Talk:Supervolcano/Archive 1
This is an archive of past discussions about Supervolcano. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
Archive 1 |
Armageddon
So there's this link in the ext link section
which I'm going to remove. I thought I should be extremely specific about why. The linked article is a short intro to Super Volcanos as an engine of Armeggedon. This makes sense because it's on an Armeggedon website, where a brief and deliberately menacing article makes sense. But the text is not useful in the Encyclopedic sense of being useful to someone who wants to know the generally accepted understanding of what is a supervolcano is in the context of Geology. As an example, the linked article's description of what is a supervolcano provides such a broad definition that it fits pretty much every volcano in the Cascade Range. -- Cjensen 00:12, 16 Oct 2004 (UTC)
- I do not dispute the removal of this link. - Gilgamesh 03:48, 16 Oct 2004 (UTC)
The Supervolcano dramadoc probably needs a separate article fleshing out the cast and plot a bit. Lee M 00:53, 24 Mar 2005 (UTC)
I agree with the author
That it is better suited to be listed on a armegeddon site for that topic, but in an encyclopedia I agree that it is more like and apart of the cascade ridge and should be listed here for that purpose. Armageddon could use links to this as maybe a future concern. That would include some other possible places. The conclusive proof that this will happen here again and the outcome from it is nonconclusive. So I agree with the author removing that article for this listing. I agree.
- Note: indenting paragraphs causes them to become boxed and unwrapped, causing lots of horizontal scrolling, as in this case (now fixed). Please avoid! And please sign posts if you're a member! Lee M 01:09, 25 Mar 2005 (UTC)
Eruptions
"VEI-8 eruptions are not so great as to form mountains, but instead circular calderas, resulting from the downward collapse of land at the eruption site to fill emptied space in the magma chamber beneath." I'm not happy about this statement at all. It implies that if the eruption were somehow 'greater' they would form mountains. You don't get much 'greater' than a class of volcanic eruption STARTING at 1000km3 of ejecta. Mountains are formed through entirely different geological processes to these volcanos which leave large calderas. Even if the author were thinking of a volcanic cone or stratovolcano the 'greatness' of the eruption has nothing to do with it.
Could use votes to save this article, thanks MapleTree 22:39, 28 September 2006 (UTC)
Supervolcano's gonna blow, kook theory or what?
http://www.crawford2000.co.uk/yellblow.htm I came here to fact check the link above. Given that it's on a kook conspiracy site, I'm assuming that it's all Art Bell stuff. Yellowstone is geologically active, fact. They've had to close some areas because of increased geologic activity, fact. Yellowstone is also overdue for an eruption in a geologic timeframe, fact. But in geologic time, anything from now to 50,000 years off is "soon." Should there be a section addressing this sort of thing? Gmuir 12:49, 14 May 2007 (UTC)
Supervolcano under Czech Republic?
Some weeks ago I watched a documentation on German TV in which they said that a supervolcano was under the Czech Republic. Does anyone know whether this is true or not?
- Not, in terms of anything presently active. It is certainly possible that some major volcanic center was there at some time in the geologic past; they may have been referring to the Doupov Volcanic Complex which I believe is Eocene to Oligocene in age. But, I'm pretty sure there is no modern Yellowstone equivalent sitting under the Czech Republic waiting to blow; sleep comfortably. Cheers Geologyguy 14:22, 23 May 2007 (UTC)
Verneshot?
Verneshot? 70.51.9.197 05:23, 13 August 2007 (UTC)
Toba vs Yellowstone
This is something I have seen on the web quite a bit now. There seems to be some confusion over which is a larger volcano, Toba or Yellowstone. If we were going off eruptions then really there's only one winner to my knowledge and that is Toba,however, if we were to go off magma chamber size then I have no idea which is bigger as I don't know the size and capacity (in Cubic Km) of Toba's Chamber. Does anybody have any knowledge on the size of the magma chamber beneath Toba ?. Wiki235 19:42, 13 October 2007 (UTC)
Supervolcano locations
Nova, some unlisted here. JAF1970 18:12, 11 November 2007 (UTC)
- Most listed there don't fall into the 1000km3 plus category. --LiamE 10:19, 12 November 2007 (UTC)
Actually seeing as 240 cubic miles is 1000 cubic km then most of them do fit into the VEI 8 category.Wiki235 (talk) 22:24, 17 November 2007 (UTC)
- My mistake. I had misread the units. --LiamE (talk) 09:31, 29 November 2007 (UTC)
I think Siberian super volcano should be mentioned too.
This a link on Discovery channel: [1]
- The article says "For large igneous province eruptions, see that article.". Supervolcano is a poorly defined term. -- Cjensen 22:18, 12 September 2006 (UTC)
The volcano you refer to isn't actually a volcano - more a massive basaltic province - the Siberian Traps. Basalt is non-explosive, able to flow hundreds of km under the right conditions. What the Siberian Traps did was to load the atmosphere with CO2 and other noxious gases, pour huge volumes of molten lava onto the surface and is considered to have impacted upon the end of the Permian extinction.
Super eruptions which you are mixing up occur at explosive volcanoes because the magma is silicic rich. A simple experiment you and any teacher can do is to get several glasses and fill them with water, next get two or three bags of sugar. One glass leave alone, now add sugar into the glasses and stir the mixture.
It will become sweet and sticky, fill one glass with sugar until you cannot put anymore in - it will be so sticky that you cannot do much with it. Leave them covered for a few days away from any heat. Now slowly pour the glass with water on to a table and watch how far and easy the water flows, do the same with each glass in turn and you will find that as the sugar content increases the saturated liquid will flow less distances until you come to the glass that is full of wet sugar. Pour it out - and not how far it flows.
The glass that is almost entirely full of wet sugar is like the magma of a "super-volcano" and it has other properties too. Get a drinking straw and try and blow through the water only then through each of the glasses with sugar in them. It becomes more difficult to get the bubbles you have blown into the sugar to pass through - gas retention is the reason why magma explodes. The water only can be likened to basalt whilstthe almost 100% sugar can be likened to the magma in a super eruption. Sticky or viscous, holds great volumes of gas and therefore is able to be pressurised to the point of explosion.
Large Igneous Provinces therefore by definition are not so called "super volcanoes." The Geologist (talk) 12:53, 5 March 2008 (UTC)The Geologist
Please cite the source for verification....
Though there is no well-defined minimum explosive size for a "supervolcano", there are at least two types of volcanic eruption that have been identified as supervolcanoes: massive eruptions and large igneous provinces.
...if there are any. Thanks!
Zxyggrhyn (talk) 00:21, 18 February 2008 (UTC)
This sentence seems to have been damaged in the article... it currently reads "There are at least two types of volcanic eruption that have been identified as supervolcanoes: massive eruptions." (period) —Preceding unsigned comment added by 75.85.35.164 (talk) 08:34, 16 May 2008 (UTC)
Historic Times
The article notes that two eruptions have occurred in historic times -- but the definition of "historic times" seems to be at issue. Historic times can simply be defined as the time in written accounts, observations or other records are available for review. However, historians also acknowledge that oral records and accounts, sometimes considered prehistoric, can have value as historic records. See History article and definition below.
- The line of demarcation between prehistoric and historical times is crossed when people cease to live only in the present, and become consciously interested both in their past and in their future. History begins with the handing down of tradition; and tradition means the carrying of the habits and lessons of the past into the future. Records of the past begin to be kept for the benefit of future generations.(Carr, Edward H. (1961). What is History?, p.108, ISBN 0140206523)
Clearly, in the case of the contested New Zealand eruption, we have no local accounts. But there are records -- written records -- of atmospheric phenomena consistent with the eruption within the CE in both China and Rome -- historic time in well recognized historic areas. These records have been recently used to help date this historic eruption -- written/historic records documenting a historic event. I provided both a written source and a ex. link which summarized that source, as requested, and was again reverted. I have attempted to restore that material for other editor's review and discussion. But Black Tusk seems to think protecting a page is a way to win an argument. As a responsible editor, I find that insulting. Please release the page and do not revert yet again. Just me! (talk) 01:12, 4 July 2008 (UTC)
- I asked you to find a simple reference that indicates the eruption as historic. If you look through the history you will see I reverted by last edit because you added a reference, and thus I agree now. And I wasn't trying to protect the page by the way. --Black Tusk (talk) 01:55, 4 July 2008 (UTC)
- Thank you. Just me! (talk) 02:14, 4 July 2008 (UTC)
- You should have looked before you posted this discussion. --Black Tusk (talk) 17:57, 4 July 2008 (UTC)
- Thank you. Just me! (talk) 02:14, 4 July 2008 (UTC)
- While we're "shoulding" -- you "should have" posted something other than revert AGAIN and revert! Just me! (talk) 21:31, 4 July 2008 (UTC)
- Please kindly review WP:Civility. It is not really appropiate to dismiss the views of other editors by advising them they do not know the facts. Thus that's something a responsible editor wouldn't do. I have been a longer member of Wikipedia then you have and I "did" post something other than revert AGAIN and revert, I posted: find a reference. Take it easy, for chrissake, and don't get paranoiac. --Black Tusk (talk) 01:53, 5 July 2008 (UTC)
- While we're "shoulding" -- you "should have" posted something other than revert AGAIN and revert! Just me! (talk) 21:31, 4 July 2008 (UTC)
VEI-7
According to the current state of this article, anything VEI-7 or bigger is considered supervolcanic. Is this correct? Should I add Category:VEI-7 volcanoes to Category:Supervolcanoes? I'll do that. - Gilgamesh (talk) 23:05, 30 November 2008 (UTC)
Diagram
It is requested that a geological diagram or diagrams be included in this article to improve its quality. Specific illustrations, plots or diagrams can be requested at the Graphic Lab. For more information, refer to discussion on this page and/or the listing at Wikipedia:Requested images. |
It would be helpful to visualize the subject to have a diagram showing a caldera and other elements of a supervolcano structure. -- Beland (talk) 00:28, 5 January 2009 (UTC)
- I've added a cross-section of Long Valley Caldera. -- Avenue (talk)
Under water super volcanos?
Since 3/4 of the planet is covered by oceans, shouldn't there be super volcanos under the oceans? Is there any information about this? --Serge 18:05, 27 September 2006 (UTC)
- Most submarine volcanos are located away from continental crust, so the chemical composition is different and the lava tends to be basalt which is not prone to explosive eruption like Stratovolcanos are. So the best a hot spot can do is create an island like Hawaii. -- Cjensen 23:19, 29 September 2006 (UTC)
- The pressure underwater only allows effusive eruptions. Guanlongwucaii (talk) 11:53, 31 May 2009 (UTC)Guanlongwucaii
- If you said "deep underwater" I might agree, but your comment seems wrong as it stands. See e.g. Spatiotemporal evolution of a marine caldera-forming eruption ... -- Avenue (talk) 12:37, 31 May 2009 (UTC)
Heh, I was just about to mention Kikai Caldera, but that link already did.
Oops, I didn't specify the depth. Yes, it is supposed to be DEEP. Thanks! Guanlong wucaii 13:44, 3 July 2009 (UTC)Guanlongwucaii
'Media portrayal'
"Millennial Ice Age that lasted for ~1000 years", is this name ok? I'd like to get a citation. "The Wisconsin Glacial Episode has three glacial maxima separated by interglacial warm periods. These glacial maxima are called, from oldest to youngest, Tahoe, Tenaya and Tioga". Nothing like a millenium, but more than 10,000 years. --Chris.urs-o (talk) 20:50, 7 February 2010 (UTC)
'Millions of times'
This is incorrect. Supervolcanic eruptions are all VEI-8. There have been VEI-7 eruptions during historical times e.g. Tambora, Taupo etc. A VEI-8 eruption erupts 10 times more material than a VEI-7. Therefore, this statement is an exaggeration and should be removed. --Guanlong wucaii 14:30, 7 February 2010 (UTC)
- Seems ok for me. It can be done, if nobody disagrees. --Chris.urs-o (talk) 18:59, 7 February 2010 (UTC)
- I agree it's incorrect. I'll tone it down. -- Avenue (talk) 22:27, 7 February 2010 (UTC)
What about Kamchatka?
I thought that the Valley of Geysers in Kamchatka, Russia, was also a supervolcano caldera -- is it not? I am pretty sure it was mentioned either in the Discovery channel program or one of the USGS pages, don't remember for sure now... 71.137.232.116 (talk) 08:39, 13 October 2009 (UTC)
- There are many calderas in Kamchatka. "The twin Uzon and Geysernaya calderas, containing Kamchatka's largest geothermal area, form a 7 x 18 km depression that originated during multiple eruptions during the mid-Pleistocene. Widespread ignimbrite deposits associated with caldera formation have a volume of 20-25 cu km (exclusive of airfall deposits)".(http://www.volcano.si.edu/world/largeeruptions.cfm) The Kikhpinych volcano is in the same region. I did not find a VEI 8 event. --Chris.urs-o (talk) 21:33, 7 February 2010 (UTC)
- And by the way, the Valley of Geysers is not a volcano - it's just a volcanic feature. Check out the page on geysers.--Guanlong wucaii 15:38, 13 February 2010 (UTC)
Africa
In the following link http://www.pbs.org/wgbh/nova/megavolcano/blas-flash.html, they state that there was an eruption in Yemen 29.5 mya, which produced ~1,600 cu mi (6,700 km3) of ignimbrite, apparently known as the Sam Ignimbrite. Could someone find more references for this eruption, because if the figures are true, this eruption DWARFS the La Garita Eruption.--Guanlong wucaii 15:48, 13 February 2010 (UTC)
- http://www.largeigneousprovinces.org/Downloads/Ukstins.pdf a PDF which talks about it, but it says up to 2,000 km3 (480 cu mi) which means that it wasn't bigger than La Garita, although it's still huge. Perhaps the figure on pbs.org was inaccurate...--Guanlong wucaii 15:54, 13 February 2010 (UTC)
- I only found the flood basalt Affinities, Ethiopia/Afar/Yemen, 28.5 Ma, more than 350,000 cubic km. Table S1: Major volcanic eruptions and provinces. --Chris.urs-o (talk) 14:39, 16 March 2010 (UTC)
- Table 4: Summary of estimated eruption volumes for main silicic pyroclastic units, Oligocene flood volcanism, Yemen in this paper, doi:10.1007/s00445-005-0428-4, could be interesting. I don't have access to the full paper, but one of the related snippets on the publisher's website reads: "This yields minimum volumes of 3,700 and 5,550 km 3 for distal tuffs associated with the Jabal Kura’a and Sam Ignimbrites, respectively". I'll add it to the article using that minimum volume for now. -- Avenue (talk) 09:19, 17 March 2010 (UTC)
Bruneau-Jarbidge event
At present, the Bruneau-Jarbidge eruption is listed on this page as a VEI-8 volcanic event. It was brought to my attention that it wasn't listed in any publications as an event of that size. From the Bulletin of Volcanology, I found this:
“ | Equally, the long-lived Yellowstone-Snake River Plain "hotspot" province (Smith and Braile 1994) has an extensive ash-fall tuff record suggesting that it has experienced many tens of eruptions with volumes in excess of 250 km³ over the past 16 Ma (Perkins and Nash 2001). Volumes of associated major ash-flow tuffs have, however, only been determined for deposits of the past 8 Ma (Morgan et al. 1984; Christiansen 2001). It is likely that several large volume eruptions associated with the earlier stages of the province, between 16 and 10 Ma, remain to be identified. | ” |
Is there any other information out there about these older eruptions? – Swid (talk | edits) 18:31, 9 August 2006 (UTC)
- Smith, Robert B. et.al. (2009) cites Perkins, Michael E.; Nash, Barbara P. (March 2002). "Explosive silicic volcanism of the Yellowstone hotspot: the ash fall tuff record". The Geological Society of America Bulletin. 114 (3): 367–381. doi:10.1130/0016-7606(2002)114<0367:ESVOTY>2.0.CO;2. for the older eruptions, and Christiansen, R.L. (2001). "The Quaternary and Pliocene Yellowstone Plateau volcanic field of Wyoming, Idaho, and Montana". U. S. Geol. Surv. Prof. Pap. 729-G. Denver, CO: U. S. Geological Survey: 120. for the more recent minor vents. --Chris.urs-o (talk) 03:17, 1 July 2010 (UTC)
Supervolcano vs super eruption
This article treats the term "supervolcano" for calderas that have produced "super eruptions". I personally disagree with this because like the article states, it is a blanket term that can be applied to a number of different geological conditions. There probably are supervolcanoes that never had super eruptions. For example, I have never seen anything about the Blake River Megacaldera Complex producing a massive explosive eruption like Yellowstone or Toba, although I have read that Yellowstone has a giant magma chamber probably of the same order to the Blake River Megacaldera Complex. I would change the article defination myself but I don't know much about supervolcanoes. Volcanoguy 21:57, 6 October 2012 (UTC)
- Also worthy to note is that volcanic calderas can be formed by two different processes: overpressure of an underlying magma chamber, followed by major explosive activity and underpressure of an underlying magma chamber, followed by effusive activity. Volcanoguy 22:29, 6 October 2012 (UTC)
Goofy use of 'asrtrobleme'
'....The scientific consensus is that an astrobleme impact was the cause of the extinction event,....' . This wording, found in the section on 'Large Igneous Provinces', is goofy in that it is an improper use of an outdated word. . 'Astrobleme' isn't commonly used today, but when it was in use, the meaning was roughly, 'weathered impact crater'. . Replacing the word with the definition for the sentence in question reveals the problem with this construction: 'The scientific consensus is that an weathered impact crater impact was the cause of the extinction event'.... . Hopefully that makes it clear. . To make sure I am not alone in my analysis, I am going to rely on someone else who understands the problem to edit the article. . Thank you 70.185.124.103 (talk) 23:36, 19 December 2012 (UTC)BGriffin
- I've changed it to 'meteorite impact', which makes a lot more sense. Thanks for pointing that out. Mikenorton (talk) 23:43, 19 December 2012 (UTC)
1cm of ash?
I looked this up after my science teacher was discussing the subject with us today, and he said it was more likely to be 1m of ash covering North America, not 1cm. I'm not sure if this is accurate or not but he is the sort of person who knows what he's talking about. Antoher thing to add is that the volume of ash would be so great it would probably plunge the rest of the world into around 2 months of darkness. Can anyone verify this?
- "Even the US East Coast could be paralysed by 1cm of ash", according to the BBC website pages accompanying the programme. (I do find that a surprisingly low figure, though, given that according to the Lake Toba article, "although the (Toba) eruption took place in Indonesia, it deposited an ash layer approximately 15 cm (6 in) thick over the entire Indian subcontinent.") Vilĉjo 13:20, 13 May 2006 (UTC)
If the eruption was a full scale one it would certainly bury vast areas around the eruption site with ash and lava hundereds of feet thick and most definitely cover a vast area of the United States with ash depths of about 1cm or more. Also if the eruption was large enough and enough sulfur was emitted into the atmopshere (say 2000-4000 megatons) then it could repeat the Lake Toba incident and create a millenium of freezing.
- As to the thickness, the largest Yellowstone eruptions did not cover all of North America with ash - the most distant confirmed ash from Yellowstone is, I believe, in the state of Mississippi where it is something less than an inch (<2 cm) thick. This is not to say that it would not have caused a problem all over the continent; it very likely would have. Geologyguy 15:29, 28 January 2007 (UTC)
1 inch is equal to 2.54 cm. 1 cm is equal to 0.4 inches.The Geologist (talk) 15:42, 23 January 2013 (UTC)
The 1 cm of ash quoted is NOT what the projected super eruption at Yellowstone is expected to deposit. 1 cm of ash will cause power cables to snap, electrical switchgear to short out and cause massive disruption to water supplies, electricity, aviation and many other things we take for granted. The projected Yellowstone super eruption will deposit ash and pyroclastics several tens of metres - and possibly hundreds of metres thick close to the site of the eruption, at several hundreds of km the thickness will still be measurable in metres or maybe tens of metres. When Mount St Helens exploded in a VEI 5 in May 1980, it deposited almost 15 m of ash and pyrclastics at the limits of the pyroclastic surges. I know because I was not only there that day but have done a lot of work with the USGS in respect of MSH. The Geologist (talk) 12:39, 5 March 2008 (UTC)The Geologist
Glen Coe
Glen Coe, Scotland should be listed under VEI 8. I'm not a Wiki expert so I'm not going to mess around with the page, but could someone who knows what they're doing add it? —Preceding unsigned comment added by 92.11.23.130 (talk) 13:32, 11 September 2010 (UTC)
- Do you have a source we can cite? I've looked through the online ones cited in our Glen Coe article with no luck. The caldera size (8x16 km, [2]) seems on the small side for a VEI-8 eruption. --Avenue (talk) 22:24, 11 September 2010 (UTC)
- Quote from Glen Coe article: "Geologically-speaking, Glen Coe is the remains of an ancient supervolcano that erupted with a force of VEI-8." (Last paragraph in the 'Geography' section.) —Preceding unsigned comment added by 92.1.250.169 (talk) 20:15, 13 September 2010 (UTC)
- We cannot cite other Wikipedia articles as sources, or we just end up chasing our tail (see WP:CIRCULAR). I did check the sources cited in that paragraph of our Glen Coe article, but neither supports the VEI-8 claim. I've added a tag requesting a source there; if no one obliges, that claim should be removed. --Avenue (talk) 22:07, 13 September 2010 (UTC)
- This says both Glen Coe and Scafell are ancient supervolcanoes but does not specifically say they were VEI8. Same with this. Someone with access to Kokelaar, B. P and Moore, I. D; 2006 Glencoe caldera volcano, Scotland British Geological Survey ISBN 0852725256 or even Clough, C. T; Maufe, H. B. & Bailey, E. B; 1909. The cauldron subsidence of Glen Coe, and the Associated Igneous Phenomena. Quart. Journ. Geol. Soc. 65, 611-678 might be able shed light on the estimated size of the eruption. --LiamE (talk) 17:34, 14 September 2010 (UTC)
- Google scholar helps. "The Cauldron-Subsidence of Glen Coe, and the Associated Igneous Phenomena". Quarterly Journal of the Geological Society, London. 65 (1–4): 611–678. 1909. doi:10.1144/GSL.JGS.1909.065.01-04.35.
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ignored (help) "Timing, relations and cause of plutonic and volcanic activity of the Siluro-Devonian post-collision magmatic episode in the Grampian Terrane, Scotland" (PDF). Journal of the Geological Society, London. 166 (3): 545–561. 2009. doi:10.1144/0016-76492008-069.{{cite journal}}
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ignored (help) --Chris.urs-o (talk) 18:44, 14 September 2010 (UTC)
- Skimming through the Neilson, Kokelaar & Crowley paper, I don't see any confirmation that Glen Coe produced a VEI 8 eruption. It does say that "thousands of km3 ... were erupted repeatedly" over 22 million years from several eruptive centres in the southern Grampians region, but that doesn't narrow things down much. They do discuss one post-caldera eruption of at least 12 km³ within the Glencoe Volcanic Formation, but that seems to be the only volume they give for an eruption (as opposed to an entire volcano or lava pile). --Avenue (talk) 16:06, 15 September 2010 (UTC)
- I have to agree at least in part. The article certainly does not conclude or specifically state that there was a single eruption of 1000km3 at Glen Coe but on the other hand trying to exstimate the sizes of the eruptions 400 million years after the fact in a heavily uplifted and eroded area is no mean feat. On the other hand the evidence for existence of extreme vulcanology involving many 1000's of cubic kilometres of material over a period is extensive. Based on that I cant be sure from what I have read that there were any VEI8 erruptions in the area but the area does qualify for the supervolcano tag as at the very least it had multiple high end VEI7 eruptions. --LiamE (talk) 19:06, 15 September 2010 (UTC)
- Yes, I agree we can and should say Glen Coe was a supervolcano; we have sources that say as much. I wouldn't be surprised if it did produce a VEI 8 eruption, nor would I be too surprised if someone establishes this someday. My point is that until someone does publish this finding (or we can confirm that someone already has), we should not make this claim ourselves. --Avenue (talk) 21:16, 15 September 2010 (UTC)
- I was looking at our list of largest volcanic eruptions, and I think there's only one VEI-8 eruption more than 40 million years old for which the eruptive centre has been identified. So confirming this for Glen Coe would be quite a feat. --Avenue (talk) 00:57, 16 September 2010 (UTC)
On Wednesday 23rd January 2013 I personally contacted Professor Peter Kokelaar, who is the recognised expert on Glen Coe geology. This is verbatim his reply: "Depends on definition of s-v (super volcano) but prob not. From scale of subsidence Glen Coe records 10s, perhaps several 10s e.g. 50, no more than 100 km^3 abs max eruptions, some 7 of them producing ignimbrite. Of course outflow not preserved, but area vs depth mod well constrained. So not super, just lovely...." So there you have it, Glen Coe is NOT considered to have been the location of a super volcano.The Geologist (talk) 12:21, 24 January 2013 (UTC)
Terminology
The article currently states that Volcanologists and geologists do not refer to "supervolcanoes" in their scientific work. That may have been true ten years ago, but I don't think that it is any more. A search of usage on GoogleScholar with time gives the following results - 2000-2004 [3] (48) 2005-2008 [4] (265) and 2009-2013 [5] (540). I propose that we reword that section to say "At the time of the Horizon programme, volcanologists and geologists did not refer to "supervolcanoes" in their scientific work, although the term has now entered the scientific literature, despite some opposition." or similar, using this source [6]. Mikenorton (talk) 09:18, 24 February 2013 (UTC)
We still don't use the term scientifically - it is used by some who also like to use the media to scream for funding. A certain professor who likes to over-dramatise scientific facts in his continuing quest for attention, is known to use the term "super" for everything and anything that is considered to be worth publicising as imminent. Yellowstone, Cumbre Vieja, are according to the professor overdue and therefore in imminent danger of occurring. — Preceding unsigned comment added by 90.244.55.211 (talk) 16:03, 11 July 2013 (UTC)
Possible Krakatoa VEI 8 Eruption
I believe the eruption of an equatorial volcano in 535 should be mentioned on the list because of its significance. According to one or two tv shows, including the episode of How the Earth was Made about Krakatoa, which airs on History and H2, have mentioned that ice cores from both the arctic and antarctic contain ash dating back to 535. The other show that may have mentioned it airs on Science. Michealin (talk) 00:07, 16 November 2013 (UTC)
- If this event is accepted by the volcanological community as VEI8, I would expect it to be described in at least one scientific paper. From what I can gather, there is no agreement that 535 was the date of a large eruption at Krakatoa, with 416 being the alternative. I suggest that this event is not listed until there is clearer evidence that the size and date are more widely accepted. Mikenorton (talk) 10:27, 16 November 2013 (UTC)
- Okay. The second show above is the "Can Krakatoa Stop Time?" episode of How the Earth Works. While there's a chance the event was VEI 6 or lower, the odds are it was VEI 7, or --more likely-- 8, because the way it's described on the at least one show comes from a local legend that there used to be a single main island that the eruption split into Java and Sumatra. Michealin (talk) 01:01, 17 November 2013 (UTC)
Terminology Section and OR
The terminology section resembles original research, instead of citing references that describe where and when to use the term "supervolcano", it merely cites instances of the term being used, in order to establish usage. Please use reliable sources that discuss usage of the term supervolcano rather than citing instances of the current usage to produce original research. Geogene (talk) 18:42, 17 December 2013 (UTC)
Toba Catastrophe theory - legit or bogus?
I have to ask for straightforward notes regarding the Toba eruption. Currently, it reads:
"The disputed[10] Toba catastrophe theory (if true, could have eradicated 60% of human population)"
Why the Triple redundancy on skepticism? The theory is described with terms "disputed", "if true", and "could have". If it is such a crackpot theory, it shouldn't be mentioned in the notes at all. If, however, it has any validity then we can do without the redundancies and say:
"The Toba catastrophe theory claims this event exterminated 60% of the human population"
Thats legit and proven , see https://www.youtube.com/watch?v=XS8ipDsee0s. many sientists investigated & verified the source of the Toba Ash.
— Preceding unsigned comment added by 166.76.0.1 (talk) 20:49, 27 October 2014 (UTC)
Uturunku - Armageddon 2015
ALLERT . the https://en.wikipedia.org/wiki/Uturunku are ready to BLOW up on VI7 / VI8 scale last Blowup 271,000 years ago, on VI7 Scale - reported by usgs. — Preceding unsigned comment added by 93.223.137.146 (talk) 21:22, 1 July 2015 (UTC)
Laacher See
Why wasnt laacher see mentioned in the supervolcano list? I think I might add it! — Preceding unsigned comment added by Vulkania (talk • contribs) 19:38, 3 June 2012 (UTC)
well thats an Political desions..: DO NOT make EU curriosly whats Lying below complete western europe. New mesures of the magma chambers saying is 5x bigger the yellowstine - AND overdue. — Preceding unsigned comment added by 93.223.137.146 (talk) 21:24, 1 July 2015 (UTC)
VEI 9
I added a VEI 9 subheading for the La Garita Caldera in Colorado, as well as a "see also" link to the VEI article. Both the article on La Garita Caldera itself, and the table of eruptions in the VEI article contradicted the VEI 8 listing for La Garita Caldera in this Supervolcano article. --Biturica (talk) 19:22, 2 August 2008 (UTC)
to the guy who took off the VEI=9 heading for La Garita Caldera, It was in fact that big. It was in fact, BIGGER. AS far as is known, there was nothing even close to it during the entire Paleozoic or Mesozoic. It's explosive and destructive power was a unique occurance in geological history. Might there have been a bigger explosion during the first four billion years of earth history? Probably, but nothing nearly that big has happened since before the age of the trilobites. Let's give La Garita it's due, eh?Ericl (talk) 16:17, 15 November 2008 (UTC)
- The problem is though it was a VEI8 eruption. The VEI scale is openended so a VEI9 eruption is possible but to be considered VEI9 it would have to be oer 10000km3 in size. The La Garita Caldera Event was half that size. --LiamE (talk) 00:24, 16 November 2008 (UTC)
LiamE: Researchers don't disvovered all ancient eruptions till today. some vulcanos are deep under the ocians..
while past 4,5 Tillien years theer was some what VI9 or VI10 class or so called plannet killer explosions.
On Current time this wuold happen allmost due an extreme week magnetfield that let more neutrienos head-up the earth molten core . as per 2015, the magnetflied are reported weakeing and onway to shift .. witch HEATUP the core more ... more heat creates molten Iron that expand that creates more pressures , as an result we see currently more an more Vulcanes Blowup due to that . Simply liquid metal physics that you can test either with every metal / stone / lava - as more heat as more volume !
But there are another issues this time ; as we - men kind - heatup the globe allrteady past 150 years by 3 °C !! ALL Ice are melting arround the globe. AS an result the cooling the global waterflows are allmost expected to compromisted or fully stopped within next 30-50 years. AS lesser ice as lesser the weigth on the plates and they are LIFTUP ... !! IF There is no more ice , nothing cool the continents from melting-up by global waterflows cooling are gone. IF that happen , then it will be VI9 or bigger again.
VEI 9[edit] The Eruptions at the Paraná and Etendeka traps during the Cretaceous period when taken together are well over 15,000 km³, and may have been a single event that was the largest explosion during the Phanerozoic Eon. — Preceding unsigned comment added by 93.223.137.146 (talk) 21:31, 1 July 2015 (UTC)
The eruption may have produced in excess of 15000 km3 but as it was almost all basaltic it is not a VEI9! It belongs in the section relating to LIP's. I have added a comment explaining why as far as vulcanologists are concerned (I am one), there is no VEI 9 and hope this clarifies the matter for the non-scientific readers. The Geologist (talk) 13:28, 8 August 2015 (UTC)
Phlegraean Fields eruption estimate is ridiculous, most sources state minimum 150 cubic km, no maximum estimate. Saying 500 is misleading.
This edit request to Supervolcano has been answered. Set the |answered= or |ans= parameter to no to reactivate your request. |
99.44.121.23 (talk) 06:09, 28 November 2014 (UTC)
- Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format. — {{U|Technical 13}} (e • t • c) 16:18, 28 November 2014 (UTC)
Phlegraean Fields capacity
If the Phlegraean Fields known also the "Fields off hell" erupts again it will be devostating everything arround 700 KM .. and it will be ONGOING for many WEEKS as bevor. Current mesurements calculaction of the magma chainmber benith the Field of Hell are ~15000qm³ volume . — Preceding unsigned comment added by 93.223.185.209 (talk) 14:53, 3 July 2015 (UTC)
- The 150 cubic km estimate uses DRE (dense rock equivalent), compared to 500 cubic km (bulk volume). Probably a good idea to check that all the quoted numbers are in DRE. Thanks for pointing out this issue. Mikenorton (talk) 23:26, 28 November 2014 (UTC)
- Base on crystal concentration method, the true volume of Campanian Ignimbrite is no more than 33 cubic km(DRE) — Preceding unsigned comment added by Aleral Wei (talk • contribs) 05:31, 22 November 2015 (UTC)
Someone please add Mount Mazama to the VEI 7 list.
The eruption of about 5,700 BC expelled at least 100 cubic km of tephra. — Preceding unsigned comment added by 2602:304:CFB6:2E80:80C:9064:6BA:DB9 (talk) 18:55, 29 March 2016 (UTC)
July 2016 Special Report in Science (AAAS) magazine
A couple of pieces of information, some of which conflict with what the Wikipedia article claims:
Taken from the report on pgs 232-7, of the July 15, 2016 issue of Science by Julia Rosen (a freelance science writer (& not a researcher, afaik)) Title: Thinking the Unthinkable.
1."Every 100,000 years or so, somewhere on Earth, a caldera up to 50 km in diameter collapses and violently expels heaps of accumulated magma."
2. "By geological convention, a supervolcano is one that produces an explosive eruption of more than 450 cubic kilometers of magma..."
3. "Locations that remain active today include Toba, the Yellowstone hot spot in northwestern United States, the Long Valley Caldera in eastern California, the Taupo Volcanic Zone in New Zealand, and several spots in the Andes."
4."None of these danger zones now poses a threat."
5."But in the event of another eruption, everything within a hundred km would be incinerated, and ash would blanket continents. Just a few millimeters of the stuff can kill crops; a meter or more can make the land unusable for decades says Susanna Jenkins, a volcanologist at the University of Bristol..."
5. "Most far-reaching [consequence] of all, however, would be the effects on global climate, which would resemble those of a large asteroid impact. Sulfate aerosols injected into the stratosphere by a supereruption could drop temperatures over much of the Earth by 5°C to 10°C for up to a decade, devastating global agriculture."
The article goes on to talk about the large uncertainties in estimating consequences and the possibilities of predicting an eruption weeks, months or years before a supereruption.174.130.19.69 (talk) 04:24, 26 July 2016 (UTC)
TOBA - Human evolution and 75,000BP event
A cable TV program on the evolution of humans from apes discussed the impact of a volcanic winter 75,000 years ago. At that time, humans were still in Africa and it is specultated that the population dropped to as low as 1000. Fortunately at that time humans had language, and the repositioning of the larynx indicated that they had speech. If the behaviour of modern nomadic tribe in the Kalahari is any guide, travelling bands met up with other bands on a regular basis, and would have discussed matters, leading to quick propogation of the best ideas for dealing with the volcanic winter. Tabletop (talk) 08:29, 31 August 2008 (UTC)
That is known & verified as the Toba VI8 explosion.
- Yes, 75,000 years ago human beings were still in Africa, just as they are today. They were also in south China at least 80,000 years ago. Most of the above is nothing more than speculation not supported by Reliable Sources. 104.169.17.29 (talk) 22:49, 1 March 2017 (UTC)
The discovery channel?
I'm not saying the discovery channel isn't reputable, but I think an encyclopedia article could use a more scholarly source, especially if the source is specifically mentioned in the article. This is sort of on the borderline of what is and isn't acceptable in a Wikipedia article, so perhaps some discussion on the issue is in order. — Preceding unsigned comment added by 174.109.111.223 (talk) 01:20, 9 April 2012 (UTC)
Actually I would go so far as to say, as a whole, the Discovery Channel is not reputable. The channel often presents ideas that aren't accepted by experts in academia, such as shows on cryptozoology, "ancient aliens" and the like. I have no doubt that the information they present on supervolcanos is accurate, but the Discovery Channel is not an appropriate source for a Wikipedia article. — Preceding unsigned comment added by 174.109.111.223 (talk) 01:27, 9 April 2012 (UTC)
Any media involving the general public seeks to enhance the science. It is the only way that they can justify their stupendous budgets, trap the public with mind baffling non-science which sadly the general public think is true. We scientists don't help ourselves - we argue publicly, we don't explain science in everyday language. It is no use saying to the public that the lava will have a shear strength of X or that an earthquake realised X megatonnes of energy if the person you are explaining it to doesn't understand what on earth you are saying. Equally the media don't help, they ask questions and twist the answers, make assumptions and then baffle themselves with their ignorance. An example recently put out on TV was the BBC 2 programme about mega-tsunamis. If you believe the programme La Palma is poised to collapse into the Atlantic. However the facts which the programme didn't explain are that the dimensions of the rupture are exactly the same in 2012 as those recorded in 1940, the section that ruptured is about 2.5 km (about 1.5 miles) long, and that the actual Cumbre Vieja from the Cumbre Nueva to Fuencaliente is about 25 km long. In other words about 1/10 of the CV ruptured in 1949, and therefore the obvious unstated fact is that for it to fail en-masse a lot more needs to rupture. Claims that it has moved are based upon the provable fact that the island is on the African plate, which in turn is moving slowly westward. Whether it will fail en-masse or in smaller sections is unknown but one thing is certain it is not expected to happen in the foreseeable future. Another scaremongering production by the media frightening people.The Geologist (talk) 12:37, 24 January 2013 (UTC)
- It's a case by case basis - they've told some whoppers in their time. 104.169.17.29 (talk) 22:51, 1 March 2017 (UTC)
VEI 8
I have understood that a volcano needed to be capable of erupting with a VEI of 8 or more to be termed a super volcano. — Preceding unsigned comment added by RAYLEIGH22 (talk • contribs) 04:07, 12 May 2017 (UTC)
Where did the term supervolcano come from?
"It was used as far back as 1925 in the travelogue Conquering the World, by Helen Bridgeman." Adding this claim now. Note this needs resolving. CapnZapp (talk) 13:42, 25 September 2019 (UTC)
- This was taken from a "Wired" article, which shows that it was being used to describe a sunset, not a geological feature - I've removed the claim. Mikenorton (talk) 14:20, 25 September 2019 (UTC)
- Okay, but I did one better than simple reversion. CapnZapp (talk) 15:42, 25 September 2019 (UTC)
User:GeoWriter, thank you for your edits. However, what you call repetition I call a summary. The way you phrased it, another editor can easily come along and think "why even mention the sunset thing, that's irrelevant" and remove the entire first paragraph. The way I phrased, I intentionally provided context to make it an organic whole. Since your edits are both well-intentioned and good I wanted to bring up this "stylistic" point here first. CapnZapp (talk) 10:25, 26 September 2019 (UTC)
- CapnZapp, I think that a non-standard section summary is not useful or necessary to counteract the possibility of an editor removing my first sentence about the sunset metaphorical non-volcanic usage if that editor does not bother to read my second sentence which is about the volcanic usage, but if it does happen, it can be fixed easily, without a section summary. It is interesting that you think that other editors will remove the metaphorical sunset usage if the volcanic usage is not explained in the same paragraph. The relevance of the sunset metaphorical usage does not depend on the volcanic usage being explained in the same paragraph (your approach) or in the following paragraph (my approach) because there is actually no known link betweeen these two uses. The reason for the precarious status of the sunset metaphor's inclusion and its high risk of removal is that its inclusion adds nothing to the volcanic usage which is the subject of this article. There is no evidence that e.g. the Horizon production team or other geologists knew about the 1925 metaphorical usage and got the idea of using the term "supervolcano" from Bridgeman. The sunset metaphor seems to be a compeletely independent occurrence. It has already been removed once by User:Mikenorton, and perhaps he may wish to add more details here about why he removed the metaphorical usage. GeoWriter (talk) 20:23, 27 September 2019 (UTC)
- I just felt (and still think) that it was irrelevant to the topic of this article - a one-off metaphor that does not appear to have inspired any other usage, so why mention it? Presumably because it is mentioned by the source, something that we do not need to follow. Mikenorton (talk) 21:02, 27 September 2019 (UTC)
We would be remiss if we discuss the origin of the term "supervolcano" without mentioning the origin of the term "supervolcano." CapnZapp (talk) 21:21, 27 September 2019 (UTC)
- I disagree - it seems clear that the term had more than one origin - the metaphorical use did not lead to the volcanology usage. Mikenorton (talk) 21:53, 27 September 2019 (UTC)
VEI 7 and calderas
@Kent G. Budge, GeoWriter, and CapnZapp: It's not wrong as-is; I know of precisely zero VEI 7 eruptions which didn't involve caldera formation of some sort. If we want to talk about supervolcanic eruptions only, then we should make no mention of particular VEI values. This is also suggested by the fact that there's a possible VEI 9 eruption at the top of the list. What shouldn't happen is this silly edit war.--Jasper Deng (talk) 04:18, 1 October 2019 (UTC)
- "If we want to talk about supervolcanic eruptions only, then we should make no mention of particular VEI values." I'm good with that, particularly since there are known eruptions well under VEI 7 that have produced nice, round, if somewhat smaller, calderas. --Kent G. Budge (talk) 04:22, 1 October 2019 (UTC)
- Jasper Deng, I do not yet understand why you think that "highest recorded VEI" is better than "highest VEI". You claim that "there's a possible VEI 9 eruption at the top of the list" - which eruption and who claims it is VEI 9? Please tell me more about VEI 9. As far as I'm aware, currently, the Volcanic Explosivity Index has possible values of 0 to 8 - there is no VEI 9. VEI 8 is the "highest VEI"; "highest recorded" suggests that the VEI scale will be extended to VEI 9 or even higher, which I suspect is probably unjustified speculation (WP:CRYSTALBALL). I think "higest recorded" is confusing, misleading and unnecessary and should be changed to "highest". Are you confusing VEI and the volcanic magnitude scale, which can have values greater than 8? These scales are two different scales. I have been working on the basis that the current criterion for the highest explosivity value (VEI 8) is > 1012 m3 of ejecta (as defined by Newhall and Self, 1982). This means that any and every volcanic eruption in the past, present and future that ejects more material than this lower volume limit is a VEI 8 eruption. There is no upper limit for VEI 8, therefore VEI 9 or greater is not required.
- As far as VEI 7 and calderas are concerned, I am aware that VEI 7 eruptions form calderas, but how is that relevant to supervolcanoes and supereruptions as they are currently defined in this Wikipedia article? This Wikipedia article about supervolcanoes (not calderas) currently seems to be built around the claim/definition in the first paragraph (sourced from a USGS webpage) that supervolcanoes have had eruptions of VEI 8, thereby excluding eruptions of VEI 7 or lower. I think this article needs changes because VEI is a problematic and contradictory way of defining supereruptions and supervolcanoes. For example, VEI is a problem when trying to justify the inclusion of VEI 4 flood basalt eruptions of large igneous provinces. If supervolcanoes and supereruptions should not be defined by VEI, how should they be defined in this article? GeoWriter (talk) 20:56, 1 October 2019 (UTC)
- No, VEI is unbounded; see the talk page archives of the VEI article for extensive discussions of that. I’d say (and many sources say) the Long Valley Caldera is a supervolcano even though its ejecta volume is “only” 600 km3 (VEI 7). The USGS definition is too restrictive in practice. But what alternatives are there? Sources that call volcanoes like Campi Flegri supervolcanoes don’t justify why in terms of a definition. However, I have not seen effusive eruptions get considered supereruptions, other than maybe very extreme cases like the Deccan Traps.—Jasper Deng (talk) 21:12, 1 October 2019 (UTC)
- (edit conflict) Please read my revert comment again, GeoWriter. Everybody: I agree with Jasper Deng:
If we want to talk about supervolcanic eruptions only, then we should make no mention of particular VEI values.
CapnZapp (talk) 21:16, 1 October 2019 (UTC)
- As far as VEI 7 and calderas are concerned, I am aware that VEI 7 eruptions form calderas, but how is that relevant to supervolcanoes and supereruptions as they are currently defined in this Wikipedia article? This Wikipedia article about supervolcanoes (not calderas) currently seems to be built around the claim/definition in the first paragraph (sourced from a USGS webpage) that supervolcanoes have had eruptions of VEI 8, thereby excluding eruptions of VEI 7 or lower. I think this article needs changes because VEI is a problematic and contradictory way of defining supereruptions and supervolcanoes. For example, VEI is a problem when trying to justify the inclusion of VEI 4 flood basalt eruptions of large igneous provinces. If supervolcanoes and supereruptions should not be defined by VEI, how should they be defined in this article? GeoWriter (talk) 20:56, 1 October 2019 (UTC)
- Jasper Deng, I do not understand your statement "VEI is unbounded". Please give more details. I suggest that you try to explain with an example. You also wrote "VEI is unbounded" in your article edit summary (02:30, 30 September 2019) when you added VEI 9 to the table entry of Flat Landing Brook Formation. Your claim of VEI 9 appears to be unsourced. As I wrote in my Talk page message (20:56, 1 October 2019), values of VEI are 0 to 8 (source reference e.g. https://volcano.si.edu/E3/). Your claim of VEI 9 should be reliably sourced, corrected or removed. I have read Talk:Volcanic Explosivity Index and that discussion contains nothing that supports the claim that VEI > 8 is valid. I repeat, VEI 8 has no upper limit, therefore VEI 9 is not needed. Tilling (2009) wrote that the VEI scale is "open-ended" (source reference: https://www.adv-geosci.net/22/125/2009/adgeo-22-125-2009.pdf). This is consistent with VEI 8 having no upper limit; his statement does not have to imply that VEI 9, 10, 11 etc. are valid or should be valid. According to its creators (Newhall and Self, 1982), the VEI scale is a "semiquantitative compromise" not a strictly mathematical scale and they do not suggest that the scale should be extended to VEI 9 to cover eruptions of >10,000 km3. On the contrary, they actually state "Eruptions can be assigned a VEI on a scale of 0 to 8 (the maximum number of categories we could realistically distinguish)". GeoWriter (talk) 00:12, 2 October 2019 (UTC)
- While the Eastern canada is a Supervolcano , and we do know 12,000 cubic ash came out of it , we dont know if it was made by multiple super eruption in a short time or one large eruption , it is also the oldest super eruption so it makes it hard to tell , it is very anoying that there seems to be some proof that the VEI can and can not go past 8 , it is noted for this eruption is 12,000 cubic and around the size of yellowstone and toba , and that it was a super eruption... but never stated VEI8 or 9 , there is also the problem of this book stating that La Garita that only did 5,000 cubic is apperently a VEI9 i keep on hearing this alot from people, as for VEI7 it gets confusing that tv shows keep on stating they are supervolcano's i feel like we need a big talk about VEI scale and what is a super volcano , the can the VEI scale go past 8? and that does the supervolcano scale start at 7? or 8?Joshoctober16 (talk) 16:31, 2 October 2019 (UTC)
- Jasper Deng, I do not understand your statement "VEI is unbounded". Please give more details. I suggest that you try to explain with an example. You also wrote "VEI is unbounded" in your article edit summary (02:30, 30 September 2019) when you added VEI 9 to the table entry of Flat Landing Brook Formation. Your claim of VEI 9 appears to be unsourced. As I wrote in my Talk page message (20:56, 1 October 2019), values of VEI are 0 to 8 (source reference e.g. https://volcano.si.edu/E3/). Your claim of VEI 9 should be reliably sourced, corrected or removed. I have read Talk:Volcanic Explosivity Index and that discussion contains nothing that supports the claim that VEI > 8 is valid. I repeat, VEI 8 has no upper limit, therefore VEI 9 is not needed. Tilling (2009) wrote that the VEI scale is "open-ended" (source reference: https://www.adv-geosci.net/22/125/2009/adgeo-22-125-2009.pdf). This is consistent with VEI 8 having no upper limit; his statement does not have to imply that VEI 9, 10, 11 etc. are valid or should be valid. According to its creators (Newhall and Self, 1982), the VEI scale is a "semiquantitative compromise" not a strictly mathematical scale and they do not suggest that the scale should be extended to VEI 9 to cover eruptions of >10,000 km3. On the contrary, they actually state "Eruptions can be assigned a VEI on a scale of 0 to 8 (the maximum number of categories we could realistically distinguish)". GeoWriter (talk) 00:12, 2 October 2019 (UTC)
- Joshoctober16: Mason, Pyle and Oppenheimer (2004, page 738, Table 2) show that the La Garita caldera eruption has a magnitude of 9.1 to 9.2 not a VEI of 9 (its VEI is the maximum possible value of 8). The "popular science" book "Super Volcano: The Ticking Time Bomb Beneath Yellowstone National Park" about Yellowstone (including La Garita Caldera) by Greg Breining (a nature writer and journalist), is the current source cited to support a claim of VEI 9 for La Garita Caldera in its Wikipedia article. Volcanic eruption size has been misunderstood either by Breining or by the Wikipedia editor who used this source, or by both of these people.
- To repeat what I wrote in my comment of 01 October, the volcanic explosivity index (an integer number scale of 0 to 8) and the volcanic magnitude scale (a rational number scale with no maximum value) are different scales, admittedly very often wrongly assumed to be the same scale. (There is also a volcanic intensity scale, but it is probably best to ignore that third scale for now).
- Here are three source references supporting VEI having a maximum value of 8: (Ref A) "The volcanic explosivity index ... uses an integer scale from 0 to 8 to describe both the volume and plume height of any given eruption"; Pyle, D.M. "Sizes of Volcanic Eruptions" in Sigurdsson, H. et al. (editors) (2000) "Encyclopedia of Volcanoes", Academic Press, pages 263–264). (Ref B) "VEIs range ... to 8 (the largest eruptions in Earth's entire history)"; https://volcano.si.edu/E3/ Smithsonian Institution, Global Volcanism Program, Eruptions, Earthquakes & Emissions, Frequently Asked Questions. (Ref C) "The most widely used index of volcanic size is the 'volcanic explosivity index' (or VEI) of Newhall and Self (1982). The VEI is a semi-quantitative logarithmic scale of eruption size, based on a combination of erupted tephra volume and eruption plume height. On this scale, the largest events (VEI 8) are defined as eruptions with bulk tephra volumes >1,000 km3". ; Mason, B.G.; Pyle, D.M. and Oppenheimer, C. (2004) "The size and frequency of the largest explosive eruptions on Earth", Bulletin of Volcanology, volume 66, pages 735–748, DOI 10.1007/s00445-004-0355-9. — GeoWriter (talk) 17:52, 5 October 2019 (UTC)
Known super VEI 7 eruptions
My removal of VEI 7 eruptions was reverted. My rationale is simple: this article is specifically about supervolcanoes defined to be VEI 8, thus making the list off topic for this article.
Please argue here why we should keep the VEI 7 list. Thank you CapnZapp (talk) 07:03, 12 October 2019 (UTC)
- Three days later no such arguments have been introduced. Re-removing VEI 7 eruptions, at least for now. If/when the community agrees VEI-7 are supervolcanoes too (see below section), feel free to reinstate the VEI-7 section. Regards, CapnZapp (talk) 17:39, 15 October 2019 (UTC)
- We have a presumably reliable source (the USGS web page) defining a supervolcano as a VEI 8 eruption. Why is there still a "disputed - discuss" tag on this statement in the opening sentence of the article? --Kent G. Budge (talk) 17:43, 21 January 2020 (UTC)
- See the section below this one ("Definition of article subject") CapnZapp (talk) 17:48, 21 January 2020 (UTC)
- We have a presumably reliable source (the USGS web page) defining a supervolcano as a VEI 8 eruption. Why is there still a "disputed - discuss" tag on this statement in the opening sentence of the article? --Kent G. Budge (talk) 17:43, 21 January 2020 (UTC)
Definition of article subject
The reversion by editor 82.24.197.201 of CapnZapp's removal of VEI 7 eruptions has, unfortunately, re-introduced the inconsistency between the article's first sentence (that supervolcanoes are volcanoes that have had a VEI 8 eruption) and the inclusion of VEI 7 eruptions in the main body of the text. I've flagged the definition as "disputed-discuss" and "contradictory" to encourage editors to discuss the definition and scope of which eruptions should be included in this article. — GeoWriter (talk) 16:20, 12 October 2019 (UTC)
- Comment: I took the liberty of splitting out your post, GeoWriter, into its own section. Cheers, CapnZapp (talk) 17:39, 15 October 2019 (UTC)
- It seems hard to do better than the definition at the USGS site, which defines a supervolcano as a VEI 8 eruption. Is there any other reliable source that defines it otherwise? If so, let's note the conflicting definitions within the geology community in the article lede. If not, re-re-revert to CapnZapp's version that removes VEI 7 eruptions. — Preceding unsigned comment added by Kent G. Budge (talk • contribs) 20:19, 21 January 2020 (UTC)
Flat Landing Brook - Explosive or Effusive?
In the thread above about VEI 9 eruptions (Not the one directly above this thread, the one way up the Talk page), Wikipedians were discussing about the Flat Landing Brook eruption, and whether or not we should add the classification of VEI 9. One of them said that The Flat Landing Brook eruption was actually multiple events and that those were effusive:
"Clearly not a single eruption. FLB is a huge volcanic formation, but it's consisted of lava flows and pyroclastics in mafic and felsic compositions, and sedimentary rocks. It's possible that some layers of felsic pyroclastics were equally as large as Yellowstone or Toba, but FLB was not formed in a single event.--13:05, 14 July 2020 (UTC)Aleral Wei (talk)"
If so, then should we remove the Flat Landing Brook eruption from the explosive eruptions section of List of largest volcanic eruptions and move it to the Non explosive eruptions section? I would like to have your opinions down below. The Space Enthusiast (talk)
VEI 9?
The VEI scale goes up to 8 and no further. There is an eruption magnitude measure that goes up to and beyond 9, but that is not the same as VEI. The recent change to the Fish Canyon Tuff entry, adding a VEI 9 section is not supported by a reliable source - that's a book by a journalist, not a volcanologist. Mikenorton (talk) 12:25, 7 September 2019 (UTC)
- 5,000 Km of ash is not what a VEI9 would be if a 9 exist , however there is a supervolcano in eastern canada with a possible 12,000 Km ash area , problem is its super old , and hard to for sure tell if it was from one eruption or a lot of 2,000 km ash under 2 million years https://en.wikipedia.org/wiki/Flat_Landing_Brook_Formation. Joshoctober16 (talk) 17:11, 7 September 2019 (UTC)
- Clearly not a single eruption. FLB is a huge volcanic formation, but it's consisted of lava flows and pyroclastics in mafic and felsic compositions, and sedimentary rocks. It's possible that some layers of felsic pyroclastics were equally as large as Yellowstone or Toba, but FLB was not formed in a single event.--13:05, 14 July 2020 (UTC)Aleral Wei (talk)
- Previous timestamp malformed. This edit's timestamp should make the section autoarchive properly. CapnZapp (talk) 15:30, 19 October 2020 (UTC)
- Clearly not a single eruption. FLB is a huge volcanic formation, but it's consisted of lava flows and pyroclastics in mafic and felsic compositions, and sedimentary rocks. It's possible that some layers of felsic pyroclastics were equally as large as Yellowstone or Toba, but FLB was not formed in a single event.--13:05, 14 July 2020 (UTC)Aleral Wei (talk)
Interventions
Should we add something about possible interventions to prevent/delay/mollify a supervolcano eruption? According to this paper[1]
The two most promising interventions involve putting more pressure on the magma and delaying the eruption with water dams or soil over the magma chamber. We perform a technical analysis, accurate to within an order of magnitude, and find that water dams and soil and could statistically delay the eruption for a century with 1 and 15 years of effort, respectively. All actions require essentially untested geoengineering challenges along with economic, political and general public acceptance.
Crust (talk) 17:15, 15 August 2021 (UTC)
References
Large Igneous Provinces
There does not appear to be a consensus among geophysicists that Large Igneous Provinces are considered supereruptions, and therefore should not properly be called supervolcanoes. This is apparently due to the the differing natures of the eruptions. A well elucidated explanation for this, citing an academic source, is found on Quora...
"Though more destructive on a planetary scale than the highest level on the volcanic explosivity index, VEI 8, large igneous provinces such the Siberian traps are not catalogued in the same scale by volcanologists. This is because, though exhibiting explosive episodes, gigantic, near continent-wide shield volcanoes erupt over a much greater time-scale rather than the chronologically more brief , generally more intense upheaval of a super eruption.
Again, though explosions have happened during LIP episodes, overall they are characterised as basaltic, less viscous flows. This is similar to volcanics at Hawai’i though on a much larger scale.
Large Igneous Provinces (LIP) are concentrated periods/areas for volcanism on earth and are closely related to super-eruptions.
But they are not called super eruptions by geophysicists. In my link below there’s a quote from the august Volcanoes of the World which addresses the different lists, professionally.
https://pages.mtu.edu/~raman/VBigIdeas/LIPS!.html"
I acknowledge that Quora is not a reliable source for academic standards of referencing, however the source cited is. It makes clear that LIP's are related to, but not the same, as supereruptions. Most lists of prominent supereruptions do not include any LIP's, the Siberian Traps being the most obvious example, being responsible for far more deposits than any of the supereruptions listed on the page, albeit over a much longer period of time. I feel the page would better reflect the way these types of events are cataloged if it was changed to refer to LIP's as related to, also of massive scale, but fundamentally different to supereruptions. — Preceding unsigned comment added by 2407:7000:AA1C:2200:CEA:1E5:29EB:9C2A (talk) 21:41, 3 May 2022 (UTC)
- I think the instinct is right here, that large igneous provinces are close to synonymous with very extensive flood basalts, while supereruptions are nearly synonymous with large caldera eruptions of a felsic nature. I'll see if I can find some authoritative sources on the distinction. Incidentally, a university website is not necessarily a reliable source, and I'd probably cross-check even Volcanoes of the World. --Kent G. Budge (talk) 23:12, 3 May 2022 (UTC)
- Many LIPs contain a significant component of silicic volcanism. This paper details a series of silicic supereruptions from the Ethiopia-Yemen Continental Flood Basalts province, with four of them exceeding 1,000 km3 Dense Rock Equivalent (DRE) in volume. Mikenorton (talk) 09:00, 4 May 2022 (UTC)
- Not disputing that at all, but the issue is more one of how they are typically cataloged. Typically, lists you'll find when searching supervolcanoes exclude LIP's which instead appear on their own separate lists. This suggests there is not a consensus that LIP's should be included as supervolcanoes (which is not to say that some in the field do not include them, just that it is not universally accepted). There is also a practicality issue related to the scale of events given the purpose of the term supereruption appears to be largely to differentiate the largest eruptions from smaller eruptions, yet the largest supervolcanoes listed on this page pale in comparison to continent spanning LIP's. They are just fundamentally different types of events in nature and scale. Grouping them together doesn't make a whole lot of sense and the absence of LIP's from lists at least implies, even if it's not explicitly stated, that there are other criteria for inclusion in the supervolcanos group. At the very least the page should attempt to address the issue of why the largest eruptions using the criteria offered on the page do not appear on the list of eruptions on the same page. Basically, it's a very confused issue for a layman such as myself trying to understand it when reading this page. 2407:7000:AA1C:2200:19C6:E828:4798:90A5 (talk) 22:23, 4 May 2022 (UTC)
- Sorry, I think what I wrote was a little unclear. I am not suggesting that wikipedia should attempt to redefine the terminology, that wouldn't be appropriate obviously. I am suggesting that the way the terminology is applied seems to not always be consistent with its definition, as evidenced by the list on the page and other sites. That was a source of a great deal of confusion for me when researching the subject and suggests the article could be improved by addressing the issue in an appropriate manner. 2407:7000:AA1C:2200:19C6:E828:4798:90A5 (talk) 22:36, 4 May 2022 (UTC)
- Not disputing that at all, but the issue is more one of how they are typically cataloged. Typically, lists you'll find when searching supervolcanoes exclude LIP's which instead appear on their own separate lists. This suggests there is not a consensus that LIP's should be included as supervolcanoes (which is not to say that some in the field do not include them, just that it is not universally accepted). There is also a practicality issue related to the scale of events given the purpose of the term supereruption appears to be largely to differentiate the largest eruptions from smaller eruptions, yet the largest supervolcanoes listed on this page pale in comparison to continent spanning LIP's. They are just fundamentally different types of events in nature and scale. Grouping them together doesn't make a whole lot of sense and the absence of LIP's from lists at least implies, even if it's not explicitly stated, that there are other criteria for inclusion in the supervolcanos group. At the very least the page should attempt to address the issue of why the largest eruptions using the criteria offered on the page do not appear on the list of eruptions on the same page. Basically, it's a very confused issue for a layman such as myself trying to understand it when reading this page. 2407:7000:AA1C:2200:19C6:E828:4798:90A5 (talk) 22:23, 4 May 2022 (UTC)
- Many LIPs contain a significant component of silicic volcanism. This paper details a series of silicic supereruptions from the Ethiopia-Yemen Continental Flood Basalts province, with four of them exceeding 1,000 km3 Dense Rock Equivalent (DRE) in volume. Mikenorton (talk) 09:00, 4 May 2022 (UTC)