Saturday, February 27, 2010

Urban Destruction from Earthquakes

In the wake of today's news that a magnitude 8.8 earthquake hit Chile, I found this image, published on Feb. 25th in The New York Times, even more interesting than the first time I analyzed it. Many of you may know that I am slightly obsessed with earthquakes and earthquake preparedness, especially now that we live in a seismic zone here in Casa Cali.

In the map above (created before the disastrous quake that hit Haiti last month), you can see the cities predicted to suffer major damage in an earthquake due to shoddy construction. There is, not surprisingly, a strong correlation with poverty and a lack of enforced building codes (the latter a sign of functional, organized government).

Port-au-Prince made it on the map, but in my opinion the prediction was conservative given what we now know as the utter devastation that occurred in that city. Obviously earthquake prediction isn't an exact science, so all the circles should be taken with a grain of salt.

That said, I find it extremely interesting that none of the Chilean cities made it to the map. Chile is a very seismic country, having registered the largest earthquake in registered history (magnitude 9.5 in 1960) as well as now the 7th-largest as well (tied with a 1906 quake off the coast of Ecuador). I know that Santiago's modern buildings are all constructed according to strict earthquake retrofitting guidelines, but the older buildings are not. Hopefully the map's predictions will ring true in this instance and Chile will be spared the massive loss of human life that one might expect with an 8.8 quake.

I also find it intriguing that other prime urban areas prone to big quakes aren't on the map, namely Mexico City, Los Angeles and San Francisco. An oversight, or a bit of encouragement??

1 comment:

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