Planet Earth may have 'tilted' to keep its balance

[Turtle]

By fluff I mean empty filler, bombasity, and breaking wind. Nothing short of a massive body could set this boondoggle straight on its axis. Fortunately there is truth in wine & children.

 

1) The term 'geographic poles' refers to the imaginary endpoints lying on the axis of Earth's rotation. The geographic poles are independant of any other reference.

2) The term 'true poles' refers to the points on the Earth's surface intersected by the axis defined by the geographic poles.

3) The term 'magnetic poles' refers to the N/S endpoints of the magnetic field generated by Earth. The magnetic poles have no fixed position, and their movement is measured against the position of the geographic poles.

 

With the above in mind, try re-reading the original article.

:QuestionM

[cwes99_03]

You just told me nothing. So did you carefully consider my posts, or is this for those other guys?

BTW reread your definition of geographic poles and true poles. You'll see that these points are one and the same, and that the earth's axis of rotation is exactly what I pointed out above in post number 9.

True poles (aka geographic poles) refer to the points on earth's surface where the axial line of rotation would intersect the surface of the earth.

 

The article above says that the earth rotates about this axial line and that this axial line may have tilted. It does not specify if the earth itself rotated anti-axially (about an axis orthoganal to its regular axis of rotation), thus keeping the geographic location of the true poles in the same place, or if the axis about which the earth rotates moved while the actual land mass of the earth remained stable (with respect to the plane of the sun's other satellites) but rotated about an axis pointed in a different direction.

[Turtle]

You just told me nothing.

So did you carefully consider my posts, or is this for those other guys?

BTW reread your definition of geographic poles and true poles. You'll see that these points are one and the same,

 

:doh:

:)

:esmoking:

[Turtle]

To clarify - yet again - the difference in the True Poles & the Geographic Poles.

The Geographic Poles are imaginary points on the imaginary line that marks the axis of Earth's rotation. The True Poles are the real points where the imaginary axis line intersects the Earth's surface.

 

The crust is floating on the mantle and composed of fractured plates, but it is only ONE floating crust. As it floats around, different parts of it intersect the opposite points where the imaginary axis line intersects the surface, and those points are the True Poles. While the Geographic poles remain in their orientation with no movement but precession, the moving crust passes different areas through this axis and the True Pole changes position over time.

While True Polar wander has been known in relation to individual plate movements (and their relation to Pangea & other super-continenets now known to have formed), this new discovery suggests that the ENTIRE crust moved as one, not individual plates.:hihi:

[cwes99_03]

That is not at all what I got from the article, or from the paper. I was under the impression not that they were simply talking about the "true" pole, as you have termed it, changing it's position because of crust movement (after all this has been theorized and accepted for years, but of the actual axis tilting due to a change in the mass distribution of the planet (thus an axial wobble).

 

This is a reasonable conclusion considering the opening words of Clay's article.

 

Imagine a shift in the Earth so profound that it could force our entire planet to spin on its side after a few million years, tilting it so far that Alaska would sit at the equator.

 

After all spinning on it's side would refer to the axis tilting to most people, not the crust moving and the side becoming the pole about which the planet rotates. This thought is supported by the idea that an unbalanced top will not shift it's weight around, but will change the axis of rotation until it doesn't wobble (or spins completely out of control).

 

Would someone like to more accurately detail the theory of "True Polar Wander"?

[Turtle]

That is not at all what I got from the article, ...

This is a reasonable conclusion considering the opening words of Clay's article.

 

Would someone like to more accurately detail the theory of "True Polar

Wander"?

Clearly you are having problems interpreting the article. While C1ay posted the article, he didn't write it, and yes the title is misleading. Nonetheless, the body of the article is clear on the point you raise issue with:

 

Though the poles themselves would still point in the same direction with respect to the solar system, the process could conceivably shift entire continents from the tropics to the Arctic, or vice versa, within a relatively brief geological time span.

 

Would you care maybe to more accurately understand the description(s)?:cup: Hang in there CW for the big "aha!":)

[cwes99_03]

OK, I'll wait for the aha, though I'm not sure if it is coming against the Princeton article or against me.

I read C1ay's article, and read the abstract of the princeton article.

So you say above that the princeton article says that the process could shift the continents enough so that alaska would now be at the equator (which is an imaginary line around the earth traced out by a line orthogonal to the axis) thus meaning that the axis itself did not rotate toward or away from the sun, but that the land mass itself moved.

I took it to mean that the axis would be tilted and the magnetic field about the earth would remain the same. And that due to axis tilt, the arctic would be facing more towards the sun during portions of the year and less during other portions, not that the equator would now cross the arctic.

 

Thanks, Turtle. I'm glad we finally came to an understanding here. I hope you realize that calling these comments fluff was not accurate, but I also realize where you came from in that we were not understanding the article.

 

Now I will reread the article from this standpoint and see what I can learn.

 

 

AHA!!!!

I caught the bit that I missed the first time I read the abstract. The very last line, which says:

 

depending on the continent's changing position relative to Earth's spin axis

[cwes99_03]

May I ask a question and not have it called fluff :cup: ?

 

Since I do not have a subscription to read the article, my question is as follows.

 

If the entire crust were to shift so that alaska is on the equator and say europe is now centered at the north pole:

1) how could all of the plates move in unison to accomplish this?

2) how rapid must this have happened, and how often, for these orthogonally layered magnetic striations to appear in the sediment?

3) what (and perhaps I just need to be reminded, because the answer doesn't immediately spring to mind) causes the earth's magnetic alignment, and why wouldn't this be somehow connected to the alignment of the plates.

4) Since this data, I'm guessing, comes from the same plate, what would deny the idea that a single plate rotated with respect to the magnetic poles thus causing the striation? (my guess is that this is seen all over the world in the sediment under the ocean, but then i thought this was theorized to have occured due to magnetic poles repositioning.)

[Turtle]

May I ask a question and not have it called fluff :cup: ?

That remains to be seen.;)

 

Since I do not have a subscription to read the article, my question is as follows.

 

If the entire crust were to shift so that alaska is on the equator and say europe is now centered at the north pole:

1) how could all of the plates move in unison to accomplish this?

I have no subscription either, but it's not necessary for any of the discussion so far. Apparently a super-volcano may move the plates all in unison.:cup:

2) how rapid must this have happened, and how often, for these orthogonally layered magnetic striations to appear in the sediment?

Millions of years according to the article.:)

3) what (and perhaps I just need to be reminded, because the answer doesn't immediately spring to mind) causes the earth's magnetic alignment, and why wouldn't this be somehow connected to the alignment of the plates.

The exact dynamics of the Earth's generating a magnetic field continue under study, however the source is deep in the core & lower mantle. The crust has no influence in generating the magnetic field.

4) Since this data, I'm guessing, comes from the same plate, what would deny the idea that a single plate rotated with respect to the magnetic poles thus causing the striation? (my guess is that this is seen all over the world in the sediment under the ocean, but then i thought this was theorized to have occured due to magnetic poles repositioning.)

The details of this analysis are in the paper, and they are anything but guessing.:lol: :hihi:

[cwes99_03]

I know they weren't guessing. I've seen a couple of other abstracts with their names on them.

 

Millions of years would not have created striations but a muddy puddle magnetically speaking. Striations in the magnetic alignment of the sediment would have to be reasonably sudden, and then maintained for a period to be noticeable. If it were regular every couple of years there wouldn't be a significant amount of sediment with similar alignment to measure and we wouldn't be talking about it.

 

Anyway, I'll look for the article somewhere where a subscription isn't required.

[Turtle]

Millions of years would not have created striations but a muddy puddle magnetically speaking. Striations in the magnetic alignment of the sediment would have to be reasonably sudden, and then maintained for a period to be noticeable. If it were regular every couple of years there wouldn't be a significant amount of sediment with similar alignment to measure and we wouldn't be talking about it.

 

Flufflier & fluffier.:cup: :)

[cwes99_03]

I think you're just playing with me {sniffle, tear}. :cup:

[Turtle]

I think you're just playing with me {sniffle, tear}. :hihi:

Like a Fox plays with a Mouse, Squeaky.;)

[Turtle]

Flufflier & fluffier.:doh: :doh:

 

Did I say fluffier!? I meant puffier.:hammer: :doh:

http://space.com/scienceastronomy/060914_cork_planet.html

[HydrogenBond]

Part of the evidence they are looking for are historical alterations in magnetic rock. This can also occur with the earth's magnetic field drifting during magnetic reversal, with the axis of rotation staying the same.

 

The idea of a large volcano causing the earth to shift its axis seems a little illogical. First of all, the material from the volcano came from underneath it on the very same position of the earth, so the latitude-longitude distribution of weight is exactly the same before and after. If the material came from Australia and teleported to Greenland, maybe. One may say it has to do with the change in the moment of inertia due to the height. I say, what about the Himalaya Mounts or even the Rockies? These are vertically huge in comparision and haven't done squat. The continental drift, collisions and upwelling didn't do anything either.

[silverslith]

The idea of a large volcano causing the earth to shift its axis seems a little illogical. First of all, the material from the volcano came from underneath it on the very same position of the earth, so the latitude-longitude distribution of weight is exactly the same before and after. If the material came from Australia and teleported to Greenland, maybe. One may say it has to do with the change in the moment of inertia due to the height. I say, what about the Himalaya Mounts or even the Rockies? These are vertically huge in comparision and haven't done squat. The continental drift, collisions and upwelling didn't do anything either.

 

It all depends on how deep the shear may have been. And the jury is still out on how deep in the mantle large scale vulcanism material comes from. Superplume theorists say very deep at the mantle-outer core boundary. 10-100m per year crustal shear is feasible on the outer layers of the mantle. The flood basalt eruption around 60million years ago in india is an example of enormous quantities of dense rock brought to the surface from most likely very deep. And it would have been replaced down there by isostatic forces. Some say this killed the dinosaurs. Personally I make the observation that it was at precisely opposite position to the central america meteor impact and may have been the result of the refocusing of seismic waves.

It helpful to look at plate tectonics as simular to the scum forming on the top of a simmering pot of stew. You can watch scum continents form, collide, and crack down the middle as their insulating properties cause heat build up in the middle. Supercontinents have formed and broken up repeatedly this way in the Earths ancient past.

The theory of "crustal displacement" is the same as what this article is proposing. The claim with that was that polar ice buildup could cause the crust to shear on the upper mantle and rotate until the previously polar regions were near the equator. Variation in the earths axis tilt are caused by external gravitational (and maybe magnetic) influence from other bodies in our solar system. A system can't change its overall rotational (or linear) inertia from inside itself.