I lived in the San Francisco Bay Area from 1987 to 1993, so I have felt some earthquakes. That includes the Big One, the 1989 Loma Prieta Quake, the most dramatic one that Northern California has experienced since the 1906 quake.
My undergraduate degree is in Earth Science and I tend to be more fascinated by quakes than afraid. Most people who have lived in California for a while tend to be pretty laid-back about quakes as well. But of course it depends on how big they are and how close you are.
If you are not so familiar with earthquakes, it’s hard to get a sense of whether you should worry or not! So this is a little overview that might help ease your fears about your friends and loved ones in California.
The USGS has a great summary of sizes of quakes and how they feel. It’s worth looking at to get a sense of what different size quakes feel like. The chart describes what an earthquake would feel like to someone near the epicenter, or ground zero, if you will. The further away from the epicenter, the less intense the quake.
Because California has so many earthquakes, building codes are such that most buildings are designed and built to withstand them. So for most, say for anything under a 6.0 and not occurring right under you, you will not have to worry about buildings collapsing or major damage. In other words, in the USGS chart, most of California will fare better than the average in that category.
When an earthquake hits other parts of the world that have older buildings, worry more. When one hits California, worry less. If one hits in an area where earthquakes are common, worry less: people tend to be prepared. If one hits in an area where they are less common, worry more.
It’s also good to know that earthquakes can feel different, even at the same intensity. Sometimes they feel like a quick shock all at once, and other times they rumble and rattle. Then there are some where it feels like the ground is rolling like waves. It depends on the quake, if it’s shallow or deep, and it depends on the ground and rock below your feet. I have a friend who was in the Marina district in 1989, and he said he surfed down Lombard Street.
If someone lives on fill from way back, worry more. If they live on engineered fill, meaning recently developed areas, worry less. If they live on hillsides that are prone to mudslides and it has been raining a lot, worry more. If they live on flat ground, worry less.
The media doesn’t help any, because they love to sensationalize. Even in 1989, the headlines showed this. Despite the wild ride I experienced on the 18th floor of the Clorox Building in downtown Oakland, when I got home to my house, built in 1988 on engineered fill on Bay Farm Island in Alameda, nothing was broken or damaged. Yes, most of the pictures were hanging crooked and the cat was hiding. The most amazing thing was, water had sloshed out of the toilet upstairs, so the house obviously did some serious shaking. Bottom line, they know how to build them in California.
By all means, check on your friends after an earthquake and let them know you are thinking of them! Just don’t get sucked into unnecessary fear and worry.
Hope this helps.
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Here’s the copy of the front page of the paper from the day after the quake, that hangs in my basement. FYI, the actual statistics from this source:
“This major earthquake caused 63 deaths, 3,757 injuries, and an estimated $6 billion in property damage. It was the largest earthquake to occur on the San Andreas fault since the great San Francisco earthquake in April 1906.”
It’s just days later and there has been an 8.2 quake in Chile. You might find this interesting:
meaningofstrife 