Talk:Permian–Triassic extinction event/Archive 3

West Falklands Impact Hypothesis

I found This article about a hypothesis that there is an impact crater sufficient to have caused this event. The link is from the funder so it's not objective, but it points to an upcoming peer reviewed report in the journal Terra Nova. Can anything be added to this page about the West Falklands hypothesis or should it wait until the paper comes out? 167.201.241.175 (talk) 13:03, 12 June 2017 (UTC)

References

Chart at the top of the article

I think the caption for this chart might need a little more explanation. Can the vertical axis be labelled? I can infer the trend indicated in the chart, but I can't say I know exactly what it is saying. Regards, PDCook (talk) 17:26, 27 March 2010 (UTC)

Picture of supercontinent and areas marked

The supercontinent picture is a bit misleading because the text next to it says that the continents are labelled. However, Australia is missing. Also, India, which is a nation and not a continent, is labelled. Is there a way to fix this? —Preceding unsigned comment added by Montreux (talk • contribs) 05:03, 19 April 2010 (UTC)

There is no problem with that picture, 1. Australia is there, 2. India is also a geological continent. Rursus dixit. (^mbork³!) 20:01, 14 June 2010 (UTC)

Copyright problem removed

50 or more portions of this article duplicated other source(s). The material was copied from: (see below). Infringing material has been rewritten or removed and must not be restored, unless it is duly released under a compatible license. (For more information, please see "using copyrighted works from others" if you are not the copyright holder of this material, or "donating copyrighted materials" if you are.) For legal reasons, we cannot accept copyrighted text or images borrowed from other web sites or published material; such additions will be deleted. Contributors may use copyrighted publications as a source of information, but not as a source of sentences or phrases. Accordingly, the material may be rewritten, but only if it does not infringe on the copyright of the original or plagiarize from that source. Please see our guideline on non-free text for how to properly implement limited quotations of copyrighted text. Wikipedia takes copyright violations very seriously, and persistent violators will be blocked from editing. While we appreciate contributions, we must require all contributors to understand and comply with these policies. Thank you. J. Spencer (talk) 00:08, 21 October 2010 (UTC)

While checking some rewording, I found that two chunks of text were copy-and-paste jobs, mostly from http://math.ucr.edu/home/baez/extinction/, but with some lines from http://www.santafe.edu/media/workingpapers/99-12-079.pdf woven in as well. What appears to have happened is the article The Big Five was merged to several extinction pages in September 2008 (in this page's case this edit) without it being known that the merged article was a copyvio.

After considering, I removed the chunks that were copyvios instead of rewriting as the first chunk was largely redundant with other text, and the second chunk had been slightly modified and was no longer accurate. J. Spencer (talk) 00:08, 21 October 2010 (UTC)

How sure are you about this? I know the Baez site has borrowed significantly from Wikipedia in the past (and hence the copying might go in the other direction). In addition, someone who appears to have a vested interest in that site has on various occasions added material to Wikipedia, so it may have been added by the copyright owner. So I'd want to look closely before declaring an infringement. Of course, if it can be rewritten / replaced / removed without harming us then that is probably all for the best regardless. Dragons flight (talk) 00:21, 21 October 2010 (UTC)

Here's a random pre-July 2008 (when "The Big Five" was started here) pull from Internet Archive; and here is the site today. The text for the Permian-Triassic, Late Devonian, and Ordovician extinctions are exactly the same as they are now, so the Baez site has to be the originator in this case. J. Spencer (talk) 00:31, 21 October 2010 (UTC)

impact event?

What about the Hudson Bay impact? It is certainly large enough to have caused a mass extinction on a scale far exceeding the demise of the dinosaurs. Does anyone know when the Hudsom Bay impact occurred? —Preceding unsigned comment added by 76.28.177.80 (talk) 16:02, 23 October 2010 (UTC)

If a person takes the time and effort to read through and look at the numerous detailed papers and geologic maps that has been published by geologists and other Earth scientists for the Hudson Bay shorelines and region, they would find that there is more than enough hard data to completely refute any ideas about the Nastapoka Arc being part of enormous extraterrestrial impact structure. The fact of the matter is that many geologists have looked long and hard for any evidence of impact deformed and brecciated rock, shocked quartz, shatter cones, high pressure mineral polymorphs, impact melt sheets and/or dikes, and impact-related pseudotachylytes associated with the Nastapoka Arc. Despite repeated efforts to find it by geologists and expectation that it would be found, such evidence has been found to be completely absent. Instead, they have found that local and regional structure, stratigraphy, and other aspects of the geology of the Nastapoka Arc soundly refute the theory that it was created by an extraterrestrial impact and solidly demonstrate the fictional and imaginary nature of a hypothesized "Hudson Bay Impact." The question about the age of the "Hudson Bay Impact" lacks any answer because the "Hudson Bay Impact" never occurred in the first place. When looking at Hudson Bay and Nastapoka Arc with Google Earth, a person has to understand that there are many other geological processes in addition to extraterrestrial impacts that are capable of producing arcuate geological structures and landforms. Go look at:

1. 2. Is there a large impact structue on the SE margin of Hudson Bay, Canada?

2. Eaton D. W. and F. Darbyshire, 2010, Lithospheric architecture and tectonic evolution of the Hudson Bay region. Tectonophysics. v. 480, pp. 1–22.Paul H. (talk) 05:28, 24 October 2010 (UTC)

Using abbreviations without explanations.

for instance - what is "Ma"?

However, a study of uranium/lead ratios of zircons from rock sequences near Meishan, Changxing, Zhejiang Province, China[3] date the extinction to 251.4 ±0.03 Ma, with

Ma is "megaannum", or "million years". It's got a metric prefix, and is slightly more flexible than "million years ago" because the "ago" isn't explicitly part of the name (i.e., you can use it for comparisons, like "A was found in rocks 6 Ma older than B", which is clumsier when you've got to work around "ago"). J. Spencer (talk) 00:32, 18 November 2010 (UTC)

"Mya" is much clearer. --Michael C. Price ^talk 01:05, 18 November 2010 (UTC)

I don't have a horse in that race; I'm just happy when people pick one and stick with it! J. Spencer (talk) 01:16, 18 November 2010 (UTC)

Having said that, the article uses both formulations, and really ought to be standardized. J. Spencer (talk) 17:03, 20 November 2010 (UTC)

Impact Origin of the Gulf of Mexico

The AAPG essay / commentary, Stanton (2002), about the Gulf of Mexico being an impact crater is not only very speculative, but it is also very badly flawed and sloppy in terms of its scientific content and interpretations. It relies too heavily on very dated, if not antiquated, reference material, including a 1979 textbook. This essay simply ignores the overwhelming number of more recent peer-reviewed publications that contain geophysical and geological data and research that soundly refute specific interpretations made by it along with the idea Gulf of Mexico being an impact crater. For example, Viele et al. (1989) and Nichlas et al. (1989) summarizes decades of research that readily refutes the idea that either fold belts of the Ouachita orgeny or the metamorphism of their associated Paleozoic rocks could have possibly been created by an asteroid impact of any magnitude. They are the result of nonimpact tectonic processes that not only acted over tens of millions of years but also started hundreds of millions of years before the Permian–Triassic extinction event. In another case, there exists ample published geophysical and geological research, as summarized by Goldthwaite (1991) and Sawyer et al. (1991), that demonstrates that the central uplift, which Stanton (2002) claims to exist in the center of the Gulf of Mexico, is completely imaginary. The idea that the Gulf of Mexico is an impact basin and that there are seriously problems with a plate tectonic explanation of its origin is a dead issue among geologists in general as illustrated by the papers by Dickinson and Lawton (2001) and Galloway (2008). Stanton (2002) is so extremely badly researched and argued that it fails to provide a credible case for the Gulf of Mexico being an impact crater.

References Cited:

Dickinson, W. R., and T. F. Lawton, 2001, Carboniferous to Cretaceous assembly and fragmentation of Mexico. Geological Society of America Bulletin. v. 113, no. 9, pp. 1142–1160.

Goldthwaite, D., ed., 1991, Introduction to Central Gulf Coast Geology, New Orleans Geological Society, New Orleans, Louisiana.

Galloway, W. E., 2008, Depositional evolution of the Gulf of Mexico sedimentary basin, in K.J. Hsu, ed., pp. 505-549, The Sedimentary Basins of the United States and Canada, Sedimentary Basins of the World. v. 5, Elsevier, The Netherlands.

Nicholas, R. L., and D. E. Waddell, 1989, The Ouachita system in the subsurface of Texas, Arkansas, and Louisiana, in R. D. Hatcher, Jr., W. A. Thomas, and G. W. Viele, eds., pp. 661-672, The Appalachian-Ouachita Orogen in the United States: The Geology of North America, v. F-2. Geological Society of America, Boulder, Colorado.

Sawyer, D. S., R. T. Buffler, and R. H. Pilger, Jr., 1991, The crust under the Gulf of Mexico basin, in A. Salvador, ed., pp. 53-72, The Gulf of Mexico Basin: The Geology of North America, v. J., Geological Society of America, Boulder, Colorado.

Stanton, M. S., 2002, Is the Gulf's Origin Heaven Sent? American Association of Petroleum Geologists. Tulsa Oklahoma. [Stanton (2002) PDF file], [Stanton (2002) Web Page]

Viele, G. W., and Thomas, W. A., 1989, Tectonic synthesis of the Ouachita orogenic belt, in R. D. Hatcher, Jr., W. A. Thomas, and G. W. Viele, eds., pp. 695-728, The Appalachian-Ouachita Orogen in the United States: The Geology of North America, v. F-2. Geological Society of America, Boulder, Colorado

Why not just edit the article to include this information? J. D. Crutchfield | Talk 20:17, 9 June 2014 (UTC)

Science News resource

Acidifying oceans helped fuel mass extinction; Great die-off 250 million years ago could trace in part to waters' change in pH by Alexandra Witze October 8th, 2011; Vol.180 #8 (p. 10) Science News 99.35.15.199 (talk) 00:55, 10 October 2011 (UTC)

It would be better to consult the full paper instead a popular science article. The paper discussed in this article is:

Montenegro, A., P. Spence, K. J. Meissner, M. Eby, M. J. Melchin, and S. T. Johnston (2011), Climate simulations of the Permian-Triassic boundary: Ocean acidification and the extinction event. Paleoceanography. vol. 26, no. PA3207, 19 pp. doi:10.1029/2010PA002058. Paul H. (talk) 11:59, 10 October 2011 (UTC)

paper published online August 2 in Paleoceanography per link. 97.87.29.188 (talk) 20:55, 10 October 2011 (UTC)

Algeo et al.

A NSF press release announces a paper by Algeo et al. which will be relevant to this article: presumably time is needed for evaluation. . dave souza, talk 09:25, 21 February 2012 (UTC)

Add?

• Life in the Sea Found Its Fate in a Paroxysm of Extinction April 30, 2012 New York Times 99.109.124.95 (talk) 23:51, 8 July 2012 (UTC)

That's no doubt important work. But it would be better not to rely on a New York Times summary for it, even trustworthy as the Times generally is. Looie496 (talk) 16:14, 9 July 2012 (UTC)

Suggestions, Looie496? 99.181.143.128 (talk) 03:38, 10 July 2012 (UTC)

This paper, one of the two cited in the NYT article, would be an excellent source. It cites the other paper, and a PDF version is freely downloadable online. Looie496 (talk) 05:12, 10 July 2012 (UTC)

New research.

I came across this new research into why life took so long to recover from the extinction. According to this much of the planet was simply too hot for life to survive for millions of years.

http://www.sciencedaily.com/releases/2012/10/121018141844.htm

Could this be mentioned in the article? G-13114 (talk) 12:18, 19 October 2012 (UTC)

Science Daily is essentially a newspaper, and therefore not a good source for Wikipedia science article, but the Science paper that the story is based on would be usable (http://www.sciencemag.org/content/338/6105/366.abstract), or http://www.sciencemag.org/content/338/6105/336.summary, which is a perspective piece about it. Looie496 (talk) 14:43, 19 October 2012 (UTC)

In 2003, Dr. Peter Ward observed, that global atmospheric oxygen levels plummeted, from Carboniferous / early Permian levels near 30%, to a third of that, from the later Permian, through the Triassic, and into the Jurassic. Those oxygen levels are plotted in figure two, of the following article:

http://www.pnas.org/content/96/20/10955.full

By c.300Ma, Pangea had assembled. Major mountain ranges eroded through the Permian. Then, Pangea began to break apart. Massive rifting, with immense flood basalts, occurred c.260Ma in China (Emeishan traps), c.250Ma in Siberia (Siberian traps), and c.200Ma with the opening of the Atlantic (Central Atlantic Magmatic Province). Those repeated rifting events coincide with repeated mass extinctions, and repeated falls in global atmospheric oxygen levels. Global temperatures rose, much of Pangea desertified, flora evidently died back. The global ecosystem did not begin to recover, until the Jurassic, after 200Ma, and after the last major episode of rifting. Dinosaurs, evolved with bird-like air sac respiratory systems, could cope with lower levels of oxygen, and began to dominate. Meanwhile, mammals, with less efficient lungs, were required to remain small. A prolonged period of rifting, breaking apart Pangea, with immense flood basalt eruptions; and resulting low levels of oxygen; and dinosaurs having better bird-like lungs; can explain the prolonged period of mass extinctions from c.260-200Ma, the rise of dinosaurs, and the relegation of mammals to small sizes & secondary niches. Mainstream citable sources could include Nature:

http://www.nature.com/news/1998/031103/full/news031103-7.html

as well as the documentary series Miracle Planet (episode 4). 66.235.38.214 (talk) 15:32, 24 October 2012 (UTC)

http://www.sciencedaily.com/releases/2007/10/071025091047.htm

http://www.sciencedaily.com/releases/2011/05/110505103339.htm

Evidence for accelerating global extinctions from 270-250Ma, repeating 200Ma; and for Parareptiles struggling to survive, through that entire epoch, until vanishing 200Ma. Ipso facto, the period 270-200Ma may have been a single prolonged epoch of massive magmatism amidst the rifting apart of Pangea. The massive volcanisms repeatedly plunging the planet into greenhouse conditions, de-oxyifying the oceans, and atmosphere, without sustained recovery, until the Jurassic. 66.235.38.214 (talk) 17:29, 24 October 2012 (UTC)

Changes in marine ecosystems

Prior to the extinction, approximately 67% of marine animals were sessile and attached to the sea floor, but during the Mesozoic only about half of the marine animals were sessile while the rest were free living.

Can't access the reference, but I was wondering if it really said 67% and not two-thirds, which seems a more likely approximation. Ssscienccce (talk) 08:51, 5 November 2012 (UTC)

You can often find access to a paper by searching in Google Scholar even if it is paywalled by the publisher. I looked at the cited source and I don't believe it actually gives numbers for this at all -- I think the actual source for the numbers is probably this PNAS paper, which is publicly accessible -- see figure 1. Looie496 (talk) 23:00, 5 November 2012 (UTC)

Seriously? Don't these two realize that "approximately 67%" and "two-thirds" are essentially equal portions? Two-thirds = 66.66% Round that to the nearest whole number and you get approximately 67%. [Forgot to sign this comment earlier.] J. D. Crutchfield | Talk 19:02, 10 June 2014 (UTC)

Volcanism -reference does support

Recent climate models suggest such a rise in CO2 would have raised global temperatures by 1.5 to 4.5°C (2.7 to 8.1°F), which is unlikely to cause a catastrophe as great as the P–Tr extinction.[93]

The reference cited does back up the non italic part of this sentence, but not the rest. Is this just the author's opinion, original research, or has a second citation, which does support the last part, been mistakenly left out? Common sense isn't enough, please add a source which does back up the claim that a 1.5 to 4.5°C rise "is unlikely to cause a catastrophe as great as the P-Tr extinction". 82.25.174.154 (talk) 22:46, 24 February 2013 (UTC)

I agree. It is as if the CO2 link is artificially inserted. The Permian extinction was mostly a sulfur poisoning event. As we know volcanoes produce lots of sulfur, especially when they are huge and go on for almost a million years. So why create an artificial global working/bacteria reason for sulfur? Marcperkel (talk) 02:49, 18 March 2014 (UTC)

If the second part of the assertion is not supported by the authority cited, the sentence violates WP:SYNTH and should be modified or removed. I don't know enough to edit it intelligently, but perhaps 82.25.174.154 or @Marcperkel: would kindly do it? J. D. Crutchfield | Talk 20:13, 9 June 2014 (UTC)

Possible relevant reference

I came across this http://www.readcube.com/articles/10.1038/ngeo154?locale=en which casts doubt on the theory that hydrogen sulphide emmissions could have caused the mass extinction. Maybe this could be included in the article? But unfortunately you can only see part of it without a subscription. G-13114 (talk) 18:24, 6 October 2013 (UTC)

Interesting, but this is a study from 2008 which suggest the ozone layer stayed intact. But since 2008 studies have shown that methane potential is higher with implications for stratospheric ozone. Prokaryotes (talk) 18:31, 6 October 2013 (UTC)

Great Dying

This has been the common name for as long as I can remember. We have multiple WP:RS sources, ranging from National Geographic to COSMOS. Why would anyone revert such a perfectly reasonable and accessibility-improving addition to the intro? I was quite shocked to see such a speedy revert. — Preceding unsigned comment added by 202.166.31.191 (talk) 13:11, 1 April 2014 (UTC)

"see map above"

"The continents of the end-Permian and early Triassic were more clustered in the tropics than they are now (see map above),"

This sentence, in the "Methane hydrate gasification", says "see map above", but there is no map above. There is one map on the page, lower down, but doesn't seem to be the one this is referring to. Was the map removed? Was this text copied from elsewhere?

70.36.190.2 (talk) 00:56, 10 April 2014 (UTC)

Removed the (see map above) bit - don't know the explanation ... but there is no map above. Thanks for noting that. Vsmith (talk) 03:22, 10 April 2014 (UTC)

I suspect "See map above" was referring to the map of Pangaea, which appears below the former reference. The present map, however, does not show the location of tropics. We can speculate that the equator is supposed to be across the middle of the map, and that the tropics would lie some distance above and below that; but the map as it stands doesn't contain enough information to support the statement. It would be useful, if somebody wanted to take the trouble, to substitute a map that indicates the equator and the tropics, and then to restore the reference to it in the text. J. D. Crutchfield | Talk 19:49, 9 June 2014 (UTC)

Gibberish

The sub-section "Impact event" contains the following:

One attraction of large impact theories is that theoretically they could trigger other cause-considered extinction-paralleling phenomena . . . .

What on earth are "cause-considered extinction-paralleling phenomena"? Would somebody who knows what this sentence is trying to say translate it into English, please?

I'll also point out that, as it now stands, the sentence attributes the power of causing such phenomena to large theories, rather than to large impacts. J. D. Crutchfield | Talk 19:40, 9 June 2014 (UTC)

It is technically known as bollocks. Suggest you delete it, per WP:Bold Plantsurfer (talk) 19:46, 9 June 2014 (UTC)

Ha ha. The trouble is, I think it's supposed to mean something legitimate: that large-impact theories are attractive because large impacts could trigger other phenomena that are considered potential contributors to the mass-extinction, so that large-impact theories can wrap up multiple potential causes in one package. I just don't know enough about the subject to be confident that that is true, or that it's what the original writer meant to say, so I don't want to put my interpretation into the article. J. D. Crutchfield | Talk 19:08, 10 June 2014 (UTC)

I'd like to know what Ma is an abbreviation for? I've never seen it before and can't find a reference on the internet; one site lists 750 different things it could be. — Preceding unsigned comment added by 98.215.250.39 (talk) 15:26, 17 October 2014 (UTC)

Ma is the standard abbreviation that Earth scientists use for megaannum, which is a unit of time equal to one million years. For a discussion of its usage go see Discussion of GSA Time Unit Conventions. Paul H. (talk) 21:15, 17 October 2014 (UTC)

Individuals

Trying to bring this into perspective for people. When you say that 57% of 'families' went extinct, either it's very abstract for them, or they think of 'family' like a mother and father and kids, and they all died. I hear people say 96% of species went extinct, but apparently that's only marine species. And so they tend to think only 96% of the individual animals died. Which is a bad thing to happen, but not nearly accurate.

So, how many individuals died? If 96% of all species went extinct, that means 100% of the individuals in 96% of the species died. Probably a lot of individuals in the surviving 4% of species also died, but less than 100% for each of these species. So I'm guessing, something like 99.9% of all individuals died, but that's just a guess. That number would really bring the PT extinction into perspective. — Preceding unsigned comment added by 75.101.22.253 (talk) 21:57, 4 October 2014 (UTC)

Families and species are the correct biological terms to use, and I have updated it so they both contain links to the relevant pages explaining what they mean in regards to  ::taxonomy.

Putting a number on the % of individuals dying would be pretty much impossible, especially in such an extinction which has been shown to be very selective.GeoSeal (talk) 21:25, 5 March 2016 (UTC)

Resolving conflicting sections (2016)

I made a small edit to the Causes/Methane hydrate gasification section, to try to resolve the conflicting content, specifically the claim that no other proposal could offer a sufficient source of CO2, as the claim was based on work from the early & mid 1990s, and is now out of date considering the proposal that volcanism emerging under coal beds and carbonate rocks would emit far more CO2 than the magma itself, which the 1995 reference only considered. (The article, ref. 122, "Dissociation of oceanic methane hydrate as a cause of the carbon isotope excursion at the end of the Paleocene", Dickens et al, is found behind a paywall when following the links in the ref section, but I found it as an image (non-character) pdf here: www.whoi.edu/cms/files/dickens95po_129844.pdf ). I hope that makes the article overall more internally consistent, rather than seeming to have individual sections disagreeing with each other. 04:38, 16 May 2016 (UTC)~ - an occasional anonymous contributor, mostly of spelling and grammar corrections, but I do an occasional more ambitious repair when I see one I can manage... — Preceding unsigned comment added by 173.180.149.245 (talk)

New Scientific Results (Nature journal) paper indicates an Ice Age triggered by the Siberian Traps may be a cause

A new paper in the Nature open access journal Scientific Reports from researchers at University of Geneva and University of Zurich, based on examination of stratigraphy from the Nanpanjiang basin in southern China, indicate the Siberian Traps event caused a short, deep Ice Age that caused various aspects of the extinction. This was followed by a run-away greenhouse event that extended the length of time the extinctions lasted. This needs to be folded into this article if it holds up.

Björn Baresel, Hugo Bucher, Borhan Bagherpour, Morgane Brosse, Kuang Guodun, Urs Schaltegger. Timing of global regression and microbial bloom linked with the Permian-Triassic boundary mass extinction: implications for driving mechanisms. Scientific Reports, 2017; 7: 43630 DOI: 10.1038/srep43630

Redwolfe (talk) 14:25, 31 March 2017 (UTC)

Further reading of the paper reveals to me that the main focus of the article is actually on Pb/U zircon time studies to refine the width of the PTBME horizon, and the Ice Age hypothesis is a small part of the discussion. The popularity of the Ice Age factor is due to media interests.

Redwolfe (talk) 14:55, 31 March 2017 (UTC)

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"Encounter with spiral arm"

This strikes me as an entirely implausible explanation from a non-expert that falls into the category of fringe theory. Do we really need to include it here? --Kent G. Budge (talk) 18:40, 20 February 2020 (UTC)

Imaginative but implausible. Keep it in social media, not here. I'd agree to delete it. --Catrachos (talk) 10:48, 21 October 2020 (UTC)

The source is John Gribbin, a PhD in astrophysics and a respected science writer. The suggestion may be dated in the light of recent evidence, but it is not fringe. Dudley Miles (talk) 11:01, 21 October 2020 (UTC)

I'm a PhD in astronomy. I find the proposed mechanism (dimming of the sun by interstellar dust) implausible in so many ways it isn't even funny. --Kent G. Budge (talk) 06:20, 5 December 2020 (UTC)

Wikipedia does not work on what editors find plausible but on citing reliable sources. If you can find one that contradicts Gribbin, then add it to the article. Dudley Miles (talk) 12:09, 5 December 2020 (UTC)

I would take it out, unless other qualified researches support it as a possibility, otherwise its undue weight for one mans speculation (it could go onto his own article) - with little traction in the scientific community. Hardyplants (talk) 12:24, 5 December 2020 (UTC)

It has been discussed by qualified researchers. Searching on "spiral arm Permian–Triassic extinction" in Google Scholar lists articles including [1] and [2]. Dudley Miles (talk) 15:20, 5 December 2020 (UTC)

I actually did google "spiral arm" "mass extinction". The articles it dredged up seem to focus on supernovae as the trigger for mass extinctions. That has its own problems (I'd love to have a good statistician debunk the purported correlation) but it's not the mechanism attributed to John Gribbin in the article. The notion that interstellar dust dims the Sun and caused the P-Tr extinction is frankly risible. It's presented as an aside in a book on a different subject (to which, oddly enough, I am somewhat sympathetic: the rare-Earth hypothesis) which has not undergone peer review. If it's not been debunked, it's because, as a non-peer-reviewed speculation in a popular book, it's not worth anyone's time.

I could do such a debunking, but if it's done here, it will be doubtless be flagged as WP:OR. I'd begin with the problem of getting dust particles past the heliopause, and point out that dust from comets, which is very similar to interstellar dust, is obviously and visibly swept out of the inner solar system by the solar wind as the comet's tail. And I'd probably add that even if it was not, the optical depth of dust in all but accretionary cores of large molecular clouds is trivial over an astronomical unit, and the odds of the solar system passing that close to an accretionary core are miniscule. I could further point out that the effect of solar dimming is to lower global temperatures, but the P-Tr extinction was characterized by a sharp rise in global temperatures. But, as I said, I'd not do that debunking here, since it would be flagged as WP:OR.

Hardyplants is right: Unless you can find an article that gives traction to this particular mechanism (e.g. solar dimming by spiral arm dust) then it's an un-peer-reviewed speculation in a popular book that simply lacks the notability to be here. --Kent G. Budge (talk) 16:21, 5 December 2020 (UTC)

Just to be clear: My argument against this paragraph is lack of notability. The debunking I didn't do was just to highlight why this is not notable: It was never peer-reviewed and has gained no traction. Had it been competently peer-reviewed, it would never have seen the light of day.

That said: There is, as you note, a body of peer-reviewed articles suggesting a correlation between spiral arm crossings and mass extinctions. Leaving aside that they are not specifically about this mass extinction, and so should probably be discussed in that article rather than here: The mechanisms suggested (enhanced cosmic ray rates, increased impactor rates, nearby supernovae) have their own problems, but may at least pass the laugh test. I would support a paragraph on this hypothesis in the mass extinctions article (if there isn't one already -- I haven't checked) but would insist including this, which does the statistical analysis right and finds the correlation spurious. Or, better yet, this review, where you don't have to wade through a poor English translation. --Kent G. Budge (talk) 17:26, 5 December 2020 (UTC)

The articles I cited do link this extinction, among others, with spiral arms in their abstract, but I do not have access to the full papers for the mechanisms they are discussing. If none of them discuss his mechanism, then I am happy for it to be deleted and replaced by discussion of mechanisms which do have support. I do however have doubts about both the refutations you link. The first appears to be version 1 of an article not yet published, and therefore may not be the peer reviewed version. The second is a review article in 2009 and cannot be a refutation of later articles such as [3].

I took the liberty of removing it. John Gribbin doesn't have any meaningful credentials on this topic, why bother including such an outlandish claim? It doesn't contribute anything to the article and only serves to mislead. If someone can come up with a more reliable source than this goofball's book, I'd personally have no qualms about it being reintroduced. Not that anyone cares. 2603:9000:DE09:75FB:C061:FF04:6688:80E0 (talk) 23:41, 3 April 2021 (UTC)

I see this has come up again. I continue to believe this paragraph should go. The author is not a subject area expert, the specific mechanism being suggested is wildly improbable, and this really qualifies as fringe. This is not the same mechanism being proposed in peer-reviewed papers claiming a connection between the Sun's galactic orbit and mass extinctions -- papers that themselves have been severely criticized, e.g., [[4]] --Kent G. Budge (talk) 16:06, 4 April 2021 (UTC)

Recent Developments - Driver of the largest mass extinction in the history of the Earth identified

Following articles may be both interesting and useful:

• Permian–Triassic mass extinction pulses driven by major marine carbon cycle perturbations
• (Review) Driver of the largest mass extinction in the history of the Earth identified

--Catrachos (talk) 10:43, 21 October 2020 (UTC)

91% species mortality reduced to 86%

A recent edit, sourced to a 2016 paper, lowers the species mortality percentage. As I don't do much reading of papers in this area, would someone familiar with this field please evaluate whether the cited source is reliable, applicable and secondary?--Quisqualis (talk) 19:11, 17 December 2020 (UTC)

The paper estimates that 81% of marine species disappeared. I do not see any reference to 86%. Dudley Miles (talk) 22:22, 17 December 2020 (UTC)

Stanley contends that the 91% is derived from inappropriately conflating the end-Permian extinction with previous Late Permian extinction events. Hemiauchenia (talk) 22:53, 17 December 2020 (UTC)

Missing relevant theory

There are several studies that point out that probably a major astronomic, such as a supernova, passing stellar object or any fast ray object pointed at us, such as a fast spinning neutron star, galactic core. Eduemoni^↑talk↓ 13:32, 10 February 2021 (UTC)

Because they are all harebrained theories with no substance. Maybe they'd be worth noting in a section labelled "Fringe theories" but they're not worth giving any weight to. Hemiauchenia (talk) 14:41, 18 April 2021 (UTC)

The lead

The lead currently states that

There is evidence for one to three distinct pulses, or phases, of extinction. Potential causes for those pulses include one or more large meteor impact events, massive volcanic eruptions (such as the Siberian Traps), and climate change brought on by large releases of underwater methane, methane-producing microbes, or combustion of fossil fuels.

I think that as written this is poorly worded and outdated. From reading the recent literature, the consensus seems to be that the eruption of the Siberian Traps and the associated massive release of carbon dioxide causing elevated temperatures and oceanic anoxia is the primary cause of the extinction. The clathrate gun and the combustion of fossil fuels are directly linked to volcanism in the literature, so to present them separately is misleading. The claims of various meteor impact craters don't seem to be taken seriouisly outside the papers that propose them. Hemiauchenia (talk) 14:56, 18 April 2021 (UTC)

I agree. There is impressive evidence supporting a single massive extinction triggered by the Siberian Traps superplume. Be bold. --Kent G. Budge (talk) 18:33, 18 April 2021 (UTC)

Done. Hemiauchenia (talk) 13:07, 19 April 2021 (UTC)

References

Regconition?

I know adding featured article is vandalism but think about it, but think about it for that The Great Dying is the worst extinction event so far an event in the entire prehistory of earth. Articles big and well known like this should have featured articles. Will anyone volunteer to nominate the Permian Triassic Extinction Event article for the featured article. Will someone, please? talk

You should understand that featured article status is not based on the importance of the article's subject. It's based on whether the article does an outstanding job of presenting the subject. Take a look at Wikipedia:Featured articles.

Before this article is nominated for a featured article, it will need to be brought up to featured article quality. I agree that the topic is important enough that it's worth making the effort. But you're not just asking someone to nominate the article; you're asking someone to put in quite a lot of work to really put the polish on the article. --Kent G. Budge (talk) 03:49, 26 April 2021 (UTC)

I think you are confusing the topic of Wikipedia:Vital articles, which denotes significant topics, with WP:Featured articles, which are about article quality. This article is nowhere near FA quality, not by a long shot. Hemiauchenia (talk) 09:46, 26 April 2021 (UTC)

All is good except for the article polishing, can someone please list me something to improve the article for nomination? talk

sign your posts with four tildas (~) before posting - thanks104.169.18.254 (talk) 07:05, 5 May 2021 (UTC)

See Cretaceous–Paleogene extinction event for a featured article. This should give you an idea of what is needed. You would need to register as an editor. Good luck with your editing. Dudley Miles (talk) 09:47, 5 May 2021 (UTC)

Thanks, but will you help me.

Edit war

Pgan002 is edit warring to include the following wording: It has also been proposed that the burning of fossil deposits by the Siberian Traps ... contributed to the extinction. To a layman, this section is confusing, what does "burning of fossil deposits" mean? "burning of fossil fuel deposits" is a much clearer wording IMO. Hemiauchenia (talk) 00:25, 6 May 2021 (UTC)

I've changed it to coal per Field evidence for coal combustion links the 252 Ma Siberian Traps with global carbon disruption. Hemiauchenia (talk) 00:29, 6 May 2021 (UTC)

Reluctant to stir the pot, but this is fascinating: According to McGhee, the Tunguska Basin includes Neoproterozoic strata containing the oldest petroleum deposits in the world. The interaction of the Traps magmas with these deposits generated much of the gas that blew out the hundreds of blast pipes in the area. Precambrian petroleum! Mother Nature was really pitching a fit. --Kent G. Budge (talk) 04:13, 6 May 2021 (UTC)

I changed it to "oil, coal and hydrocarbons" based on the source before seeing this thread, but if anyone has a better wording then change it again. Dudley Miles (talk) 12:34, 6 May 2021 (UTC)

Carbon dioxide levels

What were the carbon dioxide levels (in parts per million) during this period? Why is this basic information not already included in the current version of this article? 173.88.246.138 (talk) 23:48, 21 May 2021 (UTC)

The levels are poorly constrained, but I've added rough estimates based on a review article on the event.--Kent G. Budge (talk) 01:05, 22 May 2021 (UTC)

Bolide section removal

I think there is a consensus among scientists that a bolide impact event is unlikely to be a relevant cause of the Permo-Triassic extinction. However I am not sure the claims should be totally omitted from the article. The section that Dudley Miles removed was outdated and arguably gave too much weight to the impact claims, but the bolide impact theories have played a significant role in the historiography of the Permo-Triassic extinction, for instance the 2001 paper in Science entitled Impact Event at the Permian-Triassic Boundary: Evidence from Extraterrestrial Noble Gases in Fullerenes has been cited over 500 times. Hemiauchenia (talk) 21:59, 10 June 2021 (UTC)

I tend to agree. The section was much too long for a theory no longer widely considered viable. But to the extent the idea prompted fruitful new lines of inquiry, it ought to be mentioned briefly, along with some well-sourced explanation of why it is no longer considered viable by most geoscientists. --Kent G. Budge (talk) 22:07, 10 June 2021 (UTC)

I am happy for the section to be restored in a shortened form with a sourced statement that the theory is no longer taken seriously by mainstream experts. Dudley Miles (talk) 08:58, 11 June 2021 (UTC)