Los Angeles given 5.0 quake warning

Los Angeles residents should brace themselves for a big earthquake, NASA has warned.


The space agency has said it is 99.9 per cent sure that LA will be hit by a 5.0 magnitude earthquake in the next three years.

It's basing its prediction on a study of the La Habra earthquake that shook Greater Los Angeles last year, according to the Daily Mail.

But in a rare public disagreement, the US Geological Survey (USGS) has said Nasa's analysis is wrong,
and there's only 85 per cent chance this could happen.

Donnellan explained that when the earthquake struck it relieved some of the stress in the fault system and shifted some of the upper sediments in the LA basin.

The earthquake was felt widely in Orange, Los Angeles, Ventura, Riverside, San Bernardino, Kern and San Diego counties.

While the earthquake was relatively moderate in size, the earthquake's depth, at 3.6 miles (5.85km),
combined with its location caused more than $12 million in damage.

Most of the damage occurred within a 3.7-mile (6km) radius of the epicentre of La Habra, with a substantial amount of damage south of the main rupture.

The team's results show that even moderate earthquakes near Los Angeles can produce ground deformation and damage to water mains away from their epicenters.

Using computer models, scientists found that the best explanation for the observed ground deformation was shallow movement along several active buried fault-like zone.

These included; the West Coyote Hills in northern Orange County; in the Chino Hills on the border of Orange, Los Angeles and San Bernardino Counties; and in the San Gabriel Valley.
It is likely the deeper portions of these faults remain locked and are capable of producing future earthquakes.

“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.”


Donnellan said a future earthquake to release the accumulated strain on these faults could occur on any one or several of these structures, which may not have been mapped at the surface.

But the US Geological survey is in disagreement with Nasa's results.

“The area — a 100 km radius circle centered on the city of La Habra — is a known seismically active area,' they said in a statement.

“For this same area, the community developed and accepted model of earthquake occurrence, 'UCERF3,' which is the basis of the USGS National Seismic Hazard Maps, gives a three-year probability of 85 per cent.

“In other words, the accepted random chance of an M5 or greater in this area in three years is 85 per cent, independent of the analysis in this paper.”

The disaster film, 'San Andreas', has put California's tremors in the spotlight over the past year.

The US Geological Survey has, however, previously warned the risk of 'the big one' hitting California has increased dramatically.

Researchers analyzed the latest data from the state's complex system of active geological faults, as well as new methods for translating these data into earthquake likelihoods.