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Earth Tides Trigger Earthquakes
Dirak writes "UCLA scientists confirmed that Earth tides, produced by the gravitational pull of the moon and the sun on the Earth, causing the ocean's waters to slosh, can trigger earthquakes. There are many mysteries about how earthquakes occur, but now it is clear that it takes about the force arising from changing the sea level by a couple of meters of water to noticeably affect the rate of earthquakes."
This jives with the latest research that shows that most earthquake activity not related to volcanic activity occurs primarily during full moons.
A little background is probably necessary to explain that non-sequitor.
Einstein predicted that energy can have a gravitational field. This is a direct result of his calculations of General Relativity. Photons, though having no mass, have energy called quanta. Each quanta exerts a very small gravitational force due to GR.
During a full moon, more photons are emitted by the moon (reflected, actually) and thus the moon has a slightly greater gravitational pull during full moons than new moons (where it has very low gravitational force, relatively).
It's interesting to note that the last large earthquake in the Pacific Rim region was predicted to occur in California a month or two ago, but actually it occurred in East Asia, clear on the other side of the Pacific plate. Why? Well, the full moon was on that side of the world during night time causing large changes in the tides.
If this is true, this could lead to a breakthrough in earthquake prediction as well as damage minimization.
I must've learned in elementary school that earthquakes are caused by shifting plates of rock and earth below us...it seems a natural assumption to say that the power of the tides would have a great effect on moving said plates along. But i guess they needed some scientific proof.
Can anyone elaborate on my vaugeness, or make sense of what i'm talking about?
What most people don't know is that if the shaking lasted maybe 20 seconds longer it could have been the worst natural disaster in US history. The near failure of the Van Norman dam scared the bejeebers out of the Cal Department of Water Resources and they called for a lot of earth fill dams to be rebuilt.
A Shadeless room is a brighter room.
As a long time resident of the caribbean, I have always noticed that years we have large hurricanes (catigory 4 or 5) the amount of earthquakes in other parts of the world increase. The caribbean inlands sit on a fault line that is connected across Mexico to California and up to Alaska. One of our biggest Hurricanes in recent memory (Hugo in 89, Catigry 5) came 28 days before the big quake in SF. A quick Google search will come up with a few other coincedeces.. The other thing google found is the high amount of quakes in September, when during any given year we have 4 to 7 actve storms in the Atlantic, Caribbean, or Gulf of Mexico. Just a bit more food for thought...
Just Limin' Mon
In California, and in fact in most places in the world, the correlation between earthquakes and tides is considerably smaller, Vidale said. In California, tides may vary the rate of earthquakes at most one or two percent; the overall effect of the tides is smaller, he said, because the faults studied are many miles inland from the coast and the tides are not particularly large.