Talk:Subduction/Archive 1

Archive 1

Orogeny

Subduction can lead to orogeny. -FZ 16:52, 3 Aug 2004 (UTC)

--- My recent tweaks were purely for flow, emphasis and clarity. Please correct any errors I might have inadvertently introduced. --Wetman 23:08, 22 May 2005 (UTC) --

images...

The top image of subduction zone is simply wrong. Too many mistakes, I remove it. Geojide 16:44, 18 September 2006 (UTC)

It does show a rough estimate of the correct rate of decent though.

would you elaborate on what those mistakes are? thanks. Lunch 18:52, 2 November 2006 (UTC)

The diagram used to illustrate subduction near the top of the article is factually incorrect. Melt produced during subduction is not derived from directly melting of the subducting slab. It is however derived from water released during dehydration of the slab during subduction, this water rises upwards into the overlying Mantle wedge and causes melting to occur there. The diagram on this article has melt forming from the slab and entering the crust or possibly lithosphere, a common mistake but one which one fail you first year geology. Here's is a link to a correct illustration http://www.calstatela.edu/faculty/acolvil/plates/subduction.jpg

However I'm not familiar with the procedures of using other peoples work on wikipedia so I'll research a little before doing anything (Climberdave 12/03/07)

The image cited is almost certainly copyrighted (and probably not by the university owner of that page) and cannot be used. If you can get it explicitly (in writing) released to the public domain, or for any use (non-commercial only is not enough), that would be great. Geologyguy 16:47, 12 March 2007 (UTC)

Would it be possible for me to create a suitable alternative diagram? (Climberdave 14/03/2006 12:00GMT)

Certainly - anything you create, you own the copyright to and can do what you want with. Just be sure you don't "copy" a copyrighted image - i.e., using the one cited above as a "go-by" would be a no-no. Cheers and thanks - Geologyguy 13:28, 14 March 2007 (UTC)

Tricky one, but I'll give it ago when I get a chance, CLimberdave

Its going to be about a month now before I get a chance to produce a new graphic, in the mean time i'll try looking for a suitable one or asking one of my professors to provided one for us ClimberDave

Disposal of nuclear waste

It might be good to include a discussion on the merits or otherwise of disposing nuclear waste at subduction zones.

It's not a good idea unless you like radioactive volcanoes. ~~ —Preceding unsigned comment added by Earthophile (talk • contribs) 02:22, 11 July 2010 (UTC)

By the time any waste melted down and percolated up to the volcanoes, most of the radioactive isotopes would have long since decayed. I'd be more concerned with whatever containers the waste was in rupturing during the actual subduction process.107.208.176.241 (talk)

Subduction Initiation

Article needs addition/touching up of current hypothesis regarding subduction initiation, willing to give it ago when I get some free time, however it is an important topic and could do with someone to read over and edit once its done ClimberDave 17:42, 21 April 2007 (UTC)

I don't mind helping out with this. MeanStreets "...Chorizo..." 10:44, 24 April 2007 (UTC)

I'll give it a go at the end of this week, hopefully have a suitable first draft shortly after that ClimberDave 19:10, 28 April 2007 (UTC)

In the general description section it is mentioned that subduction occurs because of mantle convection but the section on origin of subduction mention that there are different theories for the origin of subduction. Also from the video lectures, How Earth Works, of Professor Michael E. Wysession, in which he clearly mention that we can not say whether mantle convection started subduction or its the other way around, I guess, it would be better to remove or modify the last paragraph of general description section. I need few views before modifying it. Alok Bansal (talk) 11:38, 28 June 2012 (UTC)

Vandalism

Oh man, I laughed at this. It's all of the general description, you can't miss it. —Preceding unsigned comment added by 213.202.174.226 (talk) 01:40, 7 November 2008 (UTC)

Thanks for pointing it out, but putting it right would have been more useful than just laughing at it. Mikenorton (talk) 10:04, 7 November 2008 (UTC)

Accuracy about direction of arc?

This article states "Subduction zones are arc-shaped, with the concave side oriented away from the direction of subduction because of the curvature of the Earth." This seems to me to indicate that that the concave side of the arc would occur on the subducting plate side, not the over riding plate side. This doesn't seem to be correct. Consider the Aleutian Islands where the Pacific plate is sliding under the North American Plate and the arc is on the northern (over riding plate side). In South America, the seven arcs are either straight (not concave) or are concave on the continental side. At the very least, this needs to be reworded for clarity.

An additional thought: If the curve of arcs is related to the curvature of the Earth then one would expect all arcs to have similar radius, subject only to variations in the subduction angle. This doesn't seem true in Andes subduction zone. Is it true at all?

The article states: "The absence of volcanism in the Norte Chico region of Chile is believed to be a result of a flat-slab subduction caused by the Juan Fernández Rise." There needs to be an explanation of flat-slab subduction and why it doesn't cause volcanism. This may also relate to why subduction of continental crust in continental-continental convergence doesn't cause volcanism. (Lack of water?)

Come to think of it, it might be good to have a discussion of the difference in the net effects of the three main types of convergence: oceanic-continental, oceanic-oceanic and continental-continental. How do they differ, how are they similar.RStillwater (talk) 17:36, 20 November 2008 (UTC)

96.252.103.113 (talk) 14:31, 20 November 2008 (UTC)

Removed the paragraph as erroneous over-generalization. Vsmith (talk) 14:57, 20 November 2008 (UTC)

I beg to differ re: the arc issue. In fact, all oceanic plate subduction zones are fundamentally arc-shaped due to the curvature of the earth. The variations from this occur where the overriding plate is continental and its irregular mass is superimposed on the earths curvature. And yes, the arc is concave FACING the direction of subduction. Cut an orange peel at a subduction-angle and see for yourself. Tmangray (talk) 20:08, 23 April 2010 (UTC)

I might add, one would be hard-pressed to find ANY line on a globe that isn't an arc. Tmangray (talk) 03:09, 24 April 2010 (UTC)

For various reasons I have only just caught up with this page but my attention was drawn of it by one of my post graduate students. The formation of the arc in relation to subduction is more correctly due to the act of subduction. The crest of the arc ALWAYS points at the plate which is being subducted due to processes that are similar to those that occur in rivers and glaciers. The fastest motion is always in the centre due to the reduced friction. So it is with arcs. The trailing edges lead back to the overriding plate - see the Antilles arc, South Sandwich arc. Even if the arcs formed on a true horizontal surface they would still have a arc in plan hence their plan has nothing to do with the shape of the Earth stricto senso.The Geologist (talk) 16:00, 22 March 2015 (UTC)

Neal Adams

Old fringe POV pushing
The following discussion has been closed. Please do not modify it.
Neal Adams have presented a totally contradicting theory about the Earth, in which there is no subduction. Should his theory not be mentioned in this article? knutars (talk) 20:09, 24 January 2009 (UTC) No, because his wording of his theory at [1] is full of rhetoric and faulty information about geology on which he bases his claims. His statement about mountain building is incorrect, and he seems to not understand things as mundane as conservation of mass. I can expand if necessary, but would prefer to spend my time elsewhere. As a second matter, in Wikipedia convention, new comments appear at the bottom of a talk page, and should not be marked as "minor" edits. Thanks for the mention though - it was a funny (if scary) read about the failures of science education. Awickert (talk) 20:21, 24 January 2009 (UTC) Knutars is correct. Neutral point of view is a fundamental Wikimedia principle and a cornerstone of Wikipedia. All Wikipedia articles and other encyclopedic content must be written from a neutral point of view, representing fairly, and as far as possible without bias, all significant views that have been published by reliable sources. This is non-negotiable and expected of all articles, and of all article editors. For guidance on how to make an article conform to the neutral point of view, see the NPOV tutorial; for examples and explanations that illustrate key aspects of this policy, see Wikipedia:Neutral point of view/FAQ. Information suppression A common way of introducing bias is by one-sided selection of information. Information can be cited that supports one view while some important information that opposes it is omitted or even deleted. Such an article complies with Wikipedia:Verifiability but violates NPOV The fact that no NPOV or criticism is tolerated of the subduction hypothesis demonstrates a violation of NPOV and information supresssion.Sophergeo (talk) 13:31, 20 March 2009 (UTC) Feel free to mention Adams ideas and computer graphics in his article (already there). However, a cartoon artist's speculations have no place in a geology article and to refer to Adam's speculations as a theory is quite absurd. Carey developed the expanding earth hypothesis back in the 50s-60s during the time when abundant new evidence was being found and the theory of plate tectonics was developing. Although Carey's ideas were basically considered and rejected, they were notable. However, a cartoon artist's speculations about Carey's hypothesis simply aren't notable here. Vsmith (talk) 19:46, 20 March 2009 (UTC) Please address the factual issues I bring up before adding material back. Neutral point of view means that the point of view of the article best represents all angles of the facts. Wikipedia articles about science must necessarily stay factual, and may not include every popular hypothesis that exists. Awickert (talk) 04:38, 21 March 2009 (UTC) Also, the NPOV allegations are incorrect; see the fringe theory section of the NPOV page. Awickert (talk) 05:15, 21 March 2009 (UTC) "The ArbCom ruled that the following should generally not be characterized as pseudoscience: Questionable science: "Theories which have a substantial following, such as psychoanalysis, but which some critics allege to be pseudoscience, may contain information to that effect, but generally should not be so characterized."Sophergeo (talk) 05:19, 21 March 2009 (UTC) It (a) does not have a substantial following (at least, from my definition of substantial), and (b) I think is more than alleged to be pseudoscience: it is a collection of theories that is unsupported by the facts (seismic imaging, geochemical signatures, volcanism, etc.). I currently have it under "Obvious pseudoscience: 'Theories which, while purporting to be scientific, are obviously bogus...'", because (at least) Neal Adams' source includes fundamental misunderstandings about geologic concepts, and because I have yet to see a way this theory gets around conservation of mass, which is a fundamental physical principle. Awickert (talk) 05:47, 21 March 2009 (UTC) "The ArbCom ruled that the following should generally not be characterized as pseudoscience: Questionable science: "Theories which have a substantial following, such as psychoanalysis, but which some critics allege to be pseudoscience, may contain information to that effect, but generally should not be so characterized." Furthermore, your unverifiable and unsourced personal POV opinions and straw man fallacies do not justify the abandonment of the NPOV principle or the suppresion of verified and reliable information. Your claim that the universe violates the conservation of mass is unverifibale and unsourced. See below.Sophergeo (talk) 05:59, 21 March 2009 (UTC) Your re-addressing your previous statements without addressing what I say is (a) rude, and (b) unproductive. Please refrain from personal attacks; you have given no reason why my "straw man fallacies" are fallacies and the articles are true. To save on time, let's discuss here, instead of on Ganymede. I am doing my best to work with physical principles; if you would like to have a 2-way discussion of the merits of the theory, I would be happy to, and I believe that that would be more productive. For one reliable source, I use Geodynamics, a general geophysics textbook. Awickert (talk) 06:12, 21 March 2009 (UTC) As to conservation of mass, I didn't say anything about the Universe, just about the Earth, and I didn't say it that Earth violates the conservation of mass, but that I don't see how an expanding Earth theory wouldn't violate it. So tell me, how does the expanding Earth theory conserve the mass of Earth? Awickert (talk) 06:15, 21 March 2009 (UTC) I would like to know what Neal Adams' theory has to say about the "evidence of subduction" presented by mainstream science. Does it reckon it at all, and if so, how does it explain it ? Otherwise, how does it refute it ? Obviously, "evidence", whether or not it is truly evidence, has to be addressed by any theory of the field. Fredofromstart (talk) 16:04, 1 September 2009 (UTC)

NPOV: Criticism and Controversy

Collapsing long discussion on the scientific acceptance of subduction. The reliable sources were all from the 50's and the 60's, before tectonics was accepted. No recent reliable sources were given for scientists doubting subduction.
The following discussion has been closed. Please do not modify it.
Related RfC on the matter has been closed. --Enric Naval (talk) 09:33, 24 March 2009 (UTC)}} Neutral point of view is a fundamental Wikimedia principle and a cornerstone of Wikipedia. All Wikipedia articles and other encyclopedic content must be written from a neutral point of view, representing fairly, and as far as possible without bias, all significant views that have been published by reliable sources. This is non-negotiable and expected of all articles, and of all article editors. For guidance on how to make an article conform to the neutral point of view, see the NPOV tutorial; for examples and explanations that illustrate key aspects of this policy, see Wikipedia:Neutral point of view/FAQ. "Neutral point of view" is one of Wikipedia's three core content policies. Information suppression A common way of introducing bias is by one-sided selection of information. Information can be cited that supports one view while some important information that opposes it is omitted or even deleted. Such an article complies with Wikipedia:Verifiability but violates NPOV. I therefore propose to add the the following verified and reliable facts and sources: Intense criticism has been directed at the subduction hypothesis, particularly by proponents of alternative tectonic theories such as expansion and pulsation. Geologist S. Warren Carey famously said, "Subduction is a myth" and compared it to a religion. Geologist Yuri Chudinov wrote, "There is no doubt that the subduction model constitutes the weakest link in the construction of plate tectonics, as has been repeatedly pointed out," and he added, "Now that the subduction concept has been developed for almost 30 years, it can be said that it has not been fruitful geologically." In 2005, research seismologist Stavros T. Tassos of the National Observatory of Athens and geologist David Ford said subduction is "impossible" and compared it to trying to hammer a wooden nail into a cannonball, "More realistically, the appropriate and credible physical metaphor for subduction would be of a wooden nail being projected very slowly into a cannon ball. This is, of course, impossible, even over infinite time...." After the 2007 AAPG European Energy Conference in Athens Greece, research seismologist Tassos and geologist Karsten Storedtvedt of the University of Bergen in Norway wrote, "In the oral session, except for one presentation that was clearly pro plate tectonics, and another one that did not address the issue of global and large scale geology specifically, there was general consensus that subduction, and therefore plate tectonics, is mechanically impossible." Scalera, G., Are Subduction Zones, Actually Mantle Wedges Upduction?, Geophysical Research Abstracts, Volume 7, 07211, 2005 Scalera, G., The Geodynamic Meaning of the Great Sumatran Earthquake, New Concepts In Global Tectonics, 2005 Griffin, W.L., and O'Reilly, S.Y., Eclogites in the SLM: The Subduction Myth, IAVCEI, 6, 2006 Griffin, W.L., and O'Reilly, S.Y., Cratonic Lithospheric Mantle: Is Anything Subducted?, Episodes, Volume 7, Number 1, Pages 43-53, 2007 Sophergeo (talk) 05:17, 21 March 2009 (UTC) Your sources 3 and 4 do not debate whether subduction occurs. That leaves you with one scientist in your sources. Geophysical Research Abstracts is not seriously reviewed: it is more of a collection of hypotheses; the second publication is published in a newsletter by an organization that opposes the idea of plate tectonics. In this newsletter article, the driving stress for the earthquake is not given. Even with the negation of subduction, so long as one accepts a viscous, deforming, mantle, there is no reason to believe that it will suddenly push upwards on a piece of the rigid lithosphere. As a matter of fact, I would generally think that it would tend to deform laterally before it could put enough stress on the lithosphere. So there doesn't seem to be much support, and from the references, the theory is not well-developed except as an alternate explanation to a theory (plate tectonics) for which much evidence exists and geodynamical causality and boundary conditions are satisfied. Awickert (talk) 05:58, 21 March 2009 (UTC) I provided 10 sources so you ignored 60% of them. Your personal POV opinions do not justify the abandonment of NPOV or the suppression of verified and reliable information. This is an encyclopedia.Sophergeo (talk) 06:04, 21 March 2009 (UTC) I thought that was supposed to be a reference list at the end. I'm adding a reflist and going through the others. Please address my comments on the others instead of making accusations, especially when your sources seem doubtful so far, if not doubtfully relevant. I'm skeptical of what you say, but that doesn't mean that I'm not willing to work with you in some way; continued personal attacks and accusations will change that. Awickert (talk) 06:24, 21 March 2009 (UTC) I'm sorry if you interpreted my remarks as a personal attack. I am simply stating Wikipedia policies regarding NPOV and information suppression.Sophergeo (talk) 06:47, 21 March 2009 (UTC) Thanks for the apology; I just want the discussion to be a 2-way street about the concepts, evidence, and sources, instead of a unilateral "that's POV and wrong!". Awickert (talk) 07:04, 21 March 2009 (UTC) Carey's book is his book, and has his theories. It means he thinks a lot of them, but as it is not peer-reviewed, it doesn't say much about outside opinion. Opinions of non-notable geologists are unimportant per WP:WEIGHT. The Tassos article makes me see (maybe) the conservation of mass, but now I have to assume that atoms spontaneously(?) form in the core, which violates another fundamental physical principle about the creation and destruction of matter, and is published in Journal of Scientific Exploration, famous for fringe science. In any case, the analogy completely ignores the rheologies of the mantle and lithosphere (see the Geodynamics source above for info on the rheology), which shows that at least the quoted part of the article is inconsistent with our observations of Earth's interior. An AAPG conference is a conference; the reference to plate tectonics comes from a discussion on a self-published source (not allowed, see WP:SPS), which states that one scientist asserted his opinion. But the AAPG really isn't that interested in subduction, and there is no link to the actual abstracts referenced. Overall, the only thing I see of merit would be the book, and perhaps the paper, in representing a fringe theory that (as far as I've read) has no real scientific basis. Awickert (talk) 06:41, 21 March 2009 (UTC) Your personal POV and analysis are interesting but unverified and unsourced and do not justify the suppression of verified and reliable information regarding criticism of subduction. Carey's first book, The Expanding Earth (1976), was in fact peer-reviewed as it was published by Elsevier Scientific Publishing. The personal POV that the accumulation of matter on the Earth violates the conservation of mass is also unverified and unsourced and does not justify the suppression of verified and reliable information. Here are some more verified and reliable sources, all peer-reviewed, and in particular note Carey's peer-reviewed article published in Nature: Egyed, L., Some Remarks On Continental Drift, Pure and Applied Geophysics, Volume 45, Number 1, 1960 Cox, A., and Doell, R.R., Palæomagnetic Evidence Relevant to a Change in the Earth's Radius, Nature, Volume 189, Page 45, 1961 Carey, S.W., Palæomagnetic Evidence relevant to a Change in the Earth's Radius, Nature, Volume 190, Page 36, 1961 Dietz, R.S., Continent and Ocean Basin Evolution by Spreading of the Sea Floor, Nature, Volume 190, Pages 854-857, June 1961 Ward, M.A., On Detecting Changes In The Earth's Radius, Geophysical Journal International, Volume 8, Issue 2, Pages 217-225, May 1963 Creer, K.M., An Expanding Earth?, Nature, 205, Pages 539-544, Feb 1965 Meservey, R., Topological Inconsistency of Continental Drift on the Present-Sized Earth, Science, Volume 166, Number 3905, Pages 609-611, Oct 1969 Jeffreys, H., Imperfections of Elasticity and Continental Drift, Nature, 225, Pages 1007-1008, Mar 1970 Wilson, H.H., Late Cretaceous Nappes in Oman Mountains and Their Geologic Evolution; Discussion, AAPG Bulletin, Volume 57, Number 11, Pages 2282-2287, Nov 1973 Steiner, J., An Expanding Earth On The Basis of Sea-Floor Spreading and Subduction Rates, Geology, Volume 5, Number 5, Pages 313-318, 1977 Lambeck, K., The Earth's Variable Rotation: Geophysical Causes and Consequences, Page 449, 1980 Mundy, B., A Review of the Expanding Earth, Origins, Volume 12, Number 1, Pages 41-45, 1985 Grand, S.P., Tomographic Inversion for Shear Velocity Beneath the North American Plate, Journal of Geophysical Research, Volume 92, Number B13, Pages 14,065-14,090, 1987 Mundy, B., Expanding Earth?, Origins, Volume 15, Number 2, Pages 52-69, 1988 Noel, D., Continental Drift and Earth Expansion, Nuteeriat, Chapter 3, Pages 22-41, 1989 Tassos, S.T., Earth Expansion Versus Plate Tectonics or Approaching Reality Versus Mental Artifacts, New Concepts In Global Tectonics, Volume 4, Pages 13-17, 1997 Shields, O., Geodetic Proof of Earth Expansion?, New Concepts In Global Tectonics, Volume 4, Pages 17-18, 1997 Shields, O., Rapid Earth Expansion: An Eclectic View, Gondwana Research, Volume 1, Number 1, Oct 1997 Scalera, G., Paleogeographical Reconstructions Compatible With Earth Dilation, Annali di Geofisica, Volume 41, Number 5-6, Pages 819-825, 1998 Tassos, S.T., Excess Mass Stress (E.M.S.): The Driving Force Behind Geodynamic Phenomena, Proceedings of the International Symposium On New Concepts In Global Tectonics, Pages 26-34, Nov 1998 Pratt, D., Plate Tectonics: A Paradigm Under Threat, Journal of Scientific Exploration, Volume 14, Number 3, Pages 307-352, 2000 Maxlow, J., Quantification of an Archaean to Recent Earth Expansion Process Using Global Geological and Geodetic Data Sets, Curtin University of Technology, Department of Applied Geology, 2001 Scalera, G., The Global Paleogeographical Reconstruction of the Triassic and the Paleoposition of India, Annali di Geofisica, Volume 44, Number 1, Pages 13-32, 2001 Arp, H.C., Are Plate Tectonics The Wrong Answer To The Right Question?, Journal of Scientific Exploration, Volume 15, Number 1, Pages 134-138, 2001 Scalera, G., Relations Among Expanding Earth, TPW, and Polar Motion, Annali di Geofisica, Proceedings of the International Symposium on New Concepts in Global Tectonics, Pages 137-50, 2002 McCarthy, D.D., The Transpacific Zipper Effect: Disjunct Sister Taxa and Matching Geological Outlines That Link the Pacific Margins, Journal of Biogeography, Volume 30, Issue 10, Pages 1545-1561, 2003 Scalera, G., The Expanding Earth: a Sound Idea for the New Millennium, Why Expanding Earth? A book in Honour of Ott Hilgenberg, Pages 181-232, 2003 Briggs, J.C., The Ultimate Expanding Earth Hypothesis, Journal of Biogeography, Volume 31, Issue 5, Pages 855 - 857, Apr 2004 Lunde, G., A New Scenario For Earth Development, Journal of Petroleum Geology, Volume 27, Number 2, Apr 2004 McCarthy, D.D., Biogeographical and Geological Evidence for a Smaller, Completely-Enclosed Pacific Basin in the Late Cretaceous, Journal of Biogeography, Volume 32, Issue 12, Pages 2161 - 2177, 2005 McCarthy, D.D., Biogeography and Scientific Revolutions, The Systematist, Number 25, Pages 3-12, 2005 Herndon, J.M., Teaching Earth Dynamics: What's Wrong With Plate Tectonics Theory?, 2005 Herndon, J.M., Whole Earth Decompression Dynamics, 2005 Briggs, J.C., Another Expanding Earth Paper, Journal of Biogeography, Volume 33, Issue 9, Pages 1674 - 1676, 2006 Scalera, G., Are Artificial Satellite Orbits Influenced By An Expanding Earth?, Annals of Geophysics, Volume 49, Number 2/3, Apr/Jun 2006 Crawford, A.R., The Myth of a Vast Oceanic Tethys, the India-Asia Problem and Earth Expansion, Journal of Petroleum Geology, Volume 2, Issue 1, Pages 3-9, Dec 2007 Crawford, A.R., The Pangaean Paradox: Where Is It?, Journal of Petroleum Geology, Volume 5, Issue 2, Pages 149-160, Dec 2007Sophergeo (talk) 07:32, 21 March 2009 (UTC) (I'm letting the sources go down to the bottom for convenience.) Instead of blanket rejection of my analysis, I would appreciate some acknowledgment of some of the general issues with the sources you previously used, and the Wikipedia policy that goes along with them. As to your response: single-author books, even through scientific publishers, are generally not peer-reviewed to the extent that journal articles are, which is why articles are the gold standard: books are allowed more leniency on propositions of fringe ideas. Though not explicitly sourced, my analysis is verified and has support. I am citing the Wikipedia article on Journal of Scientific Exploration and its sources, and the article in the journal, for my comments on it. I am citing Geodynamics (the book) for mantle rheology. I am citing the fact that petroleum is largely in sedimentary basins and the general titles of the sessions at the meeting for the disinterest of the AAPG in subduction zones compared to sedimentary basins; I could find a real source, but it wouldn't really be worth it as I can tell you on my own authority that it's true. I would still appreciate if you could tell me where the extra mass required for an expanding Earth would come from, or why it would lose density; it would help the discussion. If you want a source, I am citing the continuity equation. I believe that that's all that I said that needs to be sourced, and that it was all at least implicitly sourced above, asking for sources on my comments is pretty nitpicky; I generally like to assume that comments on WP are factual. Throwing a bunch of sources at me isn't a way to keep a discussion going that will convince other editors that this is worth anything more than a fringe theory that has some support. It's fine if you want to ignore my POV, but my points still stand, and actively engaging in the debate is important. I've looked through your articles above; I see no reason to look through yours below yet because (a) it seems pointless until you acknowledge what I have to say about your articles, and confront my statements instead of telling me that I am wrong because I am writing what I think, and (b) based on my sample set above, a number of the bottom sources likely aren't relevant and/or aren't worth my time to look at. Sorry - but unless you make it worth my while to look at the sources (instead of "bah, POV"), it really doesn't matter whether I see them or not. Awickert (talk) 09:01, 21 March 2009 (UTC) (This isn't about "convenience." It's about NPOV and information suppression.) There is no Wikipedia policy that says verifiable and reliable sources must be peer-reviewed. As far as your claim that single book sources are not peer-reviewed, that is irrelevant as far as NPOV and information suppression are concerned. What is your reaction to the peer-reviewed sources posted above? Your POV does not justify information suppressionSophergeo (talk) 09:27, 21 March 2009 (UTC) I was just trying to keep the conversation together by putting the sources at the bottom. On controversies, there is Wikipedia policy that sources must be peer-reviewed and reliable. Peer-reviewed respected journals are the gold standard for science. I see no reason to respond to the sources above until you show interest in my earlier responses. Unless you can give me answers to my questions, the most I'm going to say is that this is a pile of work that is supported, but is ultimately physically impossible, and not based on my POV, but on conservation of mass and continuity. So for the last time: can you answer a direct question about the material you are proposing? How does it satisfy conservation of mass? Awickert (talk) 09:38, 21 March 2009 (UTC) Again, there is no policy that says verifiable and reliable sources must be peer-reviewed. In any event, what is your reaction to the peer-reviewed science? Your personal POV that expansion is impossible, even though it has been oberved on Ganymede, does not justify the supression of information. As far as your question is concerned, it's irrelevant in terms of NPOV and information suppression concerns. Expansion does not violate the conservation of mass in any possible way and your claim that it does is unsourced and irrelevant to NPOV and information suppression concerns.Sophergeo (talk) 09:44, 21 March 2009 (UTC) Please stop assuming I am lying to you, that is assuming WP:BADFAITH, which is against policy. Since you haven't found them yourself, here you go: WP:RS#Extremist and fringe sources goes for the Journal of Scientific Exploration and related fringe sources. Wikipedia:Reliable source examples describes scientific articles and advice; it is this that is used as the basis for controversial topics. It addresses what sources are reputable and what aren't. Expansion has not been observed on Ganymede, it is a conjecture at best. My statement is not that expansion is that impossible, but is very close: it is that mass must be conserved. Please tell me why you think it doesn't, with a source that states why. Either it has to add mass from the inside or decrease in density. I gave a source earlier, please look and stop assuming bad faith. It is not a point of view, it is an established fact that your additions will have to deal with. Either deal with it or relegate yourself to supporting what opposes the foundation of physics. Awickert (talk) 09:56, 21 March 2009 (UTC) I am not assuming you are lying and that is a false accusation. What am I assuming you to be lying about? This has nothing to do with lies. This has to do with NPOV and suppression of information. What is your reaction to the peer-reviewed science posted above? Your personal POVs do not justify the suppression of peer-reviewed science to the contrary.Sophergeo (talk) 10:10, 21 March 2009 (UTC) You assumed I was lying about Wikipedia policy about reliable sources: I told it to you, you refuted me, and I told it to you with sources. You do not want my opinion, otherwise you would respond to it, so I will not give you mine on your new sources until you become responsive. It seems that no matter what I say, I get nothing but your punchline about suppression of information and my "Unsourced POV". I have sourced my information, so it seems you are not reading what I write. I have nothing to assume but that, in spite of your extensive research, you are either unable or unwilling to explain how this theory holds up to basic physical principles. It is the responsibility of the contributor to show that what they add is correct: until you do this, for example, but answering my conservation of mass question with reference to your sources, this useless conversation is over and I will not allow any addition to this article beyond a link to Expanding Earth on "See Also". Feel free to add whatever you want to the Expanding Earth article, so long as you don't make it a WP:POVFORK. Awickert (talk) 10:21, 21 March 2009 (UTC) I didn't assume you were lying about Wikipedia policy and that is a false accusation. Where in Wikipedia does it say reliable sources must be peer-reviewed? And what is your reaction to the peer-reviewed science? The continuity equation is a red herring and has less than zero to do with subduction. Furthermore, it does not justify information suppression.Sophergeo (talk) 10:27, 21 March 2009 (UTC) Jump up 4 comments, you'll find them. I'm replying because I think we might get somewhere this time; thank you for addressing cntinuity. The continuity equation, as a matter of fact, has a lot to do with subduction: there is no way of modeling subduction and mantle flow without it. It has a lot to do with the expanding earth because there must be a way for mass to be conserved with volume change. Unless you can answer how that may be, as it is a fundamental question about the expanding Earth, I suppose I'll have to claim that you're suppressing laws of nature in purporting this as a theory of anything but a fringe scientific following. Awickert (talk) 10:39, 21 March 2009 (UTC) A personal POV can never justify the abandonment of the NPOV policy and the suppression of information that might contradict what we personally believe to be true and dear.Sophergeo (talk) 10:44, 21 March 2009 (UTC) Sorry - as it seems like you (a) don't read my comments, (b) can't answer a direct question, (c) repeat yourself incessantly, and (d) can't differentiate between physical law and point of view; I guess I can't help you here. Conclusion based on (lack of) discussion: Expanding Earth is fringe, on basis of violation of physical principles. Good luck in life. Awickert (talk) 10:50, 21 March 2009 (UTC) Your unsourced POV description of the peer-reviewed science published in Nature and Science as "fringe" cannot justify information suppression or a violation of the NPOV policy.Sophergeo (talk) 10:58, 21 March 2009 (UTC) Those papers were in the 50's and 60's, when we had no clue what was happening and therefore couldn't constrain much of anything; they are notable, and are accorded due weight in the Plate Tectonics article. Present-day expanding Earth theory is fringe, and even you can't explain how it doesn't violate the laws of physics. Awickert (talk) 11:05, 21 March 2009 (UTC) Plate tectonics and subduction papers are from the 50s and 60s well. That doesn't justify suppression of information. What about the peer-reviewed papers that aren't from the 50's and 60's? Yet another red herring that cannot justify information suppression. There is no weight in this article given to criticism of subduction which is why I challenge it's NPOV.Sophergeo (talk) 11:18, 21 March 2009 (UTC) (outdent) Yes, but since the 1960's, plate tectonics has been developed and observed, while the expanding Earth was left behind. It has no mechanism and no proposed way of obeying physical laws. Before we knew what we know today, it was more mainstream; there are no recent articles in mainstream reliable geology journals such as Geology, GSA Bulletin, JGR, GRL, Tectonophysics, etc. about it. None. But there are tons of articles on observations of plate tectonics, each of which would by definition refute what you say. These articles have a mechanism, have observations, and obey all the necessary physics. They take the planet back before Pangaea, something that the Expanding Earth often fails to do, and match observations of continental growth and assembly. There is really no weight in the geological community given to criticism of subduction, and so if proportional weight must be given to expanding Earth, then that proportional weight would equate to a "see also" link on the bottom. Awickert (talk) 11:31, 21 March 2009 (UTC) Irrelevant to the discussion of NPOV and suppression of information. I'm not saying you are wrong or that anybody is wrong. I am saying that the two sides are to be presented with NPOV and the interpretations are free and to be discussed. That is the spirit of NPOV. And that is the purpose of an encyclopedia. The purpose of an encyclopedia is not to suppress information we disagree with.Sophergeo (talk) 11:50, 21 March 2009 (UTC) Nothing is being suppressed here. The key is in Awickert's use of the phrase 'proportional weight' and it is entirely relevant to the NPOV discussion. Mikenorton (talk) 14:41, 21 March 2009 (UTC) Why do you define over 37 verifiable and reliable peer-reviewed sources as "nothing"? Propoportional weight does not mean zero weight or justify information suppression.Sophergeo (talk) 17:11, 21 March 2009 (UTC) I removed the POV template, it is itself POV. Sophergo claims there are plausible scientific alternatives to plate tectonic theory and wants them in the article. This (subduction) is a scientific theory that is heavily and very profoundly established in the scientific community. To claim otherwise would require some good sources, and I see so far no sources that count as good in this subject. One cannot simply take some writings by a couple of crankpots and suppose there ideas should be mentioned into this type of article. What is needed for an alternative to become worthy of mentioning is a reliable source. I suggest the template will be put back (or a sentence about the alternative inserted into the article) when Sophergo comes with a quote from an ontopic scientific (i.e. Earth sciences) handbook published after 1995, that is well-known and used in scientific education, or an article published later than 1995 in either one of these journals: Tectonophysics, Journal of Structural Geology, Earth and Planetary Science Letters, Geophysical Research Letters, Tectonics or Geology, that explicitly states: A) that there is a plausible alternative hypothesis to subduction, B) that alternative can also explain observations from metamorphic and igneous petrology, deep seismics, structural geology, geodesy and other geophysic methods that support subduction. If Sophergo is unable to do so I will assume he is trying to POV-push pseudoscience into an article on a scientific subject. If he keeps putting the template or the alternative hypothesis back without giving sources I will assume bad faith (i.e. vandalism) and propose his account to be blocked. In good faith, Woodwalker (talk) 17:12, 21 March 2009 (UTC) Please do not remove the POV tags until the NPOV dispute is resolved. Sometimes people have edit wars over the NPOV dispute tag, or have an extended debate about whether there is a NPOV dispute or not. In general, if you find yourself having an ongoing dispute about whether a dispute exists, there's a good chance one does, and you should therefore leave the NPOV tag up until there is a consensus that it should be removed. The fact that subduction is "profoundly estblished" is irrelevant and does not justify information suppression of widely held verifiable of minority views which happen to contradict the POV we happen to believe to be dear and true. This is an encylopedia, not a place to censor or suppress information we personally disagree with. Peer-reviewed science shgould not be considered "crackpot" simply because we disagree with it and wish to suppress that information. Suppression of verifiable and reliable peer-reviewed information violates NPOV and is against the spirit of Wikipedia. If you are unfamiliar with NPOV please see the section on NPOV. Sophergeo (talk) 17:27, 21 March 2009 (UTC) It is not because we disagree with it; it is because (a) it is supported by a tiny fringe: WP:WEIGHT would give it little to no room in the article, and none of the journals you cite for the 1990's and later are reputable on tectonics, and (b) you refuse to acknowledge any issues in your argument for it, or directly engage in discussion in any way. If we go on the strength of the argument, it doesn't stand up to basic scientific scrutiny. If we go on the weight of the opinions and sources compared to mainstream, it wouldn't get more than a "See also" link. I'm getting tired of this continued "information suppression" boondoggle: either you engage in productive conversation here, or please stop repeating yourself via what looks like copy-paste. We all read it the first time. Awickert (talk) 17:41, 21 March 2009 (UTC) No weight = information suppression. [Infomation Suppression] (edit conflict)Sopergeo it is you that are unfamiliar with NPOV, you have made that abundantly clear over the past few days on this and the Talk: Mantle (geology) page. You don't seem to have read past the first few sentences, particularly you do not appear to have read the section on 'Undue weight', which is the most relevent part for this discussion. Mikenorton (talk) 17:43, 21 March 2009 (UTC) No weight is not undue weight. It is information suppresion and a violation of NPOV.Sophergeo (talk) 17:50, 21 March 2009 (UTC) @Sophergeo: And that is exactly why I suggested you'd supply us with such peer-reviewed scientific sources, because up until now, you didn't. I gave you the names of the magazines that will do for this field of research, and asked for publications after 1995 in those magazines. If there is a scientific alternative to subduction, it must have been reported in one of these magazines. Please understand we are trying to provide people with information on a geoscientific subject here. We do this by mentioning all relevant scientific views on the subject in the article, no less, no more. When you do not have any sound reference to show a view is scientifically relevant, it should not be mentioned in the article. So get into a library and check the magazines I named instead of keeping others from their work with stating guidelines (we all know them) or lists of outdated and off-topic publications that do not count as reliable sources on the subject. Woodwalker (talk) 17:44, 21 March 2009 (UTC) There is no Wikipedia policy that says verifiable and reliable information has to be from the dates and publications you specifySophergeo (talk) 17:50, 21 March 2009 (UTC) Please stop misquoting Wikipedia policies, it is a form of Wikilawyering. I just ask you to give reliable sources for your statement that there is a sound scientific alternative for subduction. The magazines I named are all reliable sources for this field of research. If you want to prove experts this alternative is scientifically existing, these are the magazines to head for. Woodwalker (talk) 17:56, 21 March 2009 (UTC) What Wikipedia policy did I misquote? Please do not make personal attacks. The reliable sources are posted above.Sophergeo (talk) 17:59, 21 March 2009 (UTC) Please at least look at the links I gave you to Wikipedia policy. You habit of repeating yourself and quoting policy is aggressive and unproductive. The Journal of Scientific Exploration, at least, sure isn't "reliable". You also summarily dismissed my comments on your first round of sources, and continue refuse to address them, so I assume my opinion on the new ones will be equally irrelevant "POV". This debate could be solved if you engage in it and explain how this is mainstream and physically plausible, which would make it be something other than bogus fringe. Awickert (talk) 18:09, 21 March 2009 (UTC) @Sophergeo: Well, in this case you misquoted the definition of a personal attack, for example. I will no longer react in this discussion since you seem not to listen to my advice (and that of others). As soon as you supply us with reliable sources I will be ready to help you again. Please be aware I reported your edits on the noticeboard for editwars. Woodwalker (talk) 18:16, 21 March 2009 (UTC)

RFC notification

Resolved

 – 3 contributors banned as master and socks. RFC closed. Awickert (talk) 20:40, 23 March 2009 (UTC)

I have initiated a request for comment on the Expanding Earth hypothesis at Talk:Expanding Earth#Request for Comment: Expanding Earth and Plate Tectonics. Please leave a comment there, or a statement if you were involved in the debate. Thank you, Awickert (talk) 05:08, 22 March 2009 (UTC)

Killer Volcanoes! Slamming Plates! Deep Biology! And what is an "alalog"?

I did some bold editing today to clean up misspelled words, reduce some jargon, and delete some sensationalism from the article.

I completely removed a line, unsourced, that claimed something along the lines of..."because subduction zones are cold....they almost certainly contain the deepest living things on the planet" as being someone's speculative opinion. See the WP for original research and weasel words before restoring that to the article. —Preceding unsigned comment added by Geogene (talk • contribs) 23:01, 5 June 2009 (UTC)

New article for Subduction volcano

Should there be a new article for subduction volcanoes? I think it is notable enough to deserve its own article. --The High Fin Sperm Whale (Talk · Contribs) 20:02, 20 November 2009 (UTC)

O.K WHO IS THE PERSON THAT SAID THIS OF COURSE THERE SHOULD BE ONE. :(
—Preceding unsigned comment added by 205.124.153.226 (talk) 21:37, 2 December 2010 (UTC)

Change to SVG version of diagram

I reverted a change to the SVG version of file:subduction.png, because I don't honestly see any improvement in general and the internal structure of the accretionary prism looks all wrong to me. Mikenorton (talk) 23:46, 18 March 2014 (UTC)

Hi Mikenorton,first of all thank you for your note. Could you please be a little more precise, I´ll make subsequent changes to the file according to your specifications. Thanks in advance --MagentaGreen (talk) 09:16, 24 March 2014 (UTC)

Asthenosphere

Asthenosphere is labeled as 'molten' in the top image which is incorrect, I added a note in the caption but don't know how to edit the image Dave mathews86 (talk) 04:13, 17 October 2016 (UTC)

@Dave mathews86: I have edited the image. Please ping me if you would like to see any additional changes. I would be glad to make any! KDS4444 (talk) 01:36, 29 October 2016 (UTC)

@KDS4444: I wouldn't really call it semi-solid. "Mostly-solid" is probably a better term. Polyamorph (talk) 13:43, 27 July 2017 (UTC)

Done. KDS4444 (talk) 21:25, 27 July 2017 (UTC)

For information, see https://deepcarbon.net/feature/folly-404-wikipedia-lesson#.WZxfgSiGOuU (The Folly of the 404: A Wikipedia Lesson). Polyamorph (talk) 16:46, 22 August 2017 (UTC)

Global Convergent Plate Margins... image

Typo in image (ConMarRJS.jpg) description. "subduction ones" should be "subduction zones". Don't know how to change the image proprely. Menswear (talk) 13:48, 25 February 2018 (UTC)

Active subduction at transform margins?

Following the recent edits (that I reverted) I took a look at the western Aleutian Arc and found that most of the papers do not support "active" subduction at this margin although remnant subduction is a possibility, from a time when the geometry was different - see Koulakov et al. 2011. Are there other clearer examples? Mikenorton (talk) 00:22, 25 February 2020 (UTC)

Carbonate and subduction

The section on modern-style subduction has the curious paragraph:

Geophysicist Don L. Anderson has hypothesized that plate tectonics could not happen without the calcium carbonate laid down by bioforms at the edges of subduction zones. The massive weight of these sediments could be softening the underlying rocks, making them pliable enough to plunge.

The supporting source is by a doctor of "holistic science" and is not previewable on Google Books or Online Library. I can buy the idea that carbonates alter the ductility of oceanic crust, if given some better sources. I can find none on Google Scholar. That it is the weight of carbonate sediments that increases ductility beggars belief. Should this paragraph just go? --Kent G. Budge (talk) 18:23, 3 December 2020 (UTC)

yes, it is unreliably sourced, pseudoscience nonsense and should go. The density of carbonate rocks (~2.7) is lower than oceanic crustal rocks (~3.1 to 3.4) so the latter have the greater "massive weight". The idea that the carbonates increases the ductility of the subducting slab is just superfluous fantasy. Wholesale, through and through mixing of the two does not happen. Plantsurfer 18:53, 3 December 2020 (UTC)

It certainly sounded fringy, but I wondered if there was some truth there that had gotten badly garbled. If not -- removing it. --Kent G. Budge (talk) 19:23, 3 December 2020 (UTC)

The theory exists albeit the source used to mention it may be flawed. Don L. Anderson's carbonate theory is however likely to be obsolete by now, as this was one of the first theories proposed to explain the orogin of subduction and has since then not been followed up. Lappspira (talk) 22:22, 3 December 2020 (UTC)

Confused

I'm a tad confused, wondering if we could explain better or elucidate more: I assume the "crust" layers are lighter than the stuff underneath; that's why the "float" or "drift" around. However, article says opposite, oceanic crust is denser than the stuff underneath.

• If it is denser, why does it "float"? Why doesn't it just sink where it is (in the middle of the ocean say) and the lighter stuff below well up?
• Is the oceanic crust denser than the continental crust? I would guess the continental crust is denser or at least heavier.(?) If continental was heavier, why doesn't it ride under, and let the lighter stuff go over?
• Why the emphasis on slab pull? Let's look at north america, for example. It is approximately 7000 km from mid atlantic ridge to west coast subduction zone. Does the 700km subducting slab pull the 7000 km plate along? What keeps the plate from splitting apart? ("stretching like taffy") Why is slab pull more prominent that mid-ocean push? or the push from the convection current? (the convection current has 7000km to work on the plate, with no worries about the plate pulling apart)

Feldercarb (talk) 14:56, 25 July 2021 (UTC) Feldercarb (talk) 15:05, 25 July 2021 (UTC)

Oceanic crust and lithosphere are denser than continental crust and lithosphere. That is why it can subduct. Metamorphism during subduction makes oceanic crust even more denser. Where does the article say subduction is pulling North America from the MAR? You have many questions but if you feel the article is misleading or wrong please refer to specific parts and we can discuss them here. Remember this is not a forum and the aim is to improve the article, not do science by our own. Mamayuco (talk) 15:23, 25 July 2021 (UTC)