March 13, 2011

More unique perspectives of the 8.9 quake

Posted by Austin Elliott

As expected, videos continue to surface from people all over Japan documenting the shaking, rattling, and swaying of everything. Below I have collected some of the more interesting sights.

I recommend visiting Highly Allocthonous where Chris Rowan has summarized the which, what, where, and how of this massive quake. He’s also put together some nice little diagrams illustrating the more technical concepts.

The whole country of Japan shook for a very long time on Friday afternoon (their time). Beaches, farms, rural villages, forests, mountains, trains, and high-rise office or apartment buildings rattled for around two minutes while the plate boundary deep beneath them unzipped.

In Tokyo, the towering steel high-rises swayed with the low frequency waves passing through–a humbling sight from any perspective:

People’s responses to the shaking varied. This man has an understandably difficult time comprehending the emotional response of his neighbors. He’s alarmed at how much worse than the 7.2 foreshock two days prior this earthquake turns out to be. He runs outside into a cacophony of rattling structures:

This awesome video demonstrates Japan’s earthquake early warning system in effect. When the first seismometers in the country pick up the high-amplitude waves from this quake and determine its epicenter, an electronic signal is broadcast instantaneously, far in advance of the much slower seismic waves. This person has at least 30 seconds warning before the brunt of the shaking arrives. The shaking also gets worse and worse as it goes on–something many people would not be prepared for and anyone would find quite alarming.

In addition to informing people through the software shown in the previous video, the early warning system stops trains around the country to prevent derailment at high speeds. These folks are on one of the stopped trains when the waves start passing:

Here are some other videos I’ve stumbled across:

Other than the cameraman, these folks very aptly demonstrate the appropriate earthquake protection procedure while their apartment shakes heavily. On the other hand these fellows don’t seem to realize the import of the situation, although they appear to be only “gently” rocking in the upper stories of a building, like these office workers whose video doesn’t capture much apparent motion, but whose dialogue reveals the eerie sensation they’re witnessing.
In this video the quake rocks a 6th-floor bookstore.
Here we see the quake rocking a snowy temple, one that no doubt has experienced hundreds of these before. Watch the trees shake!
A shocked man sits helplessly in his car as the city trembles and the power goes out.
A transit station shakes noisily for a long time while commuters crouch to avoid being knocked off their feet.

In these videos it is indeed clear that despite extensive training drills, people are often overcome by the surprise and novelty of such a huge quake. In most cases, running outside is not a good strategy–imagine windows and cornices crashing down from the building you were in, or tiles sliding off the roof. Doorways are only safe to the extent that you can get yourself within a shear wall–your real security depends on the strength of the wall. Heavy, compact furniture is most often your best bet. Don’t let curiosity and surprise get the best of you!