Below the famous beaches, mountains and metropolitan areas of California is a sinister network of earthquake defects – some so sadly famous that their names are burned in the collective consciousness of the state.
There is, of course, the powerful San Andreas, whose massive shift caused the great earthquake of San Francisco in 1906 and whose notoriety has sparked several films, video games, books, t-shirts and collectibles.
The Newport -Entlectwood Faille is also well known in Los Angeles, which sparked the 1933 Long Beach earthquake – the deadliest Temblor in modern history of South California.
The large earthquake flaw near that which moved Monday morning in the mountains of the County of San Diego is however relatively obscure. But Elsinore’s fault is part of a larger seismic area than experts fear and believe that more people should know.
The Elsinore fault area is actually one of the largest in southern California, according to Caltech, but “in the historical era, was one of the quietest”.
However, this inactivity denies a devastating power. The fault is capable of generating an earthquake of magnitude 7,8, said seismologist Lucy Jones, Caltech research partner.
“Elsinore’s fault is one of the main risks in Southern California,” said Jones.
The Elsinore fault area goes from the Sonora desert in the county of Imperial through the western border of the Riverside county communities like Temecula, Murrieta and Lake Elsinore.
As he reaches Corona, he divides into two segments – the Chino fault, which goes to Chino Hills; And La Faille Whittier, which is near or bisette the suburbs of the county of the De Whittier, the Habra Heights, Hacienda Heights and Rowland Heights, and the Habra, Brea and Yorba Linda in the County of Orange.
A particularly frightening and plausible perspective would be an earthquake that rises the flaw of Elsinore to the northwest on the Whittier fault. This “would pour all the energy directly into the Los Angeles basin. This is one of the frightening earthquakes, “said Jones.
According to a hypothetical scenario published by the US Geological Survey, an earthquake of magnitude 7.8 in the Elsinore fault zone, including the Whittier flaw, could bring “violent” tremors – enough to damage the buildings strongly or even interrupt them of their foundations – on a relatively large area of Southland, including El Monte, Haceda Heights, Rowland Heights, Pico Rivera, Whittier, Whittier, Laba, Braus Linda, Placentia, Chino Hills, Corona, Lake Elsinore, Murrieta and Temecula.
It is a much larger area than the part of the San Fernando valley which saw “violent” tremor tremors during the Northridge earthquake in 1994, which was a magnitude 6.7.
“Serious” tremors – enough to reverse the chimneys and considerably damage the badly constructed buildings – can feel a little more distant from the broken fault, including in the city center of, East La, Long Beach, Alhambra, West Covina, Pomona, Ontario, Riverside, Downey, Norwalk, Santa Ana, Anaheim, Irvine and Lake Poret.
And “very strong” turning trends could be felt further, notably the San Fernando valley, the WeststSide, South Bay, the ports of Los Angeles and Long Beach, the Coast of Orange, Rancho Cucamonga, Fontana and San Bernardino.
No earthquake in modern times has been so powerful, or triggered such substantial and damaging tremors in such a wide strip of California.
The last 7.9 earthquake of the magnitude of southern California took place in 1857, when the San Andreas broke up between the counties of Monterey and Los Angeles. The last Temblor equivalent to Northern California was the great 1906 earthquake, which broke the counties of San Andreas between the counties of Humboldt and Santa Cruz and destroyed a large part of San Francisco.
Elsinore’s fault can be considered a brother or a sister of San Andreas, as well as the great fault of San Jacinto, said Kate Scharger, research geological geological survey. The San Jacinto fault zone begins at the Col de Cajon and moves south-east through San Bernardino and the County of Riverside before heading to the county of Imperial.
The three defects all move to relatively rapid rates on average – which means that everyone is, in general, more likely to break for the duration of a human life. San Andreas and San Jacinto move at an average rate of 20 millimeters a year, while Elsinore moves to a more modest clip of approximately 5 millimeters per year. On the other hand, the notorious of the Newport-Entlewood flaw moves much more slowly, at a rate of 1 millimeter per year.
“There is a risk that it is the next one,” said Scharger about the risk of a large on the Elsinore fault area. “We focus so much on the San Andreas, but we have all this follow -up of active defects that accumulate a constraint.”
Monday, magnitude 5.2 Temblor was a difficult reminder of the power of the fault. While the earthquake, which was centered near Julian, sent tremors to the region, there was no major injury or damage. But this may not be the case next time, especially if an earthquake is getting closer to major cities.
The Monday earthquake led to at least nine replicas of magnitude 2.5 or more, including a magnitude 4 a little more than an hour later.
The earthquake of magnitude 5.2 on Monday was preceded one day earlier from an earthquake of magnitude 3.3, which is now considered a preclusion.
The San Jacinto fault area is quite dangerous in its own right – passing through the heart of the inner empire, under many very populated areas. It is possible that the faults of San Jacinto and San Andreas could break in an earthquake of magnitude 7.5.
California is at a major risk of significant earthquakes because it is at the edge of a tectonic plaque border, where the Pacific plaque – on which San Diego, Los Angeles and Santa Barbara is located – slowly moves to the northwest compared to the North American plate, on which San Francisco is located, the central valley and the Big Bear lake.
This strain accumulates over decades and centuries, and is ultimately unleashed in the form of earthquakes around this tectonic plate limit.
Elsinore is a very long fault. The longer the break in an earthquake, the more the seismic energy is produced.
“The analogy is like an instrument – a little, small Kazoo, you cannot make it very strong,” said Sharger. “But if you arrive at an oboe … you can get a much stronger sound because it is a so much larger instrument, so more energy can mainly be pumped through this system.”
Some of the largest cities in California have made progress to demand that vulnerable seismic buildings be renovated, but vulnerabilities remain. A Times survey published in November revealed that a certain number of southern California suburbs had no active plans to demand buildings of fragile apartments, known as “sweet history”, to be renovated against earthquakes.
A particular dangerous place is the inner empire, where the brick buildings – a danger seemed so dangerous that them ordered them for fixed or demolished decades ago – is still a threat, despite the fault zones located under the region.
Another risk may be defective steel frame buildings, which must be modernized in a few cities, such as Torrance, Santa Monica and West Hollywood, but not in Los Angeles.
The counties of Los Angeles and Orange had little experience with earthly damaging earthquakes during the latest generation.
Since 1998, there has been only one earthquake of magnitude 5 or more under the counties of Los Angeles and Orange. It was an earthquake of magnitude 5.1 in 2014 centered on Brea, which caused more than 2.5 million dollars of damage in this city, Fullerton and La Habra.
There was also the earthquake of magnitula 5.4 Chino Hills of 2008. Centered in the county of San Bernardino, but just east of the counties of Los Angeles and Orange, it caused little damage.
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