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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."
"the force arising from changing the sea level by a couple of meters of water"
can you say "global warming"?
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 thought it was Sheep's bladders.
Objects in the blog are closer then they ap
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?
...a story about effects of el niño on earthquakes within the next 6 months.
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2B1ASK1
Sea water weighs about 60lbs. per cubic foot or so, right?
Considering that the Ocean is a few miles deep, that's obviously a lot of weight to shift around on top of the tectonic plates (which I assume are responsible for Earthquakes).
Don't think that a small group of dedicated individuals can't change the world. It's the only thing that ever has.
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.
Based on this research, it could easily be conjectured that the effect of global warming (which is causing the Polar Ice caps to melt) is also causing Volcanic activity.
As the Polar Ice caps melt, they add significant volume to [the] Earth(s) Ocean(s). The weight produced by this puts downward force on the tectonic plates. This downward force puts increased pressure on the magma beneath them, and the result is: Earthquakes _AND_ Volcanic activity (ala Mount St. Helens).
Don't think that a small group of dedicated individuals can't change the world. It's the only thing that ever has.
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
I lived in California for a while and survived both the '89 quake in San Fran, and the Northridge quake in LA.
Both of these quakes were preceded by what the locals all felt was "quake weather", a sort of 'strange heat and cold' combination that just seemed like it was building up pressure over the land. For days before Northridge, we'd been 'feeling like theres gonna be a quake', a sort of perception of the weather system.
Its interesting to see that tides affect the plates. I wonder if there's more research done on the 'quake weather' factor, even though its entirely a subjective observation, it really seems to me that there was a sort of 'on again off again' pressure-cooker weather system preceding both of those quakes.
; -- the corruption of government starts with its secrets. a truly free people keep no secrets. --
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.
But the polar ice-caps are already there - them melting wouldn't create any extra mass, it would just distribute it more evenly over the globe.
Just because you're paranoid doesn't mean there isn't an invisible demon about to eat your face
Not really. I was closer to the '89 quake than San Francisco was (at Ft. Ord), but we hadn't felt any magic weather around that time. And though I'm a Southern California native my wife, who was standing next to me as it hit, grew up in that area. And again, I'm a California native and have been paying attention to details back since I went through the '71 Sylmar quake.
The USGS, among others, has addressed this.
Generally, people reinforce either their feelings right after a quake, or remember the time they "felt" that weather just before one and forget the majority of the times they've "felt" that weather and no quake has happened
I would think that since the ice is at the poles, they do not have as much impact on the globe, with regards to tetonic stress. Now, they will figure into the equation. Think about spinning around with your hands at your side and then raising them, or better yet, just one. Same mass, different distribution. Big difference.
I prefer the "u" in honour as it seems to be missing these days.
In the form of ice caps, the mass of water doesn't move as much. Melting the ice caps would allow a greater mass of water to be shifted twice daily by the moon's tidal force.
I figure by 2030 or so my 6-digit UID will be something to brag about.
A comment I made just a few hours before this article posted mentioned moving the Moon into a geostationary orbit. This would eliminate lunar tides altogether; only solar tides, which are considerably smaller, would be left. To be sure, two sides of the Earth would experience very high stationary tides for a while (with corresponding low-low-low tides at 90-degree angles), until the Earth itself deformed sufficiently to cancel the effect, which probably wouldn't take more than a couple hundred thousand years.
I figure by 2030 or so my 6-digit UID will be something to brag about.
My actual (ex) father-in-law, Lowell, actually said, "Global warming is nothing but a conspiracy to raise my taxes." I laughed in his face, right in front of everyone in the restaurant. I am not making this up.
O~ Him that studies revenge keeps his own wounds green. -- Francis Bacon
There are differences between different individuals' amount of perception to various phenomena. One reason lots of subtle phenomena don't recur in the lab is the brain structure of the experimenters; they're analytical, and their conscious mind is totally ignoring what their gut is telling them, even though they're consciously trying to get it, they don't have the structures in their brains/nervsous systems to do it, no matter how bad they might want to.
O~ Him that studies revenge keeps his own wounds green. -- Francis Bacon
This is COMPLETELY wrong. The moon's gravity is not a function of its current reflectivity and phase, and has nothing to do with photons. What affects the tides is the relative orientation of the Earth and the moon/sun- whether the water is being pulled all in the same direction by the two bodies, whether there are two pulls at right angles... whether the pulls are working against each other, or in concert... But blaming reflection of photons? That's a whole load of scientific nonsense.
The World Wide Web is dying. Soon, we shall have only the Internet.
Well, my experience was different. In LA, my friends, my girlfriend, and I, had been talking about the 'quake weather' for the week before Northridge, and although I'd only been in San Fran for 2 weeks on business before the '89 quake, I still recall thinking 'quake weather' in the days preceding, not after
I lived in LA for 15 years. 'quake weather' was a pretty constant meme in those parts.. but hey, maybe my crowd were more generally paranoid than yours. Could be.
; -- the corruption of government starts with its secrets. a truly free people keep no secrets. --
The moon and sun exert tidal forces throughout the earth. Loose water sloshes about some, but the force works on rock, too.
It should be no surprise, in retrospect, that in places where plates are almost ready to move, a little nudge from tidal forces may induce an earthquake to start.
The rocks are straining and the sky gives them a little nudge.
what does "oh snap" mean?
I prefer the "u" in honour as it seems to be missing these days.