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Did Earth's Twin Cores Spark Plate Tectonics?
Discovery News ^ | 06 Jan 2009 | Michael Reilly

Posted on 01/07/2009 9:20:26 AM PST by BGHater

It's a classic image from every youngster's science textbook: a cutaway image of Earth's interior. The brown crust is paper-thin; the warm mantle orange, the seething liquid of the outer core yellow, and at the center the core, a ball of solid, red-hot iron.

Now a new theory aims to rewrite it all by proposing the seemingly impossible: Earth has not one but two inner cores.

The idea stems from an ancient, cataclysmic collision that scientists believe occurred when a Mars-sized object hit Earth about 4.45 billion years ago. The young Earth was still so hot that it was mostly molten, and debris flung from the impact is thought to have formed the moon.

Haluk Cetin and Fugen Ozkirim of Murray State University think the core of the Mars-sized object may have been left behind inside Earth, and that it sank down near the original inner core. There the two may still remain, either separate or as conjoined twins, locked in a tight orbit.

Their case is largely circumstantial and speculative, Cetin admitted.

"We have no solid evidence yet, and we're not saying 100 percent that it still exists," he said. "The interior of Earth is a very hard place to study."

The ancient collision is a widely accepted phenomenon. But most scientists believe the incredible pressure at the center of the planet would've long since pushed the two cores into each other.

Still, the inner core is a mysterious place. Recently, scientists discovered that it rotates faster than the rest of the planet. And a study last year of how seismic waves propagate through the iron showed that the core is split into two distinct regions.

Beyond that, little is known. But Cetin and Ozkirim think a dual inner core can explain the rise of plate tectonics, and help explain why the planet remains hotter today than it should be, given its size.

"If this is true, it would change all Earth models as we know them," Cetin said. "If not, and these two cores coalesced early on, we would have less to say, but it could still be how plate tectonics got started."

Based on models of Earth's interior, Cetin thinks the two cores rotate in opposite directions, like the wheels of a pasta maker. Their motion would suck in magma from behind and spit it out in front. If this motion persisted for long enough, it could set up a giant current of circulation that would push plates of crust apart in front, and suck them down into the mantle in back.

Friction generated by the motion would keep the planet hot.

Scientists asked to comment on this hypothesis were extremely skeptical. Some asked not to be quoted, citing insufficient evidence to make a well-reasoned critique of the study, which the authors presented last month at the fall meeting of the American Geophysical Union in San Francisco.

"In terms of its volume, and even its mass, the Earth's inner core is quite small relative to the whole planet, about 1 percent," Paul Richards of Columbia University said. "I seriously doubt that inner core dynamics could play a significant role in moving the tectonic plates."


TOPICS: Astronomy; Science
KEYWORDS: catastrophism; core; earth; impact; jmarvinherndon; lunarcapture; lunarorigin; moon; tectonics; theia; themoon; thomasvanflandern; tvf; twin; vafirsoff

1 posted on 01/07/2009 9:20:27 AM PST by BGHater
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To: BGHater

Earth - With Dual Core Technology


2 posted on 01/07/2009 9:24:53 AM PST by Army Air Corps (Four fried chickens and a coke)
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To: BGHater
But most scientists believe the incredible pressure at the center of the planet would've long since pushed the two cores into each other.

The pressure at the center of the earth is just about zero. The geologists are smoking dope again.

ML/NJ

3 posted on 01/07/2009 9:26:52 AM PST by ml/nj
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To: ml/nj
The pressure at the center of the earth is just about zero. The geologists are smoking dope again.

I thought the pressure at the center of the earth is around a million times atmospheric. Are you confusing pressure with gravity?
4 posted on 01/07/2009 9:33:47 AM PST by ZX12R
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To: ml/nj
The geologists are smoking dope again.

Did they ever stop? Booze and dope are staples for Geologists, and I challenge any Geologist who has done a lot of fieldwork to claim otherwise.

5 posted on 01/07/2009 9:34:22 AM PST by HerrBlucher
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To: BGHater
and help explain why the planet remains hotter today than it should be, given its size

Silly scientists, everybody knows that's because of man-made global warming! AlGore told us so. The science is settled. Shut up.

6 posted on 01/07/2009 9:38:23 AM PST by NonValueAdded (once you get to really know people, there are always better reasons than [race] for despising them.)
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To: ml/nj

The pressure at the center of the earth is just about zero.

The gravity at the center of the earth will be just about zero (since the mass of the earth is approximately equally distributed in every direction. However, the pressure (from downforward in all direction from above) will be quite strong.

7 posted on 01/07/2009 9:46:16 AM PST by CaptainMorgantown
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To: ZX12R
I thought the pressure at the center of the earth is around a million times atmospheric. Are you confusing pressure with gravity?

I'm not confusing anything. Pressure is force (applied over some area). Where do you think the force comes from, PV=nrT?

ML/NJ

8 posted on 01/07/2009 9:47:20 AM PST by ml/nj
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To: NonValueAdded

This guy obviously is not part of the consensus!! s/


9 posted on 01/07/2009 9:49:24 AM PST by Iron head mike (I only watch porn because I like the music)
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To: BGHater
Haluk Cetin and Fugen Ozkirim of Murray State University

Go Racers!

10 posted on 01/07/2009 9:55:56 AM PST by Eagle Eye (Libs- If you don't have to play the rules then neither do we...THINK ABOUT IT!)
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To: ml/nj
"Results of the study of seismic wave propagation in the form of density distribution yielded a hypothetical pressure distribution model of the earth's interior. At the centre, the pressure is about 380 GPa (380,000,000,000 pascal)."

According to my calculations, that's about 55,100,000 PSI.
11 posted on 01/07/2009 10:02:29 AM PST by ZX12R
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To: ml/nj

Are you a hollow Earth guy?


12 posted on 01/07/2009 10:05:12 AM PST by DManA
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To: ml/nj

I thought that ‘PV=nrT’ is for gases.


13 posted on 01/07/2009 10:08:07 AM PST by chopperman
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To: DManA
Are you a hollow Earth guy?

No. But I do have science degrees in other fields. I've been asked a couple of times by geology professors (I like to sit in on geology classes.) to write a paper about this when I've discussed it with them, but I really don't know much about writing such papers and haven't done so,

ML/NJ

14 posted on 01/07/2009 10:14:17 AM PST by ml/nj
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To: chopperman
I thought that ‘PV=nrT’ is for gases.

It is. So maybe that's not the imagined source of the imagined pressure?

ML/NJ

15 posted on 01/07/2009 10:16:41 AM PST by ml/nj
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To: ml/nj

Could you explain your theory please?


16 posted on 01/07/2009 10:20:42 AM PST by DManA
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To: ml/nj

BTTT


17 posted on 01/07/2009 10:24:56 AM PST by thackney (life is fragile, handle with prayer)
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To: DManA

If you had a hollow earth, would gravity pull you towards the center of the sphere? Yes. I believe gravity would be highest at the center, so anything other than a singularity would feel tremendous gravitational pressure at the center.

So the question is would that pressure be any different in a non hollow earth? I don’t think so. Or maybe I am wrong? Would the center be an “anti” gravity peak effectively repulsive? Are objects attracted to the center of mass even if the center of mass is not in the mass?


18 posted on 01/07/2009 10:26:07 AM PST by LeGrande
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To: BGHater

I thought the force of the hypothesized collision basically liquidated the cores of both bodies allowing everything that didn’t become the moon to meld into the new Earth.


19 posted on 01/07/2009 10:34:23 AM PST by dead (I've got my eye out for Mullah Omar.)
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To: LeGrande

At every point in the sphere the force vector due to gravity is the sum of all force vectors acting on it. At the center are all the vectors add up to 0. Is this correct?


20 posted on 01/07/2009 10:46:27 AM PST by DManA
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To: DManA
Geologic pressure does come from gravity. For example the atmospheric pressure we observe comes from the weight of the air column above us. The matter at the center of the earth is surrounded by a uniform mass field and so the forces exerted on this matter are equal and opposite in all directions. It's really very simple. The thing that isn't so simple is that when we study gravitation we show that the gravitational field of any body acts as if all of it's mass were concentrated at its center of mass. And this may be true when that mass acts on something outside of itself, but it clearly is not true when considering gravitational forces within that body.

ML/NJ

21 posted on 01/07/2009 10:52:44 AM PST by ml/nj
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To: ml/nj

So, if I could curl up and occupy that ONE point at the exact center of mass, all of the forces surrounding me would be equal and opposite in all directions. Fair enough. Off by a micron or two, though, and I’m smushed!


22 posted on 01/07/2009 11:30:26 AM PST by Fredgoblu
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To: Fredgoblu
Off by a micron or two, though, and I’m smushed!

Hardly. You would be surrounded by approximately 4000 miles of matter whose non uniform density complicates the problem quite a bit, but the field of unbalanced matter would be relatively small and quite distant. Even being several miles off wouldn't matter.

ML/NJ

23 posted on 01/07/2009 12:03:51 PM PST by ml/nj
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To: DManA
At the center are all the vectors add up to 0. Is this correct?

They have to add up to zero.

So if we built a Dyson sphere with the mass of a black hole, at the diameter of an event horizon, would we still have a black hole? Would the sum of the gravity in the center of that artificial black hole be zero?

24 posted on 01/07/2009 1:00:56 PM PST by LeGrande
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To: BGHater
Did Earth's Twin Cores Spark Plate Tectonics?

I don't know. Isn't Al "the Boob" Gore using his vast intellect to tackle that pesky continental drift problem? I'm almost sure I heard something about a "plate shift" credit program.

25 posted on 01/07/2009 2:55:00 PM PST by MosesKnows (Love many, Trust few, and always paddle your own canoe)
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When the Days Were Shorter
Alaska Science Forum (Article #742) | November 11, 1985 | Larry Gedne
Posted on 10/04/2004 10:31:59 AM PDT by SunkenCiv
http://www.freerepublic.com/focus/f-chat/1234919/posts


26 posted on 01/07/2009 4:26:58 PM PST by SunkenCiv (https://secure.freerepublic.com/donate/___________First 2009 Profile update Tuesday, January 6, 2009)
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To: BGHater; 75thOVI; aimhigh; Alice in Wonderland; AndrewC; aragorn; aristotleman; Avoiding_Sulla; ...
Thanks BGHater.
 
Catastrophism
 
· join · view topics · view or post blog · bookmark · post new topic ·

27 posted on 01/07/2009 4:27:29 PM PST by SunkenCiv (https://secure.freerepublic.com/donate/___________First 2009 Profile update Tuesday, January 6, 2009)
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To: DManA

Hydrostatic vs shear stress.

A submarine that goes deeper than it’s rated depth shall implode, but not because of the difference in pressure between the upper and lower portions of the hull, but because the outside forces are greater than what the hull can resist.

For every force there is an equal and opposite force for systems in equilibrium, but nothing says the egg shaped earth has an equilibrium without dynamic changes in such a model. If the forces cancel each other at the center, this just means the center isn’t moving, but is in equilibrium.

If all the gravitational forces are acting upon each other, there might not be an acceleration, but the hydrostatic stress on that small volume still will be tremendous.

I thought the model of the interior core was one of a plasma.


28 posted on 01/07/2009 6:54:42 PM PST by Cvengr (Adversity in life and death is inevitable. Thru faith in Christ, stress is optional.)
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To: BGHater

If that’s true, then it’s another argument against the prevalence of extraterrestrial life. Without a molten core and magnetic field, the solar wind would rip Earth’s atmosphere away like it did on Mars and the planet would get bombarded with a lot more radiation. If it’s normal for planets to quickly cool down and lose their magnetic fields (like Mars, Venus, and the Moon), then extraterrestrial life, particularly intelligent extraterrestrial life, becomes a lot less likely. In various ways, the Moon has been credited for life on Mars but one of it’s biggest contributions may be the collision that formed it.


29 posted on 01/07/2009 8:01:45 PM PST by Question_Assumptions
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To: Cvengr; ml/nj

That sounds reasonable. You should be debating ml/nj


30 posted on 01/08/2009 1:57:45 AM PST by DManA
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To: ml/nj

Yes but to find the force acting on a point within the sphere you need to integrate the force vector field from the point to the surface. At the center of the sphere this will be a very large force.


31 posted on 01/08/2009 5:06:06 AM PST by DManA
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To: DManA
Why don't you suggest some equations instead of waving you hands? I'm really not certain what it is that you are saying.

ML/NJ

32 posted on 01/08/2009 5:34:37 AM PST by ml/nj
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To: ml/nj

If a 2.2 kg cube stands on a scale, it imparts about a pound of force due to the acceleration of gravity on the mass. If another 2.2kg block sits on top of the first the combined force is 2 lbs. As more and more blocks with the same mass are stacked the force increases. When the stack gets up to several dozen miles each additional block adds less than 1 lbs force because its distance from the center of mass causes its acceleration to decrease. But the weight on the scale is the sum of all the individual forces.

Now start at the top of the crust. A 2.2 kg mass of dirt exerts about a pound of force on the column of earth beneath it. Move in. A 2.2 kg mass of dirt underneath the first exerts about a lb of force on the column of earth beneath it. The two combined exert about 2 lbs of force. Repeat this exercise all the way to the center of the earth’s mass. The force exerted by each mass will vary, near the center this force will approach zero, but the total force is the sum of each individual mass.

Repeat this in all directions and convert that force to pressure and that is the pressure at the center of mass. Certainly much more than zero.


33 posted on 01/08/2009 6:20:53 AM PST by DManA
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To: DManA
I wonder if you have ever been in a cave. There's tons of rock above you but all you feel is whatever the atmospheric pressure is.

Go to someplace where a highway has been cut through the rock. At the bottom of the cut there is stone there with tons of stone above it withstanding all this pressure you want me to envision. You will be standing on neighboring rock that used to be under the same pressure before the cut was made. Maybe you can find a small piece to take home or maybe you will have to use a tool to chip a small piece you can carry. Bring it home and put it a vise. Once you subject the rock to real pressure it will almost certainly fracture, but it had previously survived all that pressure you talk about. Solids are not fluids.

I don't pretend to understand this particularly well but I don't think anyone does. In your little mind experiment where you have me add all the forces of all those 2.2 kg blocks down to the center of mass, you conveniently (for your view) have me stop right there. But why shouldn't I just keep on going and start accumulating all those equal and opposite force vectors once I pass through the center?

ML/NJ

34 posted on 01/08/2009 7:53:49 AM PST by ml/nj
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To: ml/nj

If we had a hollow earth then your cave analogy would be correct.

At the bottom of the road cut the stone is indeed withstanding the pressure of the rock above it. Why do you think they brace mine tunnels?

In my mind experiment I did not stop with the initial colunm summation.

“Repeat this in all directions and convert that force to pressure and that is the pressure at the center of mass. Certainly much more than zero.”

Start at the antipode of the point I began the first summation. Repeat the process. You have the same force bearing down from that direction too.


35 posted on 01/08/2009 8:03:43 AM PST by DManA
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To: NonValueAdded

The scientists are talking about the temperature of the Earth’s interior not the surface temperature!
We all know about man-made global warming!


36 posted on 01/11/2009 5:50:41 AM PST by platetectonics
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To: BGHater

The scientists are talking about the temperature of the Earth’s interior not the surface temperature!
We all know about man-made global warming!


37 posted on 01/11/2009 5:50:41 AM PST by platetectonics
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To: platetectonics

I didn’t think a sarcasm tag was necessary - I guess it was.


38 posted on 01/11/2009 2:09:56 PM PST by NonValueAdded (once you get to really know people, there are always better reasons than [race] for despising them.)
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To: SunkenCiv
Electrical Journey to Center of the Earth

Exerpt:

...But becoming aware of plasma changes everything. Because gravity can distort atoms and because pressure can preferentially "squeeze" electrons out of lower layers, rock can become susceptible to electromagnetic forces. Because plasma cables and sheets (i.e., electrical currents) have been detected flowing between Earth's magnetosphere and the surface, the circuit must close by passing through the Earth. Because magma is a liquid plasma, it will preferentially carry currents. Because electrical currents in plasma pinch into filaments and tend to form "double layers" (capacitor-like formations), the distribution of currents inside the Earth will be highly inhomogeneous. Electrical heating will cause temperature discontinuities in "lines and lumps." Electromagnetic forces between current filaments and between the layers of double layers will cause enormous and sudden pressure variations.

Why doesn't this show up in seismographs of earthquakes? Or does it show up, then go unrecognized because researchers have no concept of plasma behavior? No one has ever investigated how seismic waves act in different plasma conditions. The seismograph scrawls a single wavy line, but the geologist must interpret it according to a choice among several competing theories. With the awareness of plasma, seismographs no longer provide reliable--or even understandable--information about conditions at depth.

ELECTRIC EARTH.LINK

Satellites will update the gravity map of Earth

By BBC News Online science editor Dr David Whitehouse

A new gravity map of the Earth suggests that if you want to lose weight you should go to India, where the pull of gravity is slightly less than it is elsewhere on the planet.

You would be slightly less than 1% lighter there.

The gravity map has been prepared to help scientists plan the forthcoming Grace (Gravity Recovery And Climatic Experiment) satellites, to be launched in a few weeks.

New gravity map released

SOURCE

39 posted on 02/23/2009 3:01:58 PM PST by Fred Nerks (We've got to get him out of that White House!)
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Moon Has Iron Core, Lunar-Rock Study Says

Moon Has Iron Core, Lunar-Rock Study Says

40 posted on 10/16/2010 7:51:48 PM PDT by SunkenCiv (The 2nd Amendment follows right behind the 1st because some people are hard of hearing.)
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To: Fred Nerks
Astronomy Picture Of The Day : A Gravity Map of Earth | NASA | 11.13.01 | Robert Nemiroff (MTU) & Jerry Bonnell (USRA) | Posted on 11/13/2001 5:27:19 AM PST by callisto
Thanks again Fred Nerks.


41 posted on 04/02/2011 10:48:33 AM PDT by SunkenCiv (Thanks Cincinna for this link -- http://www.friendsofitamar.org)
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