Talk:Lava

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High iron lavas[edit]

No mention is made of the fact that both aa and pahoehoe are strictly high-iron lavas, which are much less viscous than high-silica lavas. Ideally I'd like to see a chart of the ferromagnesium silicate range (from ultramafic to ultrasilicic), identifying the ranges which produce each type of lava. Also, the section 'composition of lavas' is not actually about the composition of lavas. It should be. --Leperflesh 01:09, 7 December 2005 (UTC) And also adding the fact that when lava come out it turnes into lava from magma — Preceding unsigned comment added by Toolman34 (talkcontribs) 22:03, 28 November 2012 (UTC) good — Preceding unsigned comment added by 117.203.69.120 (talk) 16:14, 14 January 2013 (UTC)[reply]

Hawaii pictures[edit]

There are far too many examples of lava from Hawaii, can we flease not have pictures from other volcanoes. I know its easy to see lava on Hawaii but that not excuse for having 9 of 13 pictures from Hawaii. If nobody complains I will start to globalize the pictures and put the "excess" pictures in a gallery in the bottom of the page.Dentren | Talk 23:10, 15 October 2009 (UTC) Well I guess I just screwed up. I added yet another. If members object by all means remove. It is in the hazard section. That would be me in the picture. I'm adding another on the lava bench page. Pbmaise (talk) 11:54, 6 June 2011 (UTC)[reply]

I have no issue with more pictures from around the world, but do remember that Hawaii is the place where several types and features of lava were originally defined. A'a and pahoehoe pictures should be from Hawaii because that is where the type examples are. Elriana (talk) 02:29, 21 June 2013 (UTC)[reply]

Edit request from Cpuaggie, 4 October 2010[edit]

{{edit semi-protected}} In the article's list of references, reference "14. ^ a b Lava Flows and Their Effects USGS," the current hyperlink:

"http://volcanoes.usgs.gov/hazards/What/Lava/lavaflow.html"

is a dead link leading to an error page at the USGS website. After doing a little searching, I found what I believe to be the updated web address that the hyperlink was originally intended to re-direct to:

"http://volcanoes.usgs.gov/hazards/lava/index.php"

Cpuaggie (talk) 06:08, 4 October 2010 (UTC)[reply]

Done Thanks, Stickee (talk) 06:23, 4 October 2010 (UTC)[reply]

Note sure about this, but in lava fountains it's worth noting that the 1783 laki eruption had probably the highest fountains on record http://en.wikipedia.org/wiki/Laki so worth adding . — Preceding unsigned comment added by 82.27.29.211 (talk) 12:16, 19 September 2014 (UTC)[reply]

Protected page[edit]

Is there a reason for protecting this page from IP editors? Jim.henderson (talk) 01:40, 27 February 2011 (UTC)[reply]

Seems it was quite a target for vandalism and was semi'd last March. Check the history. Vsmith (talk) 03:12, 27 February 2011 (UTC)[reply]

Wasn't that a long time ago, by the usual standards for such cases? Jim.henderson (talk) 22:23, 28 February 2011 (UTC)[reply]

Seeing as its been years since there has been any vandalism, should the protection be removed now? Jcmcc450 (talk) 17:56, 3 December 2014 (UTC)[reply]

Viscosity[edit]

Saying something is 100,000 times more viscous that water is a very poor explanation. Someone should change that (I can't) to state that "Basaltic lava has roughly the same viscosity as cold honey, and silicic lavas, like granite can be much thicker". —Preceding unsigned comment added by 169.233.42.202 (talk) 21:01, 15 March 2011 (UTC)[reply]

Something like that would be good, although it will need a source. Mikenorton (talk) 21:07, 15 March 2011 (UTC)[reply]

The section on Ultramafic Lava mentioning that lava at a temperature of 1600 °C can have a viscosity as low as that of water needs a citation. The other statements about viscosity like "100,000 times as viscous as water" could also be resolved by having tables or graphs with the viscosities of different lava types with respect to temperature. (Sciencebookworm (talk) 15:24, 1 August 2012 (UTC))[reply]

Source of heat and reason for melting[edit]

Geothermal energy was added as the source of the heat that liquifies the rock ... and yes gotta have hot. Variations in the geothermal gradient may be important (maybe for "hot spots" volcanism), but seems that decompression melting and addition of volatiles (as above a subduction zone) lowering the melting point temp are likely more important. Perhaps a section on this is needed? Vsmith (talk) 17:22, 20 June 2013 (UTC)[reply]

I agree. For instance, flux melting is extremely important in causing volcanoes associated with subduction zones. Attributing all melting to "geothermal energy" is misleading and does nothing to explain why volcanoes might occur in one place and not another. I suggest removing the line "The source of the heat that liquifies the rock within the earth is geothermal energy." and replacing with something like "Causes of melting vary by geologic/tectonic setting (see volcano)."Elriana (talk) 02:25, 21 June 2013 (UTC)[reply]

Komatiite viscosity[edit]

I added a "disputed-discuss" tag to the statement: "At this temperature there is no polymerization of the mineral compounds, creating a highly mobile liquid with viscosity as low as that of water." after User:Muymalestado added a source reference citation for this statement. My understanding is that the viscosity of water is about 0.001 Pa.s at 20°C. The cited source reference (Huppert, H. E.; Sparks, R.S.J. (1985). "Komatiites I: Eruption and Flow" (PDF). Journal of Petrology. 26: 694–725) states that the viscosity of komatiite is estimated to be between 0.1 and 10 Pa.s. (The paper quotes some experimental data points of 0.05 to 1.25 Pa.s at 1600 to 1800°C). This source reference article, which seems reliable to me, seems to contradict the claim in this Wikipedia article that komatiite lava had a "viscosity as low as that of water". I hope this contradiction can be resolved. Any comments? GeoWriter (talk) 13:02, 3 December 2016 (UTC)[reply]

Kilburn gives a komatiite viscosity of <1? Pa.s at an eruption temperature of >1600?°C on page 294 of Sigurdsson, H. et al. (editors) (2000) Encyclopedia of Volcanoes. GeoWriter (talk) 11:22, 15 October 2018 (UTC)[reply]

Semi-protected edit request on 6 February 2017[edit]

Please spell "immisible" with a c, as in "immiscible " 80.189.176.130 (talk) 17:31, 6 February 2017 (UTC)[reply]

 Done thanks for pointing that out - Arjayay (talk) 19:47, 6 February 2017 (UTC)[reply]

"ʻAʻā" listed at Redirects for discussion[edit]

An editor has identified a potential problem with the redirect ʻAʻā and has thus listed it for discussion. This discussion will occur at Wikipedia:Redirects for discussion/Log/2022 January 27#ʻAʻā until a consensus is reached, and readers of this page are welcome to contribute to the discussion. Jay (talk) 20:17, 27 January 2022 (UTC)[reply]