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Chili Earthquake & Earth's Rotation

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"The massive 8.8 earthquake that struck Chile may have changed the entire Earth's rotation and shortened the length of days on our planet, a NASA scientist said Monday. The quake, the seventh strongest earthquake in recorded history......"

Chili Earthquake & Earth's Rotation - do not use this link, Libby said it didn't work.

I want back and will re-post the link. Don't know what happened. Here it is again.

Chili Earthquake & Earth's Rotation

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  • Elders (Moderators)

Link doesn't work. Here's a link to the relevant bit on the NASA website: https://www.nasa.gov/...h-20100301.html

The Feb. 27 magnitude 8.8 earthquake in Chile may have shortened the length of each Earth day. JPL research scientist Richard Gross computed how Earth's rotation should have changed as a result of the Feb. 27 quake. Using a complex model, he and fellow scientists came up with a preliminary calculation that the quake should have shortened the length of an Earth day by about 1.26 microseconds (a microsecond is one millionth of a second).

Perhaps more impressive is how much the quake shifted Earth's axis. Gross calculates the quake should have moved Earth's figure axis (the axis about which Earth's mass is balanced) by 2.7 milliarcseconds (about 8 centimeters, or 3 inches). Earth's figure axis is not the same as its north-south axis; they are offset by about 10 meters (about 33 feet).

By comparison, Gross said the same model estimated the 2004 magnitude 9.1 Sumatran earthquake should have shortened the length of day by 6.8 microseconds and shifted Earth's axis by 2.32 milliarcseconds (about 7 centimeters, or 2.76 inches).

Gross said that even though the Chilean earthquake is much smaller than the Sumatran quake, it is predicted to have changed the position of the figure axis by a bit more for two reasons. First, unlike the 2004 Sumatran earthquake, which was located near the equator, the 2010 Chilean earthquake was located in Earth's mid-latitudes, which makes it more effective in shifting Earth's figure axis. Second, the fault responsible for the 2010 Chiliean earthquake dips into Earth at a slightly steeper angle than does the fault responsible for the 2004 Sumatran earthquake. This makes the Chile fault more effective in moving Earth's mass vertically and hence more effective in shifting Earth's figure axis.

Gross said the Chile predictions will likely change as data on the quake are further refined.

The Earth's axis changes naturally over time; that does have a slight effect because the Earth's tilt relative to the Sun makes a difference in terms of solar radiation at different lattitudes. I've been focussing more and more recently on understanding how all the different natural cycles affect this planet. I'm not particularly concerned about the effect of the Chilean earthquake on the Earth's axis - the effect on people living in that area is bad enough. But I am thinking about any possible effect on the ocean currents around that area in terms of any interaction between the plate tectonic activity there vis-a-vis the El Nino effect.

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Thanks Libby for watching my back and always for your input.

I have posted a new link and will again Here

Yes, the Earth's axis does change all the time naturally, but I'm concerned about what all mankind has done, and is still doing, to this planet that may have changed the natural course, like all the atomic, etc. bombs we've dropped, including under the ground and in the ocean. There may very well be areas that will be hit with a tidal wave sometime soon because Chili's earthquake was a real big one, "the seventh strongest earthquake in recorded history."

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