Ancient Imbalances Sent Earth's Continents "Wandering"

National Geographic News ^ | Continents "Wandering"

[blam]

[lesser_satan]

bump

[Centurion2000]

The theory states that at times Earth's surface mass becomes imbalanced. The continents become dramatically offset from the planet's spin axis and so move rapidly to right themselves

Excuse me while I call out for some skepticism. Crust 50miles thick. Mantle 2000+ miles thick. A defect on the skin of an onion is not going to destabilize the entire thing when it spins.

[beethovenfan]

Whatever it is, it’s Bush’s fault.

[spunkets]

Caption to go with the fig. in post 2...

"An illustration shows what Earth's continents looked like 110 million to 100 million years ago and their rotation based on magnetic signatures in ancient rocks.

A new study suggests that the motion represents a phenomenon called true polar wander, in which Earth's landmasses become imbalanced compared to its spin axis and then move rapidly to right themselves."

[aposiopetic]

A change like that today would put Richmond, Virginia, where Mexico City is now.

No, thanks.

Perhaps the Absolut Vodka people were just some frustrated geophysicist wannabe types.

[aruanan]

A new study lends weight to the controversial theory that Earth became massively imbalanced in the distant past, sending its tectonic plates on a mad dash to even things out.

Was this after the mass was ejected that formed the moon?

[spunkets]

"Crust 50miles thick."

The crust isn't 50 mi thick. It varies. Here's a contour map of hte thickness. 1km=0.62mi.

"This contour map of the thickness of the Earth's crust was developed from the CRUST 5.1 model. The contour interval is 10 km; we also include the 45 km contour for greater detail on the continents."

[Don Corleone]

All due to “Global Warming, Climate Change and anticipation of the Bush Presidency.”

[spunkets]

"Was this after the mass was ejected that formed the moon?"

Yes.

Mother Earth only started to spin later. It was an attempt to throw all the libs off into space. That didn't work. Next she tried shifting the land masses to dump them in the ocean as they slept. As we all know, they're still here.

[daku]

in other related news rosie o’donnells enormous girth contributed to hollywoods to lurch to the far left

[billorites]

"We use an updated global plate-tectonic reconstruction and integrate suitable paleomagnetic results from all continents," he said.

My chiropractor talks like that.

[USMA '71]

I read a good book many years ago about how the weight of the polar ice caps (not the tectonic plates themselves) caused the earth to change its polar orientation about every 7500 years. The poles would swing to the equator and cause quite a mess. It was called The HAB Theory and still has quite a following to this day. Just thought I'd share.

[enraged]

I guess I don't get it. It an object, say your clothes dryer is off balance, how does the heavier side migrate to the lighter side to correct itself? I can not think of another form of matter that actually self-repels from the force acting upon it. If we could repeat such an occurrence couldn't we duplicate it as a form of perpetual motion?

[RightWhale]

Einstein was interested in that hypothesis.

[Question_Assumptions]

Bump for later.

[The Great RJ]

St Algore, defender of mother earth, save us from the moving plates. (sarcasm)

[LiteKeeper]

It's called lot's of water, covering the whole earth...and then the water receding.

Check the Terra computer models at Los Alamos Labs!

[yefragetuwrabrumuy]

I can imagine a “jumpstart” being given to existing plate motion, say by the Chicxulub impact, a six mile diameter rock, producing a 100 teraton blast, leaving a crater over a hundred miles across.