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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."
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?
And the net result of those photons's gravitionation affects the Earth not a measurable amount. I don't have a calculator handy, but even the sunlight streaming toward the Earth only has an equivalent mass density of 1E-22 kg/m^3 fight over the surface. You can kind of tell that this isn't important because you never hear about anyone having to account for it. For example, NASA doesn't need to take this into account when plotting spacecraft trajectories. The distance to the Moon, which varies by a few Earth radii (out of an average of 62) is going to affect things a lot more.
Also, you're theory breaks down when you consider that the Earth gets more additional sunlight when it's closer to the Sun than it does from a full moon. Remember, the Moon is about as reflective as charcoal. Not a lot of light bounces off o it. And what is bounced off (of a smaller surface than Earth has to begin with) is sent off in a lot of directions, not just straight at the Earth.
I recommend we ban the tides.
Don't get me wrong, we will still be able to use the tides if we absolutely had to, I'm not saying that we ever would. I'm talking about banning them from the rest of the world.
[o]_O
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.