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Los Angeles Alerted Before First of Two Earthquakes

A magnitude 4.4 earthquake hit Southern California, 25 miles from downtown Los Angeles, on Tuesday, Aug. 28, 2018. There have not been any reports of injuries or damage according to the U.S. Geological Survey.

The earthquake hit at 3:33 p.m. EST. The quake’s epicenter was three miles north of La Verne in the San Gabriel Valley.

Vickie Carillo, of La Verne, said it felt like the house was grabbed and shaken. She was watching “Jaws 2” with her son when the tremblor struck.

The earthquake was followed by a 3.4-magnitude quake approximately one minute later. Carillo stated, “We haven’t had an earthquake in quite a while – I mean not like that. I’m just glad I didn’t get in the shower like I was going to.”

Victor Flores said that the shaking was “extremely violent.” “It shook hard for what seemed like 10 to 20 seconds, and then it just kept going. It was really loud too, kind of like thunder. It just hit really hard and quick.”

A wide range of locations felt the initial quake as a sharp jolt near the epicenter or a rolling motion outside the epicenter. It shook downtown Los Angeles for several seconds. The jolt was felt 40 miles away in Sylmar to the northwest and 30 miles south in Huntington beach.

California has a nascent earthquake early-warning system and it had a successful run before the earthquake struck. According to seismologist Lucy Jones, the system sent out a warning three seconds before the earthquake was felt.

Earthquake Early-Warning System

The earthquake early-warning system is under development by the U.S. Geological Survey. It is only available to a limited number of testers. It is expected that more people will be eligible to test the system later in 2018.

The system has proven that it works. The alert gave officials a 10-second warning before a 5.3M quake struck Los Angeles in April.

The system works on this simple principle: The shaking from an earthquake travels at the speed of sound through rock. This is slower than the speed of current communications systems.

For example, it would take more than 60 seconds for a 7.8-magnitude temblor that began at the Salton Sea and traveled up the San Andreas fault. It shook Los Angeles 150 miles away. An early-warning system would allow L.A. residents crucial seconds, up to more than a minute to prepare.

According to the Los Angeles Times, “[The early-warning system] got a significant boost in the federal budget signed into law in March, defying an earlier proposal by President Trump to end federal funding for the program.”

Congress approved $22.9 million for the project. Last year, the project only received $10.2 million.

There has been a seismic early-warning system for the West Coast under development for years by the U.S. Geological Survey, however, the project has remained low on funds.

To complete a full system that would cover the West Coast would cost a minimum of $38.2 million and $16.1 million to operate and maintain annually.

The U.S. Geological Survey planned to issue limited public alerts from the system by the end of 2018. Southern California is an area where the network of seismic sensors is dense enough to register early warnings.

More sensors need to be installed in Washington, Oregon and in the sparsely populated areas of Northern California, for the system to go live across the entire West Coast. Currently, there are over 850 earthquake-sensing stations online, but according to officials, 800 more are necessary. Too few sensors could cause certain areas to experience a delay in the warning.

On the West Coast, airports, pipelines, oil refineries, universities, schools, libraries, and city halls are testing facilities for the system.

California hospitals are testing audible notifications, broadcast from fire alarm equipment, so hospital staff can take steps such as removing scalpels from patients in surgery.

There are some condominium towers that have tested the system. They have been similarly rewired to allow residents the time to drop, cover, and hold on before the earthquake strikes.

Additionally, some office buildings have been wired to take elevators to the nearest floor, preventing people from being trapped. Hopefully, the project will continue to receive the funding necessary to fully implement the early-warning system.

By Jeanette Smith

Sources:

Fox News: Earthquake east of Los Angeles hits magnitude 4.4, USGS says
Los Angeles Times: Earthquake early-warning system sent alarm 3 seconds before Southern California temblor

Image Courtesy of skeeze’s Pixabay Page – Creative Commons License

Los Angeles Alerted Before First of Two Earthquakes added by Jeanette Smith on August 31, 2018
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