Talk:Pangaea
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to this page and add the quality rating to that template instead of this project banner. See WP:PIQA for details.Mesozoic or Jurassic?
The article for Laurasia says that it broke off of Pangæa in the late Mesozoic era, not the Jurassic. Which is correct?
-- 70.17.234.158 20:18, 22 Dec 2004 (UTC)
Pangæa broke into Laurasia and Gondwana in the Jurassic Period of the Mesozoic Era. For more information, see geological timescale.
--
Ŭalabio 06:44, 2004 Dec 23 (UTC)
when???
"Pangæa broke up about 200 million years ago (mya). When the continents first came together to form Pangæa 180 mya,"
- So it broke up, and then' formed? - Omegatron 06:23, Mar 13, 2005 (UTC)
- It came together about 300 million years ago and broke apart about 180 million years ago:
—
— Ŭalabio 20:42, 2005 Mar 13 (UTC)
Continental Drift
by Ken Glasziou, physicist, Australia
Pangea and plate tectonics
Intro to article says that Pangea "existed ... before the process of plate tectonics separated the component continents". But later in the article there is reference to previous supercontinents Rodinia and Pannotia, and the supercontinent article says that these may be part of a series of supercontinents which formed, broke up and re-formed in cycles lasting around 250m years. So presumably there were tectonic plates moving around before the formation of Pangea, as well as after it broke up. Was plate tectonics somehow dormant during the lifetime of Pangea ? Gandalf61 14:22, Jun 1, 2005 (UTC)
The plates were not dormant; they simply weren't separating the landmasses but instead bringing them together. "The process" referred to would be the one that broke up Pangaea; clearly that process could not occur before Pangaea broke up!
I'd like to see a map with the plates superimposed on the map of Pangaea.
- I would like the know how the tectonic plates came together in order to form Pangaea. Isn't it unlikely that plates would move towards one another? --IntricateBalance 19:11, 8 May 2007 (UTC)
- Not at all unusual - Africa is presently moving toward Europe; Arabia is moving toward Asia; Australia is moving toward the Pacific and parts of the SE edge of the Eurasian plate; India is moving toward Eurasia; Western California and the is moving toward Alaska; South America is moving toward the Nazca Plate; The Indian Ocean plate is moving toward SE Asia (Sundaland). Is that enough? Cheers Geologyguy 23:45, 8 May 2007 (UTC)
- You didn't explain how. What you wrote above could just as easily be explained with the Earth Expansion theory. The reason I'm curious is because somehow I don't see why magma convection flow is adequate to explain why enormous tectonic plates move, let alone into one another.
- It's a common misconception that the )horizontal) plate motions are somehow 'driven' by mantle convection. That's wrong. The motion of the ocean floor isn't driven by convection, it is convection! The new crust created at the ridge is hot, low density and buoyant, so sits higher. The old crust (well, lithosphere strictly) where it's subducting is cool and higher density, higher than the mantle beneath and so it sinks. How to initiate subduction is an unsolved problem, but once it's started. the sinking slab pulls the surface plate along. Hence why the fastest moving plates tend to be the ones with larger portions of their margins subducting. 131.111.228.219 (talk) 11:09, 8 February 2008 (UTC)
- I would like the know how the tectonic plates came together in order to form Pangaea. Isn't it unlikely that plates would move towards one another? --IntricateBalance 19:11, 8 May 2007 (UTC)
Also, I believe the E.E. theory has a better explanation as to why the oceanic crust is only 200-300 million years old. It could be because as the earth expanded molten magma pressured outward from inside the earth then gradually lined and cooled at either side of the opened mantle (along the oceanic ridges-where the tectonic plates meet). This explains why the sea floor ages as it distances itself away from oceanic ridges where tectonic plates meet and where the newly formed outer layer is formed.
Its impossible for the oceanic crust to be 200-300 million years old if Pangaea spit apart because the oceans crust would not be newly created but merely shifted. --IntricateBalance 03:44, 9 May 2007 (UTC)
- Please see Expanding earth theory where you will see that "Very few geologists or geophysicists today support the expanded Earth" as well as the arguments for and against. Cheers Geologyguy 22:09, 9 May 2007 (UTC)
Please realize that they have yet to supply good reasons why.--IntricateBalance 02:43, 10 May 2007 (UTC)
- Simply reading the article would have answered your question. A quote: The primary objection to Expanding Earth Theory centered around the lack of an accepted process by which the Earth's radius could increase. This issue, along with the discovery of evidence for the process of subduction, caused the scientific community to dismiss the theory of an expanding Earth. The evidence for continental matching even on the Pacific facing sides became irrelevant, as did the claims that a smaller sized and lower gravity Earth facilitated the growth of dinosaurs to their relatively enormous size. Just Another Fat Guy 19:12, 9 July 2007 (UTC)
Name
Why is there this article, and another one called "Pangea" that is the same thing?
- 'Pangea' is only a redirect page.--Jyril 20:19, 18 September 2005 (UTC)
animatino duration
Can i suggest that I work on the animation (if possible through flash. Im not sure yet), to make it so that the end reasult of the Pangaea (when all the continents are at the present position) lasts longer, maybe 2 seconds longer? so that it gives the viewers more time to comprehend the facts that its the end result. For me, just seeing that the plates got back to saquare one right like that didnt make a good impression paat 03:14, 10 January 2006 (UTC)
Reference?
Does anyone have any references for the assembly and break-up of 300 Ma and 180 Ma? I'd like to use it for History of Earth.– Knowledge Seeker দ 04:01, 9 April 2006 (UTC)
- If you have not seen this one [1] try it - it covers the complete multiple opening-closing cycles for the Atlantic and its predecessor. Hope this helps --Geologyguy 23:33, 13 May 2006 (UTC)
Original Greek– which is correct?
On May 15, 2006, Gilgamesh changed the Greek lettering from Πανγαία to Παγγαία. This in effect reverses the change made by Geologyguy on May 13, 2006. It's unclear to me why Gilgamesh says there should be two gammas and no nu. Which is correct? --Mathew5000 08:06, 15 May 2006 (UTC)
- I changed it because I thought it was a simple typo - the derivation is from πάν, "pan-", meaning "all", and it made no sense to me to use two gammas, as the transliteration would then be "paggaea". Wicktionary [2] perpetuates the double gamma for Pangaea but uses the nu in the etymology. --Geologyguy 15:13, 15 May 2006 (UTC)
- Well I'm not entirely clear what Wiktionary is trying to say. Did the word "Παγγαία" exist in the Greek language before 1915? Wegener was writing in German, correct? Perhaps today, in Modern Greek, the word for "Pangaea" is "Παγγαία", but that isn't relevant to the etymology of the English word. (Unless the Greek word existed prior to 1915.) Probably the etymology in this article (and in Wiktionary for that matter) should be similar to what is done in the German Wikipedia article, giving the prefix and root separately. --Mathew5000 01:44, 16 May 2006 (UTC)
- By poking around a bit on Wikipedia I found out that in Ancient Greek the word "Παγγαῖον" was used for a mountain range in northern Greece (now called the Pangaion hills in English). --Mathew5000 03:32, 16 May 2006 (UTC)
- Anyone who understands Greek, please translate the first few sentences of el:Παγγαία; it looks like that might explain why the nu got replaced by an extra gamma. --Mathew5000 04:00, 16 May 2006 (UTC)
- First of all, Greek gamma represents two different consonants. If it exists before kappa, khi, ksi or another gamma, it's pronounced as a velar nasal /ŋ/. Secondly, the modifier pan- means "all". When compounded with a word, the last letter becomes mu if the next consonant is pi, beta, phi, psi or another mu, and it becomes gamma if the next consonant is kappa, khi, ksi or another gamma. This is a grammatical sandhi affect, reflected only in pronunciation when the words are separate, and reflected in spelling too if it's compounded. And "gaea", of course, means "earth". So (παν "all") + (γαία "earth") = (παγγαία "all earth"). The in-word spelling combination "νγ" does not exist in traditional Greek. - Gilgamesh 06:58, 18 May 2006 (UTC)
- BTW, just to be clear: γ = g. γγ = ŋg. γκ = ŋk. γξ = ŋks. γχ = ŋkh. There is usually no spelling for "gg", though κγ can be used for that if needed. Traditionally forbidden ν+combinations: νβ (=μβ), νγ (=γγ), νκ (=γκ), νμ (=μμ), νξ (=γξ), νπ (=μπ), νφ (=μφ), νχ (=γχ), νψ (=μψ). Traditionally frowned upon (but crept in, especially during the Koine Greek period): νζ (~ζ), νλ (~λλ), νρ (~νδρ), νσ (~σ). - Gilgamesh 07:21, 18 May 2006 (UTC)
- Thanks very much. Was the word Παγγαία a real Greek word in use prior to 1915? Or did Wegener "invent" the word? If the latter, then the article should be changed since the derivation of the English word is not really from "Παγγαία" but from "παν" + "γαία". Does that make sense? --Mathew5000 09:24, 18 May 2006 (UTC)
- Well, yes, the word was coined, but as Greek has traditionally been a synthetic language, the process of synthesizing new compound words from word roots is relatively straightforward and easily done. So the question is not "is that a real word in Greek?", but "is that synthesized properly as per Greek grammar?", which in this case it certainly is. - Gilgamesh 06:10, 20 May 2006 (UTC)
- Cool. And interesting. Thanks Gilgamesh, for the detailed explanation.--Geologyguy 13:33, 18 May 2006 (UTC)
Stuff
How was terrain heights, climate, vegetation (if any), hydrography etc in Pangea? Or recent studies still don't know? 200.230.213.152 04:29, 1 November 2006 (UTC)
Paragraph needs editing to remove vandalism...
Can someone remove the "Jerry is gay" off the beginning of the paragraph "Geography". It does not come up in the edit. I could not remove it...
--220.235.152.124 09:01, 7 December 2006 (UTC)
That means it already got fixed. You just needed to refresh the page. Just Another Fat Guy 19:14, 9 July 2007 (UTC)
"Appearances in Media" section
Does this section serve any purpose? As it is now, it's a fairly useless collection of random bits of information. I think the advice to "Avoid trivia sections in articles" applies. So, unless anyone has strong objections, I'd like to remove it.– bcasterline • talk 02:00, 20 February 2007 (UTC)
- I agree with you. Cheers Geologyguy 02:12, 20 February 2007 (UTC)
How do we know?
- I'm probably going to catch some h***/look stupid for asking this, but how do we know Pangaea existed? WizardDuck 15:59, 20 February 2007 (UTC)
Good question, we don't. Basically we humans have it all wrong. Pangea did not split apart and literal float thousands of miles, it was land first. What do we get after land? Rain. And then? A large river. Like an oceanic stream, which creates tsunamis. Precipitation occured in the Northern borders of land. The teutonic plates THEN create the mountains due to pressure. Of water and heat. That gif isnt too accurate for a more precise description. Thats why noone really does know. --129.174.54.24 20:20, 17 September 2007 (UTC)
- I think you raise a great point - we could use a good section on "evidence". To summarize for you right now, however - the evidence is broad and diverse, ranging from glaciation in formerly connected locations (South Africa, SE South America, India, etc, indicating that they were probably once in close proximity (the evidence of glaciation itself is from things like striated pebbles and the kinds of deposits that usually only are related to glaciers). Also, fossils - identical animals on now-separated continents at the same time. One of the original plant fossils that supported the idea was Glossopteris, a plant that only spreads by "runners" (like strawberries). Also, there is the continuity of the rocks - both the strata themselves (for example, a particular kind of sandstone whose composition, thickness, grain size, etc. is almost identical in South America and in Africa - and whose surrounding rock types are the same or similar) and the tectonic structures. An example of the latter is the headlands of deformed Appalachian rocks in Newfoundland, which are virtually continuous with similar folds and faults in Ireland and Scotland, implying a previous connection. That's just a sampling - other evidence includes paleomagnetic data, which show that the position of the poles, with respect to the continents, demand that the continents were once essentially connected. You can also look at the sequence of environments of deposition of rocks to infer the history - for example, a mountain range, then eroded piles of sediment, then broad lakes (as the continents started to pull apart), then marginal marine environments as a narrow sea formed, then no sources of sediment from the other direction as the continents got further and further apart. Hope this helps. Cheers Geologyguy 16:57, 20 February 2007 (UTC)
- This evidence applies to other formation theories like the planetary expansion theory. Unambiguous evidence for the Pangaean theory should only be unique to it to set it apart from the other theories . Perhaps we could divide the evidence section into two parts, those that aren't unique to the Pangaean theory, and those that are. --IntricateBalance 03:58, 7 May 2007 (UTC)
- All what you wrote must be present in the article. Otherwise it reads as a fantasy. The article must be thoroughly quoted and made clear that all these statments are reconstructions. I am also very suspicious about the absense of any controversy. I don't believe there exists only a single opinion about things no man could have possibly seen by their eyes. `'mikka 18:07, 25 February 2007 (UTC)
- Such "controversy" as exists is mostly disagreements on minor points. The big picture is well established and well documented and there is no disagreement among earth scientists. You are right, this evidence should be in the article. I'll put it on my "to do" list. Cheers Geologyguy 19:11, 25 February 2007 (UTC)
- the controversy concerns major factors such as the criticism of subduction and the disproportionate amassing of continents onto one side of the earth. The pangaea theory doesn't fully account for Mountain formation whereupon continent collision wasn't present. --IntricateBalance 03:58, 7 May 2007 (UTC)
I think humans know Pangea existed by Satellite imagery (If you go to Google earth and look at the sea water between Africa and The Americas, you will see a large "Crack" in the ocean, which is a tectonic plate, if you concentrate, you will see that it seems to fit with Africa's Western coast. Aswell as measuring the space between land every year, which is thought to extend 2 Centimeters each year because of hot gases in the Earth CONSTANTLY moving the tectonic plates/the land above the Asthenosphere.
- The Pangaea hypotesis was formulated well before the existence of Satellite imagery. However, at that time maps of the continents were already very precise. --Gspinoza 15:46, 18 March 2007 (UTC)
What about Balance?
- Essentially, the earth (or earth-moon system) must spin around a single center of gravity. And, the oceans must essentially cover a point equidistant from the center of gravity. The tides should be thought of as the effects of the moon's shift of the center of gravity of the earth-moon system rather than the effects of the moon's gravity on the water itself.
- There would essentially be only a few theories that could account for a "Pangaea" continent.
- 1 - Very asymmetric density distribution of subsurface matter (need a theory to substantiate).
- 2 - A second supercontinent that would offset the mass of the first one (where did it go).
- 3 - A satellite, moon, or twin planet locked in a synchronous orbit to offset the mass (would need a better explanation of where it is now, and how its departure (or collision) was associated with the equilibrium in plate movements).
- 4 - Some kind of a pimple effect.. of insufficient mass to cause the shift (hardly and explanation of a supercontinent).
- 5 - Growth of water and oceans (from what source?) at the same time as the breakup of the supercontinent, as well as necessarily having a second supercontinent as described above.
- http://michaelnetzer.com/rEvolution/content/view/92/83/
- Finally, how are you accounting to the changes in elevations of the continents tapering (with significant exceptions) from being higher in the middle to being lower at the coastlines. I.E. if Florida was in the middle of Pangaea, what was its elevation with respect to the West Coast of America? Where did the Mississippi river drain?--Keelec (talk) 01:27, 15 March 2009 (UTC)
- (See answer below at "Gah!": short version = no mass excess from continents)
Non-labeled green "gaps" in main image
In the top image on the page, there are a number of green sections of land that are not labeled. As someone who is not well-versed in the history of geology, I was curious as to what happened to these minor land masses. Did they go underwater, or did they combine with the larger bodies and fuse to the continents. Perhaps a small explanation should be given in the box along with the simple caption? Davemcarlson 20:09, 2 March 2007 (UTC)
- I moved your new message to the bottom, where most people will look for it... Most of the lines on the (admittedly crude) map in the article reflect modern coastlines so that people can have some referrent. In the upper part, one can discern Greenland, the Scandinavian Peninsula, a block that is land and adjacent continental seas of the British Isles, and so on. So they don't generally indicate discrete plates (although Greenland later pulled apart - a bit - from North America), but modern coastlines intended to give points of reference. Hope this helps. Cheers Geologyguy 20:22, 2 March 2007 (UTC)
Urantia
(long "essay" removed)
- I deleted the link; there is nothing in the Wikipedia article that refers to Pangaea, and even if it did, a book by a "mysterious author" can't be a reliable source. Cheers Geologyguy 21:19, 16 May 2007 (UTC)
I replaced the link, you had no right to delete the link. The Urantia book is a valid reference to the theory of plate tectonics and continental drift and an approved resource in this publication. Majeston cheers
The Urantia pseudoscience fiction has no place in this article and further attempts to add or promote it will be deleted. Vsmith 16:15, 24 May 2007 (UTC)
Vsmith. This is a discussion page regarding material about Pangaea. Your POV is respected but out of place. The material will remain if you wish to discuss it that is your privilege but you have no right to remove valid discussion material.
The further development of the theory of continental drift is reviewed by I. W. D. Dalziel in Scientific American 272 (1) 28 (1995). The date proposed for the commencement of break-up of the first supercontinent is now estimated as 750 million years ago—the same as is given in The Urantia Book. REFERENCES: The Urantia Book, p. 663; Scientific American 250 (2), 41, 1984; Scientific American 256 (4), 84, 1887; H.E. Le Grand, Drifting Continents and Shifting Theories, 1988. (Cambridge University Press)
— Preceding unsigned comment added by Majeston (talk • contribs) 19:06, 24 May 2007 (UTC)
- Rodinia is not Pangaea and urantia is not science - end of story. Vsmith 01:12, 25 May 2007 (UTC)
VSmith. Whether you personally believe it is science or not science is not the point. The threshold for inclusion in Wikipedia is verifiability, it is not whether you personally like or dislike the source of the information. The Urantia book has been in continuous print since 1955 and has quite a lengthy attribution in this publication as well as quite a few readers worldwide.
Timeline
Is it possible to render the 'Formation...' section as a timeline? The current article either assumes the reader is familiar with the various ages, eras, periods, or requires 'flipping back and forth' between Wikipedia pages to add context.Cander0000 19:43, 4 July 2007 (UTC)
Pangaea or pangea?
Which is it? When I was in high school we all said "Pangea" (like pan-gee-a), now my professors are saying pangaea (pan-gay-a)... Is this a regional difference or did they change it? I'm also curious which is technically correct because there are a couple of pages (like Plate tectonics) where it is sometimes referred to as one and sometimes as the other. This must be confusing for other people too! : ) L'Aquatique talktome 21:07, 15 October 2007 (UTC)
- Both spellings are equally correct. Pangaea is more British/European usage, Pangea is American. Wikipedia does not change British or American usage unless the article treats something that is distinctly British or American (or Canadian, or Australian, or any other variant of English). All other things being equal, it goes by the way it was used when the article was first created; it should be consistent within an article, though. As for pronunciation, there's no accounting for that. Cheers Geologyguy 21:23, 15 October 2007 (UTC)
- In Greek derivatives like this, "ae" and "e" are often alternate reflections of the Greek αι. Compare aeon/eon, aesthetic/esthetic, haematology/hematology (though never gaeology for some reason). As Geologyguy points out, the "ae" form is more common in British usage. It also happens with oe/e. Tarchon 01:55, 10 November 2007 (UTC)
- "Geology" etc are never spelt with "ae" because they're derived from gê rather than gaia (variant forms for "earth" in Ancient Greek). As for pronunciation, the usual rules for scientific words of Greek derivation would yield "pan-jee-a". The reconstructed Ancient Greek pronunciation would be "pang-guy-a" or thereabouts, and I'm guessing the modern Greek would be close to "pan-yeh-a". Your professors' version sounds kinda like how I'd render it in Swedish, but I imagine that isn't their source! Orcoteuthis (talk) 19:52, 12 January 2008 (UTC)
- Hi, there are two issues, orthography and pronunciation. First orthography: Indeed the word comes from Greek Παγγαῖα, which is transliterated in Latin as Pangæa, then Pangaea. This is the British spelling. American spelling has changed all ae to e, hence it uses Pangea. Now pronunciation: The Ancient Greeks would pronounce the word [paŋ'gaia], while the Modern Greeks pronounce it [paɲ'ɟea]. However, almost none of the Greek words are pronounced as such in English, so it's safe to use either versions you've heard. Because if you're indeed looking for the correct Greek pronunciation, then first listen to this: I'm a Greek living in the UK and when I'm trying to pronounce Greek words as they are actually pronounced nobody understands them! :-) -- Avg 21:04, 12 January 2008 (UTC)
"Geo-" and "Gaea" are certainly related through their roots. "Gaea" is the earth-god of (ancient) Greece, and her name is pronounced GEE-uh, much as "Geo-" (earth) is pronounced GEE-oh. —Preceding unsigned comment added by Websterwebfoot (talk • contribs) 18:16, 30 December 2008 (UTC)
proof of existence?
The bible mentions nothing of pangea, and also, the earth is only 4000 years old according to god —Preceding unsigned comment added by 71.201.151.133 (talk) 04:04, 12 March 2008 (UTC)
- Indeed, according to James Ussher the Earth was made in 4004 BC (at nightfall preceding Sunday October 23), so the Earth is only 6012 years old! Surely medieval clerymen and people living before the classical age know these things better than modern-age scientists! No sorry, I think they don't. 80.127.58.65 (talk) 14:07, 30 March 2008 (UTC)
- Actually it's supposed to be 6000 years, and furthermore the Bible does not really make claims about the age of the Earth, that's someone's interpretation. mike4ty4 (talk) 00:13, 19 June 2008 (UTC)
First I want to distance my comments as much as possible from that man who has a differing opinion from mine. Now on to the purpose of this post, I am of the opinion that Pangaea is a joke. The "evidence" in this article is a joke. Yes, surface features/animals are similar in different places, those are the reasons this theory was conceived in the 1920's, but does not validate it. Honestly, this is a very childish overly simplistic theory. Furthermore, we have been able to monitor the movement of the earth's surface for some time now and what we've seen DOES NOT support the Pangaea theory. Pangaea fanboys explain this away by saying it takes 250 million years to go through one continental cycle, something so slow we "will not be able to see significant changes in our lifetimes", how very convenient and suspicious. Actually the earth is big enough that if it was moving in this cycle we would have seen that already.
I have no idea how or why our Earth's surface appears as it does, but this THEORY on the topic is not a fact. We should be careful about mixing beliefs with facts, this is a belief/theory not a fact. I don't understand why Wiki writes about theories like this as if they are facts. Wikipedia devalues their content by misrepresenting theory as fact, this article exemplifies this flaw. Somebody should really change this article to read more like a theory. It's a good theory worth considering, and it might be right (though I would be shocked), but it's definatly NOT a fact at this point.
Clearly this is the mainstream view on how the surface was formed, probably because this is taught as a fact in school, but I do think this article should reflect that this theory is widely accepted as fact. I just think Wikipedia should be more honest about their information, for mankinds sake.
Theories are not facts, and theories accepted/promoted as facts are deleterious.
--24.21.72.6 (talk) 08:29, 9 July 2008 (UTC)
- The only reason you would have for arguing it (given that there's no credible alternative) would be the conflict with religion. Non-issue. 78.151.182.44 (talk) 05:56, 25 August 2008 (UTC)
^ Indeed. Also, saying that it is a theory just because there isn't a account in history talking about Pangaea is like saying that dinosaurs are a theory.
Read the evidence section. There IS enough of it to consider Pangaea as a continent that actually existed. Unless you think dinosaurs should be considered just a theory, too. —Preceding unsigned comment added by 190.139.38.67 (talk) 01:06, 10 November 2008 (UTC)
People used to believe the earth was flat... it took the 'religious' crowd to prove that wrong... Also, for Pangaea to work you would have to shrink Africa about 30% —Preceding unsigned comment added by 148.78.197.254 (talk) 20:29, 12 October 2008 (UTC)
No, they didn't believe that. It's a big misconception [3]. And there's enough evidence supporting the existence of Pangaea to leave the article the way it is. The only reason to argue it is if you believe in religion over scientific explanation.
What he said. Also, there is no need to shrink Africa for Pangaea to work.
comments
i don't bleave in the contal drift at all —Preceding unsigned comment added by 72.205.223.148 (talk) 23:05, 9 April 2008 (UTC)
- It's ok the contal drift doesn't bleave in you either -- Avg 23:13, 9 April 2008 (UTC)
Pangaea II
Should be a section or an article about the future Pangaea. JAF1970 (talk) 19:03, 15 July 2008 (UTC)
Was Pangaea Real?
Was Pangaea really real? Tell me the truth. Did Pangaea and Panthalassa really exist, or is that a made-up story?--98.199.76.184 (talk) 05:58, 28 July 2008 (UTC)
- The evidence points to yes - while there's no way to know for certain due to it being long before our time, there's enough backing for it to make it more than a made-up story. 78.151.220.24 (talk) 20:14, 16 October 2008 (UTC)
Pangaea in Alfred Wegener's view
Alfred Wegener was not such a famous scientist through-out the years of which he lived. He was doutbed and died thinking that he was a failour. But though many scientist discovered through-out the years that he was in fact correct, they made him feel like he fail and that all the research that he did was for nothing. He was in fact the one who helped us learn about where our country once was between and where it is now. He should have some recognition for what he did and there should be a day to honor all scientists who were and are helping us learn more about the world itself.
but he did fail! pangea is still in doubt —Preceding unsigned comment added by 74.143.59.210 (talk) 15:43, 23 September 2008 (UTC)
Alfred Wegener's view
Alfred Wegener was not such a famous scientist through-out the years of which he lived. He was doubted and died thinking that he was a failour. But though many scientist discovered through-out the years that he was in fact correct, they made him feel like he fail and that all the research that he did was for nothing. He was in fact the one who helped us learn about where our country once was between and where it is now. He should have some recognition for what he did and there should be a day to honor all scientists who were and are helping us learn more about the world itself.
Alfred Wegener was born in 1880, he died in 1930. Here is a passage which we think he said: "Scientists still do not appear to understand sufficiently that all earth sciences must contribut evedence toward unveiling the state of our planet in earlier times, and that the truth of the matter can only reached by combining all this evedince... It is only by combing the information furnished by all the earth sciences that we can hope to deturmine 'truth' here, that is to say, to find the picture that sets out all the known facts in the best arrangement and that therefore has the highest degree of probability. Further, we have to be prepared always for the possibility that each new discovery, no matter what science furnishes it, may modify the conclusions we draw." Alfred Wegener. The Orgins of Continents and Oceans (4th edition)
What are the theories about Supercontinents?
Are there any widely considered theories in the Scientific community about why supercontinents form, break apart and reform?
If so this would make an interesting section to the article.
66.227.84.101 (talk) 01:28, 19 December 2008 (UTC)
Correct a misspelling of Mississippian and emphasize that the concept of Pangaea is THEORY
First, on the chart "Appalachian orogeny" the word "Mississippean" is misspelled. Can we get that corrected very soon?
Second, we need to emphasize from the beginning of this article that this is a THEORY, not fact. All models of the evolution of earth are theories.
I disagree with the theory, but that does not mean we cannot present it as a theory.
FURTHER, to answer people's question about how tectonic plates can move, we might include something about how fragile the crust of earth actually is; more fragile than a hen's egg.
The earth is 7,000 miles across and the crust averages about 18 miles thick.
When compared to the shell of a chicken's egg in relation to its girth, earth's crust is four times thinner. The USGS website contains a chart that shows the earth's crust in section. We may want to include or reference that. Cheers! Websterwebfoot (talk) 18:41, 30 December 2008 (UTC)
- Of course it's a theory. However, it has every bit of support from seafloor spreading to correlated rock sections across continents to seismic tomography. I think that everyone knows that past continents are an extrapolation, so it's OK to leave that part out. I have no idea what you're trying to get at with the crust being thin, especially with respect to Pangaea - continental crust is about 40 km, oceanic about 10, but the mechanically rigid lithosphere which participates in plate tectonics is on the order of 10's to a few hundred km thick. Awickert (talk) 21:38, 19 January 2009 (UTC)
Gah!
I've been trying to understand the Formation of Pangaea section here, and it is very tough sledding. It seems like a bunch of often ungrammatical and sometimes contradictory sentences in no sort of logical order. If nobody else feels like working on this, I am inclined to toss the whole thing and start over from scratch -- I don't think I can make enough sense of the existing prose to repair it. Any reactions? Looie496 (talk) 04:38, 18 March 2009 (UTC)
- It looks like all the supercontinent names are tossed around in a bullet-point-like fashion without any reference as to where it's starting or heading, or any way for someone unfamiliar with them to get their bearings. I'd be willing to help you fix this, but I don't have the time right now, so I'd be more support-role. I think that maybe some integration / re-routing to a revamped supercontinent article could help, as could lots of maps and figures describing what came together to form it, especially ones of Earth in geologic time. Those are used in the geological time-period ones, such as Silurian. Also helpful would be correlations between current continents and the named proto-continents (i.e., Laurentia = North American cratonic core (much of US and Canada, not much of Mexico), etc. Awickert (talk) 06:58, 18 March 2009 (UTC)
- There might be benefits of combining all of the "Supercontinent articles" into a single article. Pangea, Vaalbara, Rodinia, Pannotia, and Supercontinent_cycle, as they seem to cover much the same ideas over different time periods.
- However, as I mentioned earlier, this supercontinent thing just doesn't make any sense. While people like the idea of reducing everything down to ONE... it just doesn't seem appropriate in this context. It is impossible to concentrate all of the mass of the crust on one side of the earth. Rock is denser than water (except for pumice). The oceans have to essentially cover the planet equidistant from the center of mass... So, any theory of a single supercontinent would also have to describe how a really bizarre mass distribution (eg. all the iron on the other side of the earth?) would allow it to happen. Or, you would have massive flooding, and more continents appearing and disappearing on the other side of the planet.
- How much evidence do we have that these supercontinents were formed all at the same time, rather than having the continents bumping into each other at different times?--Keelec (talk) 07:47, 3 April 2009 (UTC)
- It might be helpful to put them all together, but I think that there's too much info for one article, though an overview article could use beefing up. The first thing I want to do (thanks for getting my attention back to this, but I'm about to be leaving so it won't happen soon) is re-organize this so it's more about Pangaea than the whole history of the continents.
- To answer your question very quickly (since it's not related to editing the article), there is a ton of evidence that all of the continents were put on one side of the Earth at certain points in the geologic past, and for "Wilson cycles" of supercontinent formation and breakup. However, this doesn't do much to the overall mass distribution because the oceans and the continents are isostatically compensated: if you look at a map of the geoid, you'll see it doesn't correlate with topography. If you have other questions, I'd be happy to take a little time to answer on my talk page. Awickert (talk) 08:26, 3 April 2009 (UTC)
This article describes the point at which England became separated from North America - obvious satire apart, how did it subsequently become glued onto Scotland and Wales? I think we should be told.