Covering earthquakes is getting to be a tiring, depressing business lately. From the horrific ongoing tragedy in Haiti that started with a magnitude 7.0 tremor in January to strong quakes in Japan, Taiwan, Chile, and just this morning, a magnitude 5.9 that killed 51 people in Turkey, the world appears to be cracking up with seismic energy.
But it isn't. At least, not any more than usual. Friends, let's be clear about this: the recent spate of dangerous earthquakes is emphatically NOT a run-up in seismic activity (despite what this blogger and this blogger think -- the comments sections of the second one is particularly chock full of nonsense).
This is just Earth doing its thing. Statistics from the United States Geological Survey show that around the world, earthquakes between magnitude 6.0 and 6.9 occur on average 134 times per year. Here's the list for all magnitudes:
| Magnitude | Average Annually |
|---|---|
| 8 and higher | 1 ¹ |
| 7 - 7.9 | 17 ² |
| 6 - 6.9 | 134 ² |
| 5 - 5.9 | 1319 ² |
| 4 - 4.9 | 13,000 (estimated) |
| 3 - 3.9 | 130,000 (estimated) |
| 2 - 2.9 | 1,300,000 (estimated) |
¹ Based on observations since 1900.
² Based on observations since 1990.
The USGS even has its own page explaining how the perceived increase is likely due to improving monitoring capabilities and instrumentation. I'd add that the globalization of media via the internet now means that we know immediately whenever a small town on the other side of the globe gets hit with an earthquake.
While there's no question that this morning's temblor in Turkey is a terrible tragedy -- and yet another warning to stay vigilant if you live in a seismically active area that has not had a quake recently -- it is merely the result of normal tectonic processes. It is not a harbinger of the End of Days.
Image: AFP
Tags: Earthquakes, Everyday Science, Geology, Geophysics, Natural Disasters
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