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Divinus Arma
10-25-2006, 05:45
The concept of pangea as a precursor to the modern continental landmasses is a "fact" as taught in the United States public school system. While this is not a religious debate, religious interpretation is welcome. However, please do not turn this into a debate on the accuracy of carbon dating in respect to religion as that certainly deserves its own thread. I would like to discuss the concept of Pangea, and more importantly, the formulation of landmasses prior to pangea. The questions that initially attract me are: (1) If Pangea is an accurate theory for pre-continental earth, were oceans and topography nescessarily equivalent to allow for this single land mass? In other words, would it not be possible that much of Pangea would be underwater while other landmasses, which now lie underwater, were above sea level? I would assume this to be the case considering irrregular cycles in global warming and cooling which naturally take place thus causing various ocenaic water levels due to massive formations of ice at the poles. (2) What, if any, evidence does the concept of pangea contribute towards a divine existential perspective?

I would imagine a pre-pangea with ancient continents far different from our own. Billions of years past, a world unthinkable and unprovable due to a total errosion of any scientific evidence.

Papewaio
10-25-2006, 06:40
Sea crusts are significantly thinner then continental plates/cratons.

Also the age of most of the sea crust is significantly younger too.

Parts of the continental plates would have been underwater at one stage or another... thus seashells in mountains.

A quick look at the current landmasses and pangea shows that a large percentage of what is now was around then... there were different stages with more and less sea... but in the end the shape of the continents has changed that much considering the time period and the massive forces at work... it is amazing that they are still recognisable pieces of a puzzle.

Papewaio
10-25-2006, 06:46
I would imagine a pre-pangea with ancient continents far different from our own. Billions of years past, a world unthinkable and unprovable due to a total errosion of any scientific evidence.

Parts of the Western Australian Craton (craton is the central/core/stable bits of a continental crust) are aged at over 4 Ga... 4 Giga years... 4 Billion years old. While other parts are 3.6-2.7 Ga.

Age of the earth is 4.6 Ga years.

Sasaki Kojiro
10-25-2006, 08:01
The concept of pangea as a precursor to the modern continental landmasses is a "fact" as taught in the United States public school system. While this is not a religious debate, religious interpretation is welcome. However, please do not turn this into a debate on the accuracy of carbon dating in respect to religion as that certainly deserves its own thread. I would like to discuss the concept of Pangea, and more importantly, the formulation of landmasses prior to pangea. The questions that initially attract me are: (1) If Pangea is an accurate theory for pre-continental earth, were oceans and topography nescessarily equivalent to allow for this single land mass? In other words, would it not be possible that much of Pangea would be underwater while other landmasses, which now lie underwater, were above sea level? I would assume this to be the case considering irrregular cycles in global warming and cooling which naturally take place thus causing various ocenaic water levels due to massive formations of ice at the poles. (2) What, if any, evidence does the concept of pangea contribute towards a divine existential perspective?

I would imagine a pre-pangea with ancient continents far different from our own. Billions of years past, a world unthinkable and unprovable due to a total errosion of any scientific evidence.

There have been several other supercontinents before pangea...can't remember there names. Some kinds of rocks contain paleo-compasses if you will, they are a record of where the poles were in relation to that rock in the past. Geologists have a good idea of the paths the continents have taken.

We have new sea crust created (e.g. mid atlantic ridge) and destroyed when it is subducted and melts. Sea crust isn't that old. The land crust sticks around though, and stays above water...remember the mantle is solid, for former land to be underwater now we would have to have a lot more water than in the past.

(2) none

macsen rufus
10-25-2006, 12:34
[Holds breath]Waiting for Navaros.... [/]

lancelot
10-25-2006, 14:53
Parts of the Western Australian Craton (craton is the central/core/stable bits of a continental crust) are aged at over 4 Ga... 4 Giga years... 4 Billion years old. While other parts are 3.6-2.7 Ga.

Age of the earth is 4.6 Ga years.

Interesting info...Kinda makes human existence seem a bit insignificant when looked at like that...

Kanamori
10-25-2006, 16:38
In other words, would it not be possible that much of Pangea would be underwater while other landmasses, which now lie underwater, were above sea level?

...It doesn't seem likely. The two masses would somehow have to change relative heights. What could cause long term bulges in the crust like that? It is more reasonable to say that the masses above water simply have more volume than it would be to say that they rose and fell due to some internal-outwards planetary force. That doesn't mean it's impossible, but there are tons of other possibilities that cannot be ruled out. There is evidence for plate movement. There are layered groupings of rock, strata, that match both in the composition of layers and in radioactive dating, which suggests that tectonic motion we have observed, like the transform motion at the San Andreas fault, is responsible for those changes in global position.


What, if any, evidence does the concept of pangea contribute towards a divine existential perspective?

It adds no divinity, in my mind. Maybe in the mind of a geologist having an acid trip... :pinchmynoseitsqueaks: err... I mean :clown:

Philippus Flavius Homovallumus
10-25-2006, 19:22
http://www.news.utoronto.ca/bin1/001206a.asp

This is interesting, suggesting that the landmass was formed quite quickly.

Pangea was the last super continent and is well beyond human memorey, so you can't use it to justify any mythological understanding of the world.

rory_20_uk
10-25-2006, 19:22
We start with facts
With facts we then extrapolate backwards to form theories.

Yes, the earth might be 300 years old, and that God is taking the piss. Perhaps Aliens created everything (perhaps they're God).

And so perhaps thin basalt oceanic rock suddenly became thick quartz laden continental rock and jumped up.

The best evidence we have shows that at place boundries the dense oceanic crust goes underneath the lighter continental crust.

Of course, there is probably a point in the past where as you say there is noevidence one way or another. But the probability is that the world still followed the same rules that is does now.

I'd suggest the book "Strata" by Terry Pratchett for more evidence on the alien theory. Or failing that a decent book on Geology would be a good way of looking into the accepted theory.

~:smoking: