The Oct 26, 2015 earthquake in the Hindu Kush region of Afghanistan measured a 7.5 moment magnitude (MMs), roughly equivalent to 10.7 megatons of TNT, and left 260 dead and more than 1,800 injured. Just five months earlier in April a 7.8 earthquake near Nepal, India left almost 9,000 dead and more than 21,000 injured.
While the loss of life, immense property damage, and immeasurable suffering affected the world, these details touch me on a very different level. I see these pictures and wonder when that will be me – as a Los Angeleno, I live every day over the tremble of the Big One.
There are over 300 fault lines criss-crossing California, the most famous being the San Andreas. Running nearly 810 miles along the length of the state, the San Andreas forms one of the shifting boundaries between the Pacific and North American tectonic plates. As both plates are moving in opposite directions, the fault line is under tremendous pressure.
With each passing year, scientists become more and more concerned regarding the pressure between these plates, and along other fault lines. Kate Hutton, a seismologist from the US Geological Survey, predicted the destruction from a 7.8 quake in LA would see 50,000 injured and over 1,800 dead in a 2014 TheWeek article. That’s not even the worst of it. Seismologists are continually uncovering more information on the region and now feel a 7.5 quake along the Puente Hills fault line would result in a catastrophic 18,000 dead and $250 billion in damages.
Don’t even get me started on The Really Big One along the Cascadia subduction region north of California through the Pacific Northwest. Some scientists are looking to that zone as the crack which will tear off parts of Oregon, Washington, and western Canada.
So, ¿how worried should I be? Well, there’s the rub. Seismology is a very exact science dealing with extraordinarily complex and unknown factors. Predictions run the gamut, but some experts estimate an 80% chance for a major ~7MMs quake in the next 50 and and ~10% of a catastrophic (9+) in the same time-frame along these lines. These predictions are open to huge debate, but the one thing most of the experts agree: each year without a shift increases the tension and pressure; each year without a quake increases the magnitude of the next one when it comes.