Talk:Newberry Volcano

once world's tallest mountain?
Someone told me that Paulina peak was at one time the world's tallest mountain. Has anyone else heard this? 66.195.36.133 (talk) 20:29, 10 February 2009 (UTC)


 * I had not heard that before. When I first saw your note, I highly doubted it.  But after reading the Smithsonian summary, it's not so hard to believe that a 22.5 km wide volcano with such unusual lava composition could well have been quite tall.  —EncMstr (talk) 20:46, 10 February 2009 (UTC)


 * This is very, very unlikely. To add enough height to surpass Everest, it would make Newberry's pre-erupted summit abnormally tower-like. Mountains just don't exist like that. Especially with volcanoes. Leitmotiv (talk) 04:09, 28 February 2010 (UTC)
 * Mauna Kea is the world's tallest mountain. Of course, that's counting the massive height which is not above sea level. —Preceding unsigned comment added by Guanlongwucaii (talk • contribs) 12:31, 7 March 2010 (UTC)

Yellowstone hotspot
The Newberry volcano gets magma from the Yellowstone hotspot (it is the residuum of the Yellowstone hotspot plume, subduction counterflow of the subduction). As the oceanic accreation belt is less thick than the North American craton and the magma in its bouyancy spills on the westside of the margin. As I understand, the sequence of events were, more or less: fast convergence of the Farallon plate, Laramide orogeny, accreation of the mid-ocean ridge, end of the convergence and San Andreas transform fault, Basin and Range province extension (geology), Columbia River and Steens flood basalts, Snake River - Yellowstone volcanic province and Newberry shield volcano.
 * Pages: 28, 50 and 51.
 * --Chris.urs-o (talk) 05:58, 28 July 2010 (UTC)
 * --Chris.urs-o (talk) 05:58, 28 July 2010 (UTC)
 * --Chris.urs-o (talk) 05:58, 28 July 2010 (UTC)


 * The first reference explicitly does not address whether the Newberry magma comes from the Yellowstone hotspot:
 * We also note that the northwest time-progression of the Newberry silicic volcanic system and the Oregon High Lava Plains (Jordan et al., 2004; Camp and Ross, 2004) (Fig. 2) has been argued by some as a “mirror” image of the volcanic processes of the YSRP. However, we will not include a discussion of this volcanic system as it is beyond the scope of our study
 * A mirror image is not the same as sharing the same magma source. I don't have immediate access to the other two sources. —hike395 (talk) 02:37, 29 July 2010 (UTC)


 * Wiki text quote: "The exact reason for this is unknown, but it appears..." It is a very open formulation. If Newberry gets its magma mainly from Yellowstone or from the subduction of the Juan de Fuca plate does not matter much to me. The figure #26 on page 51 of ref. one are from Camp & Ross, 2004. Figure #25 on page 50 and figure #2 on page 28 are important too. Robert B. Smith is the University of Utah Coordinating Scientist for Yellowstone Volcanic Observatory, he should know Yellowstone. The Newberry silicic volcanic system has a 10 Ma history, wandering westwards. --Chris.urs-o (talk) 04:41, 29 July 2010 (UTC)


 * Two problems with the section that I attempted to fix:
 * The papers that I could find (including Camp and Ross) do not support the fact that variability of Newberry magma is due to its hotspot origins. In fact, I can find no papers that really analyze the variability. So, I edited out the reason.
 * The following paragraph contradicted the previous one and said that Newberry could not be caused by a mantle plume. It's clearly a controversy that needs to be discussed, so I presented both the pro-plume and anti-plume sides. I used Camp and Ross as a citation for the pro-plume side, since it goes into a little detail about Newberry and the shearing of the plume.
 * —hike395 (talk) 10:54, 29 July 2010 (UTC)


 * Hi Chris. Thought I should caution both of you that the general trend of scientific thinking (such as I have seen) is distinctly unsettled regarding both Newberry and the YHS.  You should take a look at Xue & Allen 2006; Christiansen & others 2002; Shervais & Hanan 2008; and Zandt & Humphreys 2008.  Full references at Olympic-Wallowa Lineament. - J. Johnson (JJ) (talk) 17:46, 11 August 2010 (UTC)


 * A similar volcano in Northern California, Medicine Lake Volcano, is noted as being apart of the Cascades (noted by a USGS Geologist). It is similarly offset from Mount Shasta, like Newberry. Both Newberry and Medicine Lake are huge shield volcanoes of similar proportions. I'd keep it apart of the Cascades.Leitmotiv (talk) 20:45, 11 August 2010 (UTC)
 * It seems to me that we have some subduction counterflow and back arc basin extension here. Sorry JJ I saw ur note just now. By the way, Robert B. Smith is the University of Utah Coordinating Scientist for Yellowstone Volcanic Observatory (YLO), Robert L. Christiansen (USGS) was YVO Scientist-in-Charge. --Chris.urs-o (talk) 04:18, 12 August 2010 (UTC)


 * --Chris.urs-o (talk) 11:13, 15 August 2010 (UTC)
 * Interesting papers JJ, especially Zandt & Humphreys (2008). --Chris.urs-o (talk) 15:52, 24 August 2010 (UTC)
 * --Chris.urs-o (talk) 11:13, 15 August 2010 (UTC)
 * Interesting papers JJ, especially Zandt & Humphreys (2008). --Chris.urs-o (talk) 15:52, 24 August 2010 (UTC)
 * --Chris.urs-o (talk) 11:13, 15 August 2010 (UTC)
 * Interesting papers JJ, especially Zandt & Humphreys (2008). --Chris.urs-o (talk) 15:52, 24 August 2010 (UTC)

Broaden geological view?
The geology section seems (to me, at least) too narrowly, too myopically focused on just local and recent geology of the volcano itself. I'm thinking it should be broadened a bit to show how it fits into the broader regional context of the High Lava Plains, the Brothers Fault Zone, Basin and Range Province extension (which is not adequately covered in B&R itself), and perhaps the overall connection with the YSH. Comments? - J. Johnson (JJ) (talk) 20:49, 12 October 2010 (UTC)


 * I think that Basin and Range Province needs a fair amount of love from a geologist: it has very little about the origin of the topography. I would recommend placing the context into that article, and then refer to it using the main template, with a short summary here. (see WP:SUMMARY)


 * The geological cause of the B&R is still under debate, right? I've heard of the slab gap hypothesis, but is that very commonly accepted, or are there reasonable alternatives? —hike395 (talk) 09:14, 13 October 2010 (UTC)
 * Yes, B&R needs some work. Which I am thinking of stepping up to.  The basic fact of B&R topography is that it exhibits — is due to — regional extension. (Simple!)  The underlying (ha ha) question is, what drives the extension?  That is where the debate comes in.  And, yes, there are plausible rival theories.
 * What I have in mind for here is fairly short paragraph on Newberry's relation to the High Lava Plains and the Brothers Fault Zone -- that is the necessary context -- and just a passing mention that all this occurs in a broader context of the B&R. That should give sufficient (albeit minimal) context. - J. Johnson (JJ) (talk) 19:59, 13 October 2010 (UTC)


 * Basin and Range Province, I thought that:
 * Farallon Plate slab breaks off, Laramide orogeny ends.
 * Pressure releases, extension (geology) by gravity.
 * There is a slab gap hypothesis and a Mid-Tertiary ignimbrite flare-up.
 * --Chris.urs-o (talk) 22:33, 13 October 2010 (UTC)
 * Chris, there is a LOT of literature about the B&R and related topics (which is a principal reason I have always shied away from it), and I couldn't begin to sort out the many different theories that have been proposed. If you're curious, I would suggest a careful read of Xue and Allen (above), and also the Camp & Hanan paper cited in Brothers Fault Zone.  Even those are just one corner of the literature.
 * BTW, I keep forgetting to ask if all you volcano enthusiast know that the USGS has some good bibliographies on the topic. E.g., OFR 00-017 (covering 1990-1997). - J. Johnson (JJ) (talk) 19:13, 14 October 2010 (UTC)
 * BTW, I keep forgetting to ask if all you volcano enthusiast know that the USGS has some good bibliographies on the topic. E.g., OFR 00-017 (covering 1990-1997). - J. Johnson (JJ) (talk) 19:13, 14 October 2010 (UTC)


 * Okay, I've got some new material, and an new figure, will be uploading in a day or three. What I am going to do is rewrite the "hotspot" section and insert it at the top of "geology".  It should work good.
 * I also suggest we drop the "geothermal" section. Right now it's just one mention of a was-coming commercial event, based on a single newspaper story.  If someone wants to work on that section I can suggest some references, but I rather doubt there is enough substance to warrant a section. - J. Johnson (JJ) (talk) 23:03, 19 October 2010 (UTC)
 * P.S.: I forgot to mention that I also want to revise the citations. Basically, pull the cite/citation templates with all the bibliographic details out of text, and collect them in the References section; replace the textual citations with Harv templates.  I don't know if that frightens anyone, but don't worry, it will work out just fine.  Ask if you have questions.
 * - J. Johnson (JJ) (talk) 23:14, 19 October 2010 (UTC)
 * I am looking forward to seeing what you add. Thanks for taking the time and effort to enhance this article.  —EncMstr (talk) 00:27, 20 October 2010 (UTC)
 * Done. I trust that will be satisfactory to everyone.  BTW, some of you guys (gals?) have been getting a bit careless with your citations.  The new arrangement (with all the cite templates collected in "References") should make them clearer in respect of completeness and consistency, and even easier to do, but you still need to take time do all the bit-fiddling parts.  - J. Johnson (JJ) (talk) 22:34, 21 October 2010 (UTC)
 * And I see that SmackBot has already merged some of the references. Named references are an abomination, as they entangle the relationships between the citations and the material, and it is a disservice that Smackbot automatically enforces this.  The only way I have found to avoid such diddling is to make each ref unique in some trifling way.  This can be good, in encouraging use of specific page numbers to locate cited material, but as I did not do the initial research I may have to fake it. - J. Johnson (JJ) (talk) 18:58, 23 October 2010 (UTC)

Caldera formation
If you simply read the cited source, it explicitly describes flank eruptions that removed the support of the summit of the volcano; calderas do not require explosive eruptions to form, with most shield volcanoes' calderas forming this way as well. The cited source Fire Mountains of the West, which I physically have on me, states pretty clearly that Newberry is considered a composite cone despite having lots of characteristics of a shield volcano.--Jasper Deng (talk) 10:33, 5 February 2018 (UTC)
 * I believe Hildreth et al. (2007) also states that it's a stratovolcano.  ceran  thor 16:08, 5 February 2018 (UTC)


 * My understanding is that it is a shield volcano. Perhaps we should review the literature and see what the scientific consensus is? Or has been, allowing there may have been a shift in recent years. ~ J. Johnson (JJ) (talk) 21:54, 5 February 2018 (UTC)
 * Donnelly and Nolan (2011) list it as a "shield-shaped composite" volcano (page 2 here). Similarly, Hildreth (2007) writes the following: "Although Newberry takes the form of a great shield volcano 35×65 km across, it is a profoundly hybrid edifice. Capped by a 5×7-km late Pleistocene caldera, the edifice has a rhyolite-rich core surrounded by a gently dipping apron sprinkled with more than 400 mafic scoria cones and fissure vents along with about 20 silicic flank domes (MacLeod and others, 1995). Many more domes and cones are likely to be concealed beneath the mantle of thin mafic lavas and mafic-to-silicic pyroclastic deposits that smooths the surface and conveys a deceptive integrity to the edifice, which is in large part a distributed volcanic field that surrounds and interfingers with products of the central volcano" (see page 41 here).  ceran  thor 22:08, 5 February 2018 (UTC)


 * Jasper Deng, I've done more than read the cited sources, I've had direct conversations with Julie and have helped her in her research of Newberry, as she's helped me with mine. But suffice it to say, Newberry is an explosive volcano, probably a composite, but still also a shield volcano as evidenced by all the lava flows originating from it. It blew its top like Mazama that gave rise to its own term like Mazama Ash, called Newberry Ash. Newberry Ash is used extensively to determine the age of the lava flows on and around Newberry. The ash signifies explosive elements in which the caldera was formed. Most of the lava flows are parasitic in nature and are not directly related to the caldera in any direct way, afaik. Also, Fire Mountains of the West is outdated in a big way and is for laymen, mostly. Leitmotiv (talk) 22:23, 5 February 2018 (UTC)
 * Good to know. I've found it increasingly less useful as I've been writing Cascade articles. Thanks for your input, Leitmotiv. Would you be willing to work with me to find a way to express that it's both a shield and composite volcano without being overly confusing to a lay reader?  ceran  thor 22:34, 5 February 2018 (UTC)
 * Ceranthor, I think I can help very little honestly. What I do know from Julie could be considered original research, since most of it is unpublished. Most of the stuff I was involved with involved the Horse Lava Tube System and the Arnold sytem. Julie has published a few abstracts and field guides for Newberry, but her final map and paper are still probably a few years out yet. I've been waiting since about 2007 when I initiated contact with her. Most of the guides Julie has told me about are available here in J2. Her latest abstract is available here: http://iavcei2017.org/ Leitmotiv (talk) 22:47, 5 February 2018 (UTC)
 * Understood. What's J2?  ceran  thor 22:53, 5 February 2018 (UTC)
 * If you click the link you will see more links, follow Chapter J2 for Newberry field guide by Julie and Bob Jensen. I like her little mention of "including explosive activity" for Newberry in J2... Leitmotiv (talk) 23:03, 5 February 2018 (UTC)
 * Is the Freakonomics link the correct one?  ceran  thor
 * Nope! Sometimes my copy/pasta button don't work quite right. Fixed it for you. Yeah the field guide specifically states: " At the center of the volcano is the 6- by 8-km caldera, created ~75,000 years ago when a major explosive eruption of compositionally zoned tephra led to caldera collapse, leaving the massive shield shape visible today." Leitmotiv (talk) 23:21, 5 February 2018 (UTC)
 * I'll go through asap and see what I can do. I think what's in the article is all factually correct, we probably just need to clarify the shield-like activity a bit more.  ceran  thor 01:52, 6 February 2018 (UTC)
 * It looks to me like they're saying it has "shield volcano"-like qualities. It's similar to shield volcanoes because it has dozens and dozens of lava flows on its flanks just like a shield volcano, however, it has a core like a composite volcano. The part I'm confused about it is how the caldera is shield-shaped too. I think the closest analog to Newberry is Medicine Lake Volcano. The biggest difference between Medicine Lake and Newberry is that Newberry has a long history of explosiveness, making it similar to Mazama, but it is similar to Medicine Lake in all other regards I believe. Leitmotiv (talk) 02:00, 6 February 2018 (UTC)
 * I would hold a neutral point of view and simply claim that Newberry Volcano has been described as a shield volcano or a stratovolcano. Volcanoguy 21:13, 7 February 2018 (UTC)
 * At the risk of exposing my ignorance on the topic: does this strato/shield ambiguity of Newberry distinguish it from other Cascade volcanoes? In that case it would relevant to describe it. If there has been scientific controversy about it then that would be an opportunity to explain how it is that scientists differ, and how science eventually resolves such issues. ~ J. Johnson (JJ) (talk) 22:01, 7 February 2018 (UTC)
 * According to this discussion some scientists consider Newberry a shield volcano while others consider it a collapsed stratovolcano/composite volcano. I'm just saying if there is controversy over the matter then both sides should be represented in the article rather than arguing over which one is correct. Volcanoguy 00:40, 11 February 2018 (UTC)


 * Whatever the eruption type, it is factually correct that a caldera is created by the removal of support due to magma withdrawal, so either way my edit was correct, except about flank eruptions. There is a cited source that clearly refers to flank eruptions, not a central vent one. Perhaps it is also ambiguous because there are multiple calderas in question here.--Jasper Deng (talk) 05:00, 6 February 2018 (UTC)
 * A caldera may collapse because of lack of support, but that is not the only cause, and certainly isn't the case for Newberry's main collapse. Either way, the source I've provided is the most up to date science and is published by the leading scientist on Newberry, as opposed to a newspaper source (Oregon Live) which are notoriously error prone and really aren't an authority on anything unless they are citing another source. Leitmotiv (talk) 07:04, 6 February 2018 (UTC)
 * A caldera is by definition a collapse depression, otherwise it's simply a "crater", not including erosional calderas like Mount Tehama.--Jasper Deng (talk) 08:01, 6 February 2018 (UTC)
 * Barring exceptions, I guess these scientists don't know what they're talking about. Leitmotiv (talk) 20:00, 6 February 2018 (UTC)
 * Leitmotiv, Jasper Deng, J. Johnson (JJ), and Volcanoguy: before I get around to changing anything, I want to clarify the argument. Would describing the article as a hybrid of a shield and stratovolcano (or composite volcano), with characteristics of both, be considered appropriate by all of you?  ceran  thor 01:17, 11 February 2018 (UTC)
 * I have no objections, up to date sources support such an edit. Leitmotiv (talk) 19:35, 11 February 2018 (UTC)
 * Frankly: I don't know. I think we need someone to review the latest sources and see what they say. Perhaps even check with the local volcanology community (I believe some of you are well placed for that, right?) to see what the sense of the matter is. I suspect that we could find sources supporting either view, so a key consideration is that we have not simply supporting sources, but a broad view of the matter. And if there has been controversy on this point then (as I said above) it might interesting to describe that. Even though we can't cite a "personal communication" with an expert, it's still good to have some "ground truth". ~ J. Johnson (JJ) (talk) 21:37, 11 February 2018 (UTC)
 * I see that most of the sources call it a composite volcano with shield volcano characteristics. I think that I am using most of the most up-to-date sources (though I may be wrong in that belief), and I think describing it as having characteristics of both properly reflects all the literature I've encountered thus far. I am happy to continue discussing this here and letting others reach out to experts to clarify, though.  ceran  thor 22:38, 11 February 2018 (UTC)
 * I think a check would still be good. But I have no qualms with whatever changes you make. ~ J. Johnson (JJ) (talk) 00:03, 12 February 2018 (UTC)
 * I'm not sure what you mean by checking with the "local volcanology community". What locale? Wikipedia? Also consider that everything on Wikipedia should be cited anyway, and I've supplied Ceranthor with scientific links to the latest information on Newberry from the leading geologist working it these past years. Not sure how you can get much better than that, at the moment. Leitmotiv (talk) 19:16, 12 February 2018 (UTC)

Leitmotiv, Jasper Deng, J. Johnson (JJ), and Volcanoguy - I've listed the article at peer review, if you want to provide further input. I am hoping to take the article to FAC in the next month or two.  ceran  thor 19:20, 29 January 2019 (UTC)
 * An update


 * Leitmotiv said he's given you the latest links as of a year ago; is there anything of interest there? You might supplement that with a literature search to see what's new. Don't forget the abstracts; they are excellent "leading indicators". Perhaps anything of possible interest could be listed here for consideration. And for sure, don't rely on the popular media for anything that has been studied scientifically. &diams; J. Johnson (JJ) (talk) 23:26, 29 January 2019 (UTC)
 * I don't have any new links to give. But you could check the Horse Lava Tube System/Arnold Lava Tube System articles for stuff by Donnelly-Nolan and Champion if you are inclined. It's fairly narrow stuff, but maybe you can find something in there. Overall great work. Leitmotiv (talk) 00:27, 30 January 2019 (UTC)


 * P.S. If you're going for FA perhaps all those named-ref short cites should be split part. It would be nice to have a script for doing that (maybe someday), but the editor's search & replace function could probably ease the work. &diams; J. Johnson (JJ) (talk) 00:39, 30 January 2019 (UTC)

Contradictory information
There appears to be some contradictory information in the Geology section about when (and how) Newberry Caldera formed.

One paragraph says this:

The caldera-forming event occurred about 75,000 years ago from a major explosive eruption.[49] It formed the crater lakes and Paulina Peak...

I checked the citation (Jensen & Donnelly-Nolan 2017), and it does say that the caldera formed in an event about 75,000 years ago, but this contradicts the cited information in the very next paragraph of the article as follows:

''The caldera has reformed several times throughout the volcano's history ... The first caldera—the volcano's largest caldera, forming approximately 300,000 years ago—was produced by the eruption of 2.5 cubic miles (10 km3) of pyroclastic ejecta, which created the Tepee Draw tuff and ash deposits that cover the volcano's eastern flank.[51] The last crater formed after an explosive eruption about 80,000 years ago ... [55] Since the last caldera-forming eruption 80,000 years ago...''

I don't have access to Harris 2005, but perhaps someone who does could reword one or both of these paragraphs to clarify?

Ddaveonz (talk) 10:40, 28 July 2020 (UTC)


 * There has likely been more than one caldera forming event. The most recent being the one 75,000 years ago. Donnelly-Nolan is the authoritative source on the matter as she is the leading geologist from the USGS studying it, but I don't know what other abstracts she's released regarding these events. Until we can access Harris, it's best we leave it as is. Leitmotiv (talk) 19:36, 28 July 2020 (UTC)
 * Her paper mentions at least 3 caldera forming events, the most recent being 75,000 years ago. I find it interesting that Donnelly-Nolan doesn't reference Harris in her work, at least in the papers I am reading. Leitmotiv (talk) 19:53, 28 July 2020 (UTC)

Areal extent
The article claims Newberry has an area of 1,200 sqmi when its lava flows are taken into account. What it didn't include, however, was its true areal extent of 620 sqmi which still needs to be worked into the article somehow. I included it with this edit but the rest of the article including the volcano's length are based on the inclusion of lava flows. If you look at File:Newberry Volcano Map.png you can see the actual volcano (dark gray) has a length of about 40 miles instead of 75 miles. The 1992 Volcanoes of North America book used as a source in this article gives Newberry's areal extent as 620 sqmi, as does this 1999 USGS document and the GVP website. Volcanoguy 08:16, 5 September 2021 (UTC)