Posts Tagged ‘Earthquakes’

Proud East Coast Earthquake Wimps

Yes, we streamed out of office buildings. We had some traffic jams. People pretty much freaked out because we’re not supposed to feel what we did today. It feels like everything is kind of shaky these days.

We barely survived the debt default scare, the financial downgrade and Wall Street’s convulsions. And now there’s a hurricane coming. So I was not the least surprised to feel the earthquake. If I am carried off by a swarm of locusts in the morning, I will simply accept this as the new normal.

It’s kind of interesting if you think about it. I mean how many generations of earthlings have passed before us- but we are the ones that get to see the end! Imagine being the first generation to not be able to tell our grand kids about all we went through- because we’ll be gone! So we just need to relax and watch this all unfold.

And we East Coast people are not complete, total wimps! Geologists say the rocks we sit on here in the East are kind of cold, dead things that allow the energy from an earthquake to spread really far without being dissipated. Here’s a Geologist who talked to the Washington Post. His name is Graham Kent. Dr. Graham Kent:

Even though it’s a 5.9, it’s a lot bigger deal than a 5.9 would be in California or Nevada. You might see damage further away from the epicenter than you might expect.

So there- you West Coast people who were laughing at us today. And you New England types who mock us, particularly in the Washington area, for closing schools when there’s an inch of snow—well, well….I guess you got us there.

Anyway…we are survivors here in ‘ol DC. We’re used to being hated for gridlock and taxes. Our highways rival LA and NY’s for their endless congestion. We don’t have a single escalator that works in our subway system. We have Augusts that compare to any horrible month anywhere in the world with miserable heat and humidity that will buckle your knees. We panic, have 9-hour traffic jams and crash into each other in winter storms. We haven’t had a sports team win a championship in nearly 20 years. What’s a little earthquake?

I laugh at earthquakes. The locusts, however, are going to be a little disturbing.

The Quake’s Effect on the Planet Earth

(Picture of Earth from NASA imaging devices on the Terra satellite)

You may have heard the rather astonishing fact that last weekend’s earthquake in Chile actually shifted the earth’s axis slightly- and literally shortened the Earth’s day by a small amount. Here’s the lowdown.

The shift in the axis due to the seismic event in Chile was approximately three inches. The change in the rotation of the planet effectively shortened the Earth day by 1.26 microseconds, slightly more than a millionth of a second. There’s no seismic or other event we know of that would lengthen the day, so we’ve pretty much lost that amount of day for good.

The guy who made these calculations is a fellow by the name of Richard Gross, a research scientist at NASA’s Jet Propulsion Laboratory. The axis he’s referring to is called the “figure axis,” not quite the North-South axis we usually think of, but close enough- they’re only offset by about 33 feet.

There was an even larger earthquake in 2004 in Sumatra that registered a 9.1, but the Chilean quake, though weaker, had a bigger effect on the axis because the Sumatran quake was nearer the equator while Chile’s was in the planet’s mid-latitudes, a location that offers a greater disruption of the axis, according to NASA. The fault that caused the Chilean quake also dips into the planet at a slightly steeper angle than the Sumatran fault and that also affected the Earth’s axis more.

For some reason my feeble civilian mind cannot understand, the Sumatran quake actually shortened the Earth day by 6.8 microseconds, five and a half times more than the Chilean quake, even though the trembler in Chile caused a greater movement of the axis.

What I do know is that over six years, between these two quakes, the planet’s axis has shifted half a foot and our once 24-hour day is now 7.26 microseconds shorter. This is not a quiet little planet.

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