I have a question about earthquakes. It seems like there have been an awful lot of big earthquakes lately. Is there some reason that they seem to be a lot recently? Like once one of the plates moves it somehow affects a lot of the other plates too. Or is it just a coincidence? I live very near the Hayward fault in the San Francisco bay area, so should I really start earthquake proofing my house and lab now?
We posed this question to Gopal Madabhushi from the University of Cambridge...
Gopal - Hello. This is (Gopal Marbushi). I'm a reader in geotechnical engineering at the University of Cambridge. It is true that large earthquakes have happened in close succession recently. For example, two larger plates in (c) Photo Marco Dormino/ The United Nations" alt="Port au Prince" />Christchurch in New Zealand and a very large earthquake in Japan. However, the fault systems in Japan and New Zealand are quite separate and there are no interconnections between them so, the earthquakes occurring together is a pure coincidence. Having said that, the two earthquakes near Christchurch may be interconnected, with stress release from one fault affecting the other. If you live in a seismic area, it is always better to consider earthquake proofing your house.
Diana - Earthquakes haven’t occurred anymore in the last 20 years than they have done over the last century, but we have far more seismograph stations and much better methods of reporting communication and accessible news. So, we’re being deluged with more stories about earthquakes which we know a lot more about. Plus, there are many more people in the world now who can be affected by such earthquakes.
I don't believe the absolute number of earthquakes, magnitudes, and etc have changed much over time. There certainly may be a reporting bias that we now hear of earthquakes in Malaysia, Haiti, Chile, and elsewhere that might not have made the news 50 years ago.
My guess is that whales are able to set off earthquakes by focusing their subsonic songs on the faults and structures which can move during a quake. The increased prevalence of earthquakes is coincidental to the decline in the whale population due to whaling and overfishing. grizelda, Sun, 5th Jun 2011
Have earthquakes been more frequent recently? If we are discussing recent history then one must say: "Yes, they most certainly have been".
2012, people. 2012. jimkingwood, Thu, 9th Jun 2011
In the advent of modern technology, minor earthquakes can now be recorded. This is not possible during ancient times, so the difference lies with the technology that is used to monitor these seismic waves. widereader, Wed, 21st Dec 2011
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