening of Earth’s crust in the northern Los Angeles region.
A future earthquake releasing the accumulated strain on these faults could occur on any one or several of these fault structures, which may not have been mapped at the surface.
“Identifying specific fault structures most likely to be responsible for future earthquakes for this system of many active faults is often very difficult,” Donnellan said.
“Magnitude-5 earthquakes are to be expected not infrequently,” USGS seismologist Susan Hough told ABC 13.
“We don’t know for sure that something is going to happen in the next year or the next three years. That’s really overstating the case.”
The study was published in the journal Earth and Space Science.