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Pangea Ultima: Earth in 250 Million Years? (APOD 22 Sep 07)
Posted: Sat Sep 22, 2007 4:27 am
by craterchains
And, this is astronomical? Well, what ever, it is about earth in a far distant future!?!? uh huh, , ok, any comments?
ooops, sorry, I forgot the URL, , ,
http://antwrp.gsfc.nasa.gov/apod/ap070922.html
Posted: Sat Sep 22, 2007 4:40 am
by l3p3r
Posted: Sat Sep 22, 2007 8:22 am
by adrianxw
And, this is astronomical?
You beat me to it! I was about to post a similar comment. Yet another Earth centric "picture", appears on
Astronomy picture of the day!
Not even a picture, a projection based on one guys theories. Theories I find questionable. He says the North and South Atlantic Oceans will shrink due to subduction of the oceanic crust along the East coasts of North and South America. In fact the Atlantics are spreading, and there are no subduction zones on the East coasts of those continents.
Rather, The Pacific is being subducted around much of it's rim, (Pacific ring of fire), and in the cases discussed here, the WEST coast of South America is subducting the Pacific giving rise to the Andes mountain range.
Posted: Sat Sep 22, 2007 12:13 pm
by orin stepanek
Re: Pangea Ultima
Posted: Sat Sep 22, 2007 1:19 pm
by Case
Not hindered by in-depth knowledge of paleogeography,
isn't it more likely that the Earth's surface is stabilizing
thereby limiting how much tectonic plates will shift in the future?
It seems to me like the map is expecting shifts to keep going
until landmasses are re-aligned in a second unified big super continent.
While that would seem to give a nice sense of order,
it might violate the second law of thermodynamics;
things that break apart, usually don't realign by itself in the future.
All that shifting around costs energy,
which would position the plates to a more 'efficient' location,
until an equilibrium is achieved
where the plates don't move anymore.
I think that could very well happen long before a second alignment.
Posted: Sat Sep 22, 2007 1:29 pm
by BMAONE23
I'll need to spend a little more time on the links but I find it interesting that with the currrent tectonic movements (North America plate moving north and west over the Pacific plate) (the istmus of Panama being stretched as North America and South America are slowly pulled apart) (The Mid Atlantic ridge causing the Americas and Africa to expand away from each other) I just dont see how the Atlantic disappears, how the Americas and Africa join back along the mid atlantic ridge, nor how North and South america join again. What reverses the current motion?
Posted: Sat Sep 22, 2007 1:37 pm
by FieryIce
Comment? No
Why would I comment on a theory that spans “250 million years from now” when time frames of millions of years is stretching logic from meaningless to ridiculous.
Nereid had recently chastised posters about theories since theories are not part of the “only game in town” but since Robert Nemiroff (MTU) & Jerry Bonnell (USRA) out rank a Nereid then I guess theories are back on the menu boys.
I would be more concerned with “APOD editor to review best space pictures in Philadelphia on Wednesday” when clearly the editor for APOD September 22, 2007 didn’t distinguish an Earth Picture of the Day from an Astronomy Picture of the Day.
Posted: Sat Sep 22, 2007 2:38 pm
by Vulpine
adrianxw wrote:And, this is astronomical?
Not even a picture, a projection based on one guys theories. Theories I find questionable. He says the North and South Atlantic Oceans will shrink due to subduction of the oceanic crust along the East coasts of North and South America. In fact the Atlantics are spreading, and there are no subduction zones on the East coasts of those continents.
Rather, The Pacific is being subducted around much of it's rim, (Pacific ring of fire), and in the cases discussed here, the WEST coast of South America is subducting the Pacific giving rise to the Andes mountain range.
I agree. Most geological discussions I have read about Pangea say that this image is more like 250Million years in the past and that the Atlantic Ridge is moving the continents apart at something like 6" per year. The means logically that the Pacific ocean will eventually be nonexistant and the Atlantic will be the world ocean, probably developing a new continental landmass once the plates stop moving apart and the vulcanism is forced to go up instead of pushing out.
Of course, thinking about the Pacific Rim and the Ring of Fire, chances are the new Pangea is going to be extremely volcanic and otherwise geologically active when that happens. Probably end up with a mountain range that makes the Himalayas look small.
People really need to look at the broad view and collate all the data we have in a wide area of science to get an idea of where the world is going. The evidence is in front of our faces; the pieces just need to be put together.
Posted: Sat Sep 22, 2007 2:59 pm
by FieryIce
Vulpine wrote:People really need to look at the broad view and collate all the data we have in a wide area of science to get an idea of where the world is going.
Which from the sciences turns out to be at best, speculative.
Vulpine wrote:The evidence is in front of our faces; the pieces just need to be put together.
True
Posted: Sat Sep 22, 2007 5:34 pm
by Qev
Scientists detect what appears to be the beginnings of a major subduction zone forming along the east coast of North America through seismological modeling of the area.
If it forms, then it could very well subduct the mid-Atlantic ridge, causing the closure of the Atlantic Ocean. Yes, this is somewhat speculative, but it is founded on decent science.
And hey, Earth is a heavenly body too, yaknow.
![Smile :)](./images/smilies/icon_smile.gif)
Re: Pangea Ultima
Posted: Sat Sep 22, 2007 5:40 pm
by Qev
Case wrote:Not hindered by in-depth knowledge of paleogeography,
isn't it more likely that the Earth's surface is stabilizing
thereby limiting how much tectonic plates will shift in the future?
It seems to me like the map is expecting shifts to keep going
until landmasses are re-aligned in a second unified big super continent.
While that would seem to give a nice sense of order,
it might violate the second law of thermodynamics;
things that break apart, usually don't realign by itself in the future.
All that shifting around costs energy,
which would position the plates to a more 'efficient' location,
until an equilibrium is achieved
where the plates don't move anymore.
I think that could very well happen long before a second alignment.
Thermodynamics don't work like that, I'm afraid. It doesn't deal with 'order' as we perceive it, but rather with the amount of 'useful' energy in a closed system. Thermodynamically speaking, a shuffled deck of cards is just as ordered as a deck of cards sorted by suit and value.
While the amount of energy driving plate tectonics should be expected to decrease over time as the Earth continues to cool, it says nothing about the final disposition of the continents themselves, only that they should eventually stop shifting.
Pangea Model is not acurate
Posted: Sat Sep 22, 2007 7:00 pm
by andywyndom
Check this link out. It appears to make more sense to me.
http://www.nealadams.com/nmu.html
Posted: Sat Sep 22, 2007 7:27 pm
by Dr. Skeptic
This conception could be helpful to those who plan on time travel into the distant future, one might want to recognize the home planet.
I have also read that the centre of the North American continent is resting on unnaturally high hydrostatic pressure from the magma below. Before 250 M years, northern U.S. and eastern Canada will have drop one to two hundred meters become part of an enlarged North Atlantic.
Re: Pangea Model is not acurate
Posted: Sat Sep 22, 2007 9:20 pm
by Case
Pretty neat, quite convincing. It would be nice to address the reason for the growth, tho'. That seems to be missing from his presentation.
an enlarging earth
Posted: Sat Sep 22, 2007 9:28 pm
by jimsaruff
Say, Andy;
Nice link to the 'expanding earth' videos. One question I have is: isn't the earth being 'measured' from satellites already? Aren't there reports of the various continents moving by fractions of inches each year?
OTOH, wouldn't it be great if an enlarging earth were responsible for the unexplained weight loss of the International Kilogram (stored in Paris, I believe)?
In fact, couldn't someone mathematically find that the 50 microgram (working on memory here) weight loss could have resulted from some definite greater radius of the earth?
Well, I realize this doesn't seem to be astronomy. As far as I am concerned, technically, we just happen to live on an astronomical body.
Hope everyone is having a nice day out there.
Posted: Sun Sep 23, 2007 12:38 am
by BMAONE23
It could lend credence to the expanding universe theory, "Everything expands exponentially."
But........Where does the "New Material" come from that allows for the expansion.
Plate tectonics explains things better in that material is subducted from the pacific plate, melted under the north american plate, and extruded in the Mid Atlantic ridge forcing the plates there to expand thereby causing the north american plate to subduct the pacific plate........
Posted: Sun Sep 23, 2007 1:21 am
by goredsox
It could lend credence to the expanding universe theory, "Everything expands exponentially."
Supposedly space is expanding, not matter.
But if the space within matter
subatomically is expanding, both the space between celestial objects and the celestial objects
themselves would be expanding, without having to invoke the creation of matter, pair production, etc.
So all the mathematics in physics and astronomy that give us constants in terms of distance would have to be re-done from scratch, given the different reality of, say, 300 million years ago, when the continents were together. In fact, it would have to be redone for every point in time going backward and forward.
Kind of a tall order, eh?
Edit: No wait a minute, that makes no sense. If that were true, the crust would have expanded instead of cracking.
Posted: Sun Sep 23, 2007 3:54 am
by BMAONE23
I don't know if the mathematics of measurements would need to be alteres nor the method of measuring. If ALL is expanding, then even the devices used to make measurements would be expanding. If a Foot grew to be 13 inches, the ruler that measured it would also grow to be 13 inches in a foot but would still read as 12.
a light year would still be a light year long though the distance could double because the photon plank length would double and so the measurements would remain the same
Posted: Sun Sep 23, 2007 4:07 am
by BMAONE23
I just ran the Pangea Ultima animation and I gotta say, what happens to asia? It combines north & south america with africa, antarctica, and australia, but asia just disappears from view around the back of the globe.
Posted: Sun Sep 23, 2007 5:14 am
by goredsox
http://www.nealadams.com/nmu.html
Look at clips #0, #11, and #12 on the link.
Neal Adams proposed that the east coast of Africa fits up against the west coast of India. Then he has Australia and Antartica joining together and fitting against the eastern margins of Asia, which also has a major transformation as he folds Indonesian and all the surround Island nations into Southeast Asia and India. On the Northern frontier of Asia, he has Greenland, Northern Canada, and Alaska closing the Arctic Ocean gap for a nice fit (see clip #11 for that one). Africa and Europe stay where they are now, but he closes the gaps of the Mediteranian, Red, Black, and Caspain Seas like they are cracks in the pavement. His "Pangea" is one continent, covering the entire (smaller) globe with zero oceans.
Pretty remarkable work here. Only thing is, with computer animation, you can morph almost any selection of continents in any orientation together. In fact, he does tackle the surface features of the Moon, Mars, Europa, and Ganymede just in this way.
Posted: Sun Sep 23, 2007 6:13 am
by BMAONE23
Some of his moon work like clips 2,3 and 10 are interesting though.
Posted: Sun Sep 23, 2007 7:53 am
by adrianxw
I just read through some of that Neal Adams stuff. It would be difficult to debunk. Not because he is right, there is just so much wrong, it would be hard to know where to start!
Posted: Sun Sep 23, 2007 5:03 pm
by rigelan
You could start by asking just how much the earth is expanding per year in this theory. Assuming exponential growth, I calculated it out to an increase in circumference of 37 cm per year. In 10 years, it should have increased 3.7 meters. If this theory is true, then this increase in size should be noticable. (note how precisely we can measure it already
http://www.sciencedaily.com/releases/20 ... 110225.htm )
Yeah, I spent some time looking at Mr Adams' articles. If it weren't written in rant format, I might have a better time thinking about it. But rants just turn my mind off, and I automatically pick up nothing useful.
Then you could figure out how much the orbit of the moon and earth would change based on the changing masses, and the period of rotation of the moon. And you could reference documents from 1000's of years ago explaining how long it took the moon to orbit. They had suprisingly precise measurements. Compare them to today. See if the orbits have changed. It should be somewhat significant.
How about the increase of the mass of the earth affecting the speed of the earths rotation, i.e day and night? Conservation of momentum. Day and night would be longer, affecting our predictions of the paths of mercury and venus 1000's of years ago. Have those changed too?
Posted: Sun Sep 23, 2007 7:41 pm
by auroradude
I know I'm fairly ignorant but I too have problems with this projection of the drift of the continental plates.
It seems that the theory of the moon's formation has a Mars -sized body crashing into the Earth and "gouging out" a moon-sized blob of material that indeed becomes our moon.
The "hole" left behind becomes the Pacific Ocean. Now the Earth is out of balance and the super-continent Pangea breaks up and begins to fill in that hole. That is why the Pacific is surrounded with subduction zones and the Atlantic is spreading apart.
I know this is rather simplified but sometimes the simple solutions are the best. It clearly doesn't make sense that these land masses should come togeather again and throw the system again out of balance.
Posted: Sun Sep 23, 2007 8:03 pm
by rigelan
Well, the moon is larger than all the oceans of the world volume by a factor of 17.
The moon's volume is 2.19 x 10^10 km^3
All the oceans in the world make up 1.3 x 10^9 km^3.
So if it did grab some of the pacific, the area of the pacific is definitely not the majority of the mass of the moon.