A mega-quake in America's second most populated city is due. 50-year-old buildings could come crashing down, killing thousands. Los Angeles will come to cinemas to see a blockbuster called San Andreas in which Los Angeles will be wiped out by an apocalyptic earthquake. Most of those in the audience will be wondering how long before it happens for real. The southern section of the San Andreas fault that runs near the city and has not had a huge earthquake of more than magnitude 7.5 since 1680. According to seismologists, an earthquake is more than a century overdue. Are southern Californian residents ready and prepared for a catastrophic earthquake?
"A big earthquake is inevitable," Los Angeles' said Dr Lucy Jones, a US Geological Survey seismologist, told The Telegraph. "Each earthquake that happens increases the probability. We know a lot about earthquakes, we know it will happen. We know everything but the time." Dr Jones is worried. She stays up at night because of the number of old concrete buildings that have not been retrofitted and could collapse into a pancake. The expensive retrofitting process involves reinforcing buildings, for example with steel braces. Weak earthquakes in recent months had me thinking on whether Los Angeles can withstand a major hit. In the first five months of 2014 there were five quakes of more than magnitude 4.0. The first time that has happened since 1994, sending jitters through Los Angeles. "LA was built in the 50s and 60s and all of the buildings from that time have some real problems," she said. Dr Jones herself would never live in one. According to a recent study by the University of California there are 1,451 concrete buildings that have not been retrofitted, including about 50 hotels, 50 churches, and 25 nursing homes. It has been estimated that 5% of these about 75 in total would collapse in a large earthquake. The question is which ones. "We are looking at what would happen in an earthquake and taking it all the way through to evacuation," said Dr Jones. "The problem with Southern California is we have 23 million people. Even if we were able to predict an earthquake in LA and evacuate, how many people would be killed on the freeways trying to get out?"
Since the 1980s many sensors has been installed. Including in a hole drilled a mile down into the San Andreas fault. According to the USGS the aim is to achieve a "better understanding of what happens on and near a fault during the earthquake cycle and to aid in predicting the time and severity of future quakes". "There's a lot of people scratching their heads and trying to come up with a method of prediction. It's a learning process," said Tim McCrink, a senior geologist with the California Geological Survey. The San Andreas is 30 miles away from downtown Los Angeles. Even an 8.0-magnitude quake on it would be expected to kill fewer people. It is estimated that would kill up to 18,000 people, make several million homeless, and cause up to $250 billion in damage. According to Dr Jones it would "hit all of downtown" which is stocked with concrete buildings that haven't been retrofitted. Such a quake on that fault is only likely to occur once every 2,500 years, but no one has any idea when the last one was. The USGS is doing a great effort to try to come up with warning system. Its now time the residents try to come up with their own evacuation plan.
Allen, Nick. "Los Angeles Awaits Earthquake That Could Be the 'Big One'" The Telegraph. Telegraph Media Group, 19 July 2014. Web. 04 Mar. 2015. <http://www.telegraph.co.uk/news/worldnews/northamerica/usa/10978030/Los-Angeles-awaits-earthquake-that-could-be-the-Big-One.html>.
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