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Comment by cortesoft | Hacker News Reader

Was giving my daughter a bath when it started. At first I thought I was fainting, because it was a really slow rolling motion like I was on a boat. Then noticed the shower door moving.

My daughter kept saying she wanted to go see the earthquake. I think she thought it was outside.

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Same about the fainting. I was standing in line at Target on the 4th, and I could have sworn I was gonna pass out there and then until the lady behind me asked if anyone else had felt that. Then I noticed the aisle signs swinging!

I always get the names of the different types of quakes confused, but this one was definitely a lot of long slow movement. I have felt some that were more like loud bangs and big jolts, but this one was just like being on a boat.

I wonder if the P Wave is what gave you that feeling.

These are surface waves, which have a much greater amplitude on the earth's surface than P-waves (which are faster). It's pretty unlikely that anyone can feel P-waves unless they are fairly close to the epicenter. P-waves are also basically a very short pulse; the S waves, which come later, last a bit longer, but also may have relatively low amplitude, and then the surface waves come last and cause the most perceptible (and damaging) ground motion.

http://www.geo.mtu.edu/UPSeis/waves.html

I definitely felt the p waves in the Seattle quake about 18 years ago. It felt like an initial whump, followed by the shear shaking a moment later.

I always look for liquid surfaces, water in a glass etc. They will be busy oscillating much before the body makes sense of whats going on...

Ah yes, the Jurassic Park method of shake detection.

> “The mirror shaking was easy … put a little vibrating motor in and shook it.” Lantieri said. “But the water was another story. It was a very difficult thing to do. You couldn’t do it. ”

> “In order to replicate that for the eventual shot, they “fed a guitar string through the car, down to the ground, and then I had a guy lay under the car and pluck the guitar string,”

https://www.businessinsider.com.au/jurassic-park-water-cup-2...

Wow, great anecdote hah I never would have thought that’s how they did it

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