Did the Earth Just Move?

I was just trying to get in touch with my sister, who lives in Michigan, to see if the earth had moved under her feet earlier today because of the earthquake in the Midwest. Although the Midwest is not known for earthquakes, one of the biggest faults runs through the middle of the country. This quake was a 5.2 with an epicenter near Evansville, Ind.

The news said that the earthquake could be felt as far as Michigan, but there were no reports of major damage even near the epicenter. Since it happened in early morning, about 5:30am EST, most people probably didn't even notice it.

It reminded me of the only two times I had been anywhere near an earthquake. The first time I was driving and did not find out about it until I got back to work at the hospital where I was a NM tech. Everyone there was saying they felt the earth move a little, but the vibrations of the car must have overwhelmed any small vibration. I was a little disappointed to miss the experience.

The other time, I was attending the Society of Nuclear Medicine Annual Meeting in San Francisco. I think it was in '87 or '88, and I was giving a scientific paper presentation.

My daughter (19 or 20 at the time) had come along with me and I took one afternoon off to take her to the Great America Amusement Park in San Jose, which was a bit of a way from San Francisco.

We had just gotten off the rollercoaster and were looking for souvenirs near the base of the coaster when there was a tremendous roaring noise. The building started shaking and stuff started to fall off the shelves. I thought, "Gee, that rollercoaster comes awfully close to this shop." It took a minute and a look at the panic on the shop assistant's face to realize that what I took to be a coaster was really an earthquake. It turned out to be a 6.2 quake located fairly close to the park. Luckily, it was in a rural area, and there was only some property damage and no casualties. I was glad I had already gotten off a ride, because many of the people were stuck on them for nearly an hour until it was determined that they were not damaged.

When I got back to San Francisco, I was expecting to see some damage but everyone I talked to there said they had barely felt it.

So, I suppose that an amusement park is probably the only place where you can be in a earthquake and not know it, because everything seems to be shaking and roaring all the time.