Talk:Pangaea

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[edit] Archive -- Start a new discussion

[edit] 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)

Both. Eras consist of Periods. The Mesozoic Era consists of three Periods:
  1. Triassic
  2. Jurassic
  3. Cretaceous

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)

[edit] 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:

Pangæa
—
~300 mya – ~180 mya
—
Rest In Peace

—

— Ŭalabio 20:42, 2005 Mar 13 (UTC)


Continental Drift by Ken Glasziou, physicist, Australia


[edit] 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)

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)

[edit] 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)

[edit] 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)

[edit] 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)

[edit] 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)

[edit] 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)

[edit] 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)

[edit] "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)

[edit] 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)

[edit] 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)

[edit] 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
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.

[edit] 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)

[edit] 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)

[edit] 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)

[edit] 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)