Herding Cats
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Wow,have not heard that yet. I'm glad the Govenor issued that warning and didn't say all clear.
Question for anybody...when thre are large aftershocks like the initial one in Japan(7.something),why don't they create another tsunami? With all the aftershocks you would think it would just continue on. I'm glad it doesn't but curious why not?
I think the wave which hit HA was called a "wrap around", which means that the original wave hit one side, split into two (if there was nowhere to expend the energy, it has to go somewhere), and circled the island, and found less resistance on the far side, combined, and came ashore as an 11 foot wave. I haven't done enough oceanography to completely understand it, but that's my recollection of a potential issue with tsunamis and islands.
As to why they don't keep generating new tsunamis, they probably do. If you drop something into a container, you'll see the ripples hit the side, rebound, come back to the side, rebound. Each time, energy is lost, and the ripple is less.
If you consider the ocean as a big container, it's the same thing, although time is greatly different.
With earthquakes, most aftershocks are not "new" quakes - it's the land settling into a new position. Because of that, there isn't usually a "new" large displacement of land (which is the original "push" a tsunami needs to get going), and while there may be some undersea landslides, they probably are not big enough to disrupt the original wave pattern; perhaps add to it, in some way, but not disrupt it much.
If a new fault responds to new pressure, and a 'new' quake occurs, the whole sequence starts again. Depending on where it happens, it could be counter-energy that blocks the original energy, or complementary energy, which adds to the original energy.
That's as much as I know about it, and I only got a B in oceanography and plate tectonics...so I could quite easily be totally wrong.
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Herding Cats