The VC Bar

Welcome to the Volcano Café bar, a place for all things on or off topic and inane ramblings. There has been a need of late to find a place better suited to various theories, long comments and enthusiasm. This page will be less moderated than the main article pages and cleared out every month (this may change depending on use).

Have fun and don’t forget to tip the barman 😉

1,338 thoughts on “The VC Bar

  1. Question for Albert and Dust Devil

    Halemaumau and Nyiragongo lava lakes are about the same size.

    But why haves Nyiragongo so many many more smaller crustal plates than halemaumau had?

    Nyiragongo can have 30 to 50 small crustal plates on its lava lake!
    Halemaumau 2008 – 2018 only had 4 to 8 large plates on Its lava lake when it was not disturbed.

    Nyiragongo lava lake haves faster lava lake circulation? explaining the smaller and more numerous lava lake crust plates?

    • That is an excellent question. It is similar to pancake ice formation. The pancakes grow in size over time. The growth rate is limited by the temperature of water and air, and by the roughness of the water and the tensile strength of the ice, but eventually they merge and form a single ice sheet. Lava floes are a bit different but act in the same way. The size will be determined by the rate at which surface lava solidifies, the roughness of the surface, tensile strength (composition) and (and this is different from ice) how quickly the solidified floes sink again. The roughness will be mainly determined by how much degassing there is. The rate at which floes form depend on lava temperatures and composition, and turn-over rate of the lava lake.

      • Nyiragongo and Halemaumau lakes where / are the same size

        But Nyiragongo haves far more crustal plates
        Nyiragongo is much much more broken up.
        Halemaumau much larger plates, but just as thin crust.

        Nyiragongo haves a diffrent mineralogy and composition. And probaly ( faster lake convection ? )

        • If you can find time-lapse movies of both lakes, try to estimate how quickly these floes grew and how long each one lasts on average.

          • looking for it

            These two lava lakes are driven by same laws
            But appears radicaly diffrent in number of crust – plates

          • Albert watch the videos and have your own opinion : )

            Nyiragongo is unique its the only active Nephelinite lava lake and Nephelinite volcano on the planet.

            Maybe its time for a VC Nyiragongo post soon? About Nyiragongos hazards, its volcanological and morphological evolution and eruptive styles and scenarios and potential future evolution of the arera and the geology of the volcano.

            This volcano is very unusual

          • The Nyiragongo video has no indication of elapsed time, so it is not possible to judge the speed. But there are interesting differences. The Halemaumau video shows how the floes form by spreading from the centre, and drift fairly rapidly to the edge where they get sucked down. The size is already set at rifting and does not change. The Nyiragongo floes form very as very small floes in the centre. Movement is not so clear but floes at the edge of the crater are much larger. It seems to me they may live longer than the the Halemaumau floes and grow over time. The floe size at formation depends on the tensile strength of the solidified lava and the turbulence. The central turbulence is much more pronounced in Nyiragongo, so only small floes can form (larger ones would break). The Nyiragongo lake may be hotter and(or) more gas rich.

          • Photo from Nyiragongo
            Nyiragongos crustal plates are indeed very small … these at the edge are less than 10 m across since the lake is 260 m wide…

            Tension strenght at the skinn maybe a factor… but it must also be rather hot.. maybe halemaumaus plates are more flexible than Nyiragongos

            I think Nyiragongo s convection is faster… because when halemaumau lava lake was disturbed by rockfalls it became just as churned up and fragmented as Nyiragongos surface.

          • Halemaumau was extremely gas rich.. the lava under the glass skinn on the overlook lake was a superfluid superhot gas foam
            Remeber halemaumaus enormous sulfur gas emissions when it was going 2008 – 2018. Mostly sulfur and co2

            Nyiragongo is a competely diffrent magma and composition
            Superalkaline magmas like Nephelinites tends to be richer in water vapour and loots of Carbon Dioxide specialy from Nyiragongo.

            There are no clear data on Nyiragongo lava lake temperature
            But Patrick Marcel measured over 1200 C in the lake.. if the readings where correct

          • This is a rather intresting photo of Nyiragongos lava bubbling under full daylight.
            Lots of magmatic water vapour ( steam condensation ) and a rather very dull red in daylight. This coud indicate that Nyiragongo is acually cooler than Kilaueas thoelitic basalts. That makes sense because partial melting that forms Nyiragongos magmas are very small in ammounts compared to basalt mantle melting.

            Two studies suggest that these says below 1000 C : https://www.sciencedirect.com/science/article/pii/S0012821X18304631

            https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2013JB010520

            But Patrick Marcel directly measured the lava lake in 2017 when Nyiragongos lake was in high stand: there he found well above 1200 C ( 1250 C ) maybe a more accurate description to explain the fludity of Nyiragongo.

            But the dull red colour in daylight says other thing..

          • The temperature has been measured at 600-1250 K. That is quite a range, but note that the surface temperature is mainly that of the solid floes and those are surprisingly cool (rock insulates very well and the floes can cool down especially if quite long-lived, as seems to be the case). The low range corresponds to those rocks. The high end corresponds to where the fresh lava breaks through. Also note that the measurements are often quoted in Kelvin (as is the case here), not Celsius. The different measurements of the fresh lava seem to be quite consistent, 1100-1250 K (850-1000 C). So, as you point out, does the colour. Marcel seems to be the outlier but I don’t know what he measured. The magma temperature is considerably higher, of course.

          • Albert this video made my Patrick Marcel shows very much how very fluid Nyiragongo is!

            Notice the lava bubble bursts in the middle of the lava lake at 0:37
            Burst the surface like water bubbles.

            The 1250 C temperatures are probaly correct as he measured under the lava lake skinn when the lake was very high 2 years ago.

            This coud be the sillicate lava with the lowest viscosity

            https://m.youtube.com/watch?v=VvQKCX3L-44

          • Indeed lava lake crust is an amazing insulator.
            Halemaumau and Nyiragongo crust are milimeters thick maybe a centimeter. Yet these black crust plates may only be 200 C. Halemaumau had spots down to 150 C so its very insulating.

            Patrick Marcel measured under the lava lake crust. In 2017 the lava lake was just at crater floor level.. that made it easy to walk to it and push down instruments ( in thermal suit and thick gloves )
            The lava lake crust insulates and the heat is not insane close to the lake if its calm.

            Marcel measured 1250 C quite similar to halemaumau temperatures.

            Durieux samples 2003 found pure glass melt from Nyiragongo lava lake. All crystal phases where molten. Suggesting 1200 C coud be the magma temperature.
            But Nyiragongo is diffrent minerals too from normal thoelitic basalt…

            The daylight photos makes me doubt these temperatures

            But the lava is so very very fluid
            So it must be rather hot?
            I know the sillica is very low too ( 36% )

          • https://m.youtube.com/watch?v=uJsUbqovR0c

            Albert this is a fun video!
            Throwing gas cans in Nyiragongos lava lake. Just for fun they did it.
            Marcel had loots of fun there.

            Notice how the cans cannot penerate the crust…
            Lava is a very high density fluid even if Nyiragongo haves very low viscosity

          • Another good one of Nyiragongo lake bubbling in direct daylight…
            This sillicate lava ( Nephelinite )
            is extremely fluid
            But I dont know if its as hot as Iceland and Hawaiis Thoelitic Basalts..

            Nyiragongo is far smaller partial melting rates in mantle

          • In this Nyiragongo photo in direct daylight the bubbling lava appears to almost not glow at all….

          • Albert these daytime photos of Nyiragongos lava lake may suggest that the lava is a bit cooler than normal basalts ?

          • Albert: I think Kilauea is hotter than Nyiragongo. This is a photo during daylight and its bright orange.
            Nyiragongo is very dark dull red in daylight.

            Kilauea in this photo.. is bright orange in daylight. Maybe it makes sense with Hawaii and Icelands Thoelitic Basalts are hotter because they are products of far more partial melting in the mantle.

          • Hey Jesper,

            What about Erta Ale? I mean like Nyiragongo, it’s lavas tend to form a shiny-ish solidified crust within seconds of exposure to air..

          • All lava lakes forms a shiney glass crust when its exposed to the much colder atmosphere

            Specialy these lava lakes with a calm surface.

            Erta Ale is a Thoelitic Basalt quite similar to Iceland and Hawaii in composition. The Afar Plume haves large ammounts of partial melting.

            Erta Ale and Nyiragongo is very diffrent in composition in magma.

            Nyiragongos lava lake is of course much much larger than any of Erta Ales recent lava lake / lakes

  2. Always so many crustal plates on Nyiragongos lava lake
    The convection is probaly faster than halemaumau and it ( may be more fluid too )

    Nyiragongo 2011

  3. M 3.5 earthquake below Pahala, Hawaii.

    M 3.5 – 5km NE of Pahala, Hawaii – 35.2 km deep – 2020-01-06 21:19:02 UTC

    • Another star at Pahala yesterday:

      M 3.1 – 7km E of Pahala, Hawaii – 36.05 km deep – 2020-01-09 00:26:58 UTC

    • And another earthquake reviewed to M3 in the Pahala swarm:

      M 3.0 – 7km ENE of Pahala, Hawaii – 34.05 km deep – 2020-01-10 04:19:34 UTC

      • Kilauea is showing off including a 2.4 and 2.7 around 1/2 hour apart. The tilt readings are a e weird but there is snow on Mauna Loa, and rain around Kilauea. Some of the instruments might show some possible tremor, but they are such a mess with the rain??
        2020-01-12 16:03:06 1.9 -1.1
        2020-01-12 14:21:28 2 -1.1
        2020-01-12 14:20:45 1.9 0.2
        2020-01-12 12:56:51 2.7 -0.2
        2020-01-12 12:16:27 2.4 1
        2020-01-12 07:46:29 2.1 0.2

        • The Mauna Loa tilt showed a strange excursion and went off line. I did not know why but snow is a likely explanation!

  4. Albert maybe its time for a VC Nyiragongo post soon? About Nyiragongos hazards, its volcanological and morphological evolution and eruptive behaviour and scenarios and potential future evolution of the arera and the geology and mineralogy of this volcano.
    The volcano is only 20 000 years old.
    2 million persons now live under Nyiragongos threat

    This volcano is very unusual, unique infact by volcanoes on Earth. Its magmas haves No other terestrial analouge in the solar system and is the only active Nephelinite volcano on planet Earth

  5. On 9/01/20 Dellenite wrote:

    No one can do science and at the same time have an agenda, pick one or do neither. Anyone who argues for AGW should be open to facts that prove otherwise and anyone who argues against AGW should be open to facts that prove it is so.

    Tell that to a climate science denier. The error in that observation lies in the assumption that climate science deniers are interested in science. They are not and reasoned presentation of overwhelming evidence does not work. The agenda of most climate science deniers is the 3 Ps – Politics, Power and Profit. The trick to winning a debate under these rules is to play the same game.

    I have tested a theory that has worked for me on the occasions I have needed to employ it. When reasoned presentation of the evidence fails to persuade an intransigent and demonstrably erroneous view, inflict increasing amounts of pain until succumbing to reason is the preferred outcome. It is a mode of dialogue even politicians understand.

    • Global warming is 100% proven to be caused by humans

      The rise in CO2 is extremely rapid during 1900 s and 2000 s and it first began rising in 1800 s as industrial age began.
      We humans release close to 50 gigatons every year!

      In 2010 s we began to choke the atmosphere rising to over 400 ppm and its rising at many PPM every year now

  6. IMO: Due to technical issues earthquake activity does not appear on our website. Repairs are in progress. The earthquake activity is monitored 24/7 at the IMO and if earthquake activity increases somewhere while repairs are still in progress, comments will be posted about it here.

    • Yes, this has gotten very silly. Someone started out putting press releases about these ‘supermoons’. It is only a matter of time before they will be just to announce a full moon! The naming of full moons comes from New England and probably should stay there. I find the ‘blue moon’ more interesting because of its history of failure and misinterpretation. Even google, when you ‘once in a blue moon’ in the search bar gets the number slightly wrong. (Unless they now quote my number in which case they are spot on.) And a few years ago we had an eclipse during a blue moon, so the moon was blue and red at the same time. Now that was worthy of a press release.

      And on topical news, militaries across the world have yet to try to shoot down the moon. But there has been a case when a missile was launched at Venus, when it was mistaken for a threat. It missed. I won’t mention the aborted attempt to shoot down the space shuttle.

    • Indeed a 17 km tall and 240 km wide behemoth of a volcano. All other non Hawaii volcanoes are really small in comparsion.
      Most of Mauna Loa ( 90% ) is less than 200 000 years old. With oldest parts around 400 000 years old.
      An enormous ammount of materials in souch short geolgical blip time

    • Mauna Loa coud probaly produce many 1000 s of km3 of Thoeltic Basalt before fully going postshield as it loses the Hotspot to the next giants to become: Kilauea and Loihi

    • Knowing that Kilaueas east rift zone is acually longer than Mauna Loas rifts …

      Its a sign that Kilauea will grow into a monster in the future .. larger than Mauna Loa is today

    • That is… very intriguing.

      Maybe there is a deep crustal magma chamber all the volcanoes are connected to. The Altiplano Puna Magma Body contains 500000 km³, so they can get very big. Usually they are shaped like a sill so the can cover an enourmous area.

    • Holy crap 500000 km³! thats 5 Mauna Loa volumes of Ryholite magma!

      And its sill shaped too? not pluton shaped?
      Is this not a molten yet to become batholith?

      • And the Sierra Madre Occidental flare-up had a magma chamber that if I remember right would have completely dwarfed the AP Magma Body. These are very thick sills however, don’t know how much exactly.

        • Unfortunately there isn’t a lot of study dedicated to this area. So I can’t really make out the form of the magma body. It could be previously undiscovered hotspot or a poorly constrained body.

  7. I just upgraded to the new Microsoft edge. Works nice. Might be a coincidence, many of the seismograph stations on the big Island are now showing data that I have not been able to see in maybe a year or more.

      • HSSD, PLAD, ALEP, MLOD, KLUD, KIND…….there are more. I have a slow internet connection, only around 6mbs with a lot of lag. I sometimes think that the requests (for DATA) time out since it takes too long for my system to get and receive data. I had major problems with the old edge. I use Weather Underground for watching the weather and I could not use it on Edge, had to have a different browser for it. The new Edge is faster than any of the other browsers I use regularly (Chrome, Opera) and is based on Chrome.

        • I have always been able to see those stations, or at least a couple of those. Seems you’re right.

    • I’ve been using the Edge Beta based on Chrome for a while. All the Java and other scripting functions work where the useless old Edge browser did not.

  8. Hawaii deep tremor. Looks like from Pahala, given that it has the typical shape they come us and also that there are rarely any other sources of deep tremor in Hawaii.

    06:57-07:25 UTC, not located by HVO

    • DD
      Did you notice that the event at 6:36 UTC is not reported. I looked at TOUO and was wondering about the shape of the event at 8:47 (2020-01-17 08:47:35 2.4 33.4) looks a little fat to me.

      • If you go to the past week map for Kilauea there is a green M2 under the summit that looks like it matches in time with the 6:36, it could be that one. It sometimes pisses me off that HVO doesn’t report a large portion of the earthquakes, it is mostly small events that do not make it into the USGS catalogue but I once saw an M3 being left out… I am not sure how it works or why they do so, guess there must be some reason?

        Hmm… the 8:47 is very weird when compared to other Pahala earthquakes, it may be interesting, so later I will look at the frequencies and see if I can find something out.

        • I think that it is some part of their automation for collecting the data and then processing it. They let us see the raw data coming from the instruments, but they have to filter out the small quakes, bad data, known issues, interference or equipment problems transmitting the data, all in near real time. Showing up for work and finding these issues is Job security for them (actually the science is), not catering to us VolcanoCafe geeks that are looking at a 2.1? quake in the middle of their night.

          Mac

          • Weird though for HVO to filter out so many M2-M0 events, IMO wouldn’t do that, nor do other observatories in the mainland Unites States (as far as I know).

            It is a small percentage of what they are actually capable of locating that it is later reported

      • There is definitely something that follows the 08:47 event and it shouldn’t. However the earthquake and the following burp have the same frequency so idk.

  9. Carl
    It has been several days since we thought Snow or weather might have impacted the Tilt on Mauna Loa. I noticed today that even if the little snow left, or cold temps, the tilt is still continuing on the same trend. I also noticed that the week tilt is measuring about 1 microrad of difference between 0 and 90 deg, but the month map shows around 4 microrads of difference. Some of the GPS stations are showing some change, not sure how that might affect

    Any suggestion on a reason the month and week would show such a difference, or would you still think instrumentation issues from cold or recent movement at the summit?

  10. https://www.youtube.com/watch?v=eQ-JKf-iQpg
    This is a very good video, showing just how extremely fluid Hawaiian lavas are

    I dont know any other sillicate lava other than Nyiragongo… that is as fluid as this…

    I haves a question: both Halemaumau and Holuhraun had a similar temperature and sillica content,
    But why was Holhuraun ( somewhat more viscous than halemaumau ? )
    Despite same temperature and sillica content…?

    • Albert! any idea why Holhuraun was more viscous than Halemaumau? despite both having similar sillica content and temperature.

      mysterious

        • Hmmm but it emerged with similar temperatures and sillica content as Halemaumau….Thats around 1200 C.
          Holhuraun emerged at almost 1200 C

          Im very confused.. both had same temperature and sillica.

          But Holhuraun was an extremely fluid eruption too…

          Did you knew that Holhuraun was the most fluid and hottest eruption so far in Iceland.. that was captured on camera

        • When it breached the ground in Holuhraun… it was same temperature and sillica content as Kilaueas summit.

          Yet … Holhuraun was ( somewhat? ) more viscous
          Still it was a very very fluid eruption

  11. Hilarious. Dogs will tend to get excited and dart back to the house when they get done doing whatever. Pekinese just finished his task and darted back to the house… right into a chair.

    So… Jake (“Big Dog”) is not the only doofas in my pack.😄

  12. An interesting change at Mauna Loa. The tilt measurements show a pronounced diurnal change, tilting when heated by the sun. Only the green line tended to show this. When this daily change stops, you know the weather isn’t as good – cloudy or snowy. But now, the blue line (at a 90 degrees angle from the green line) also shows it. I have no idea why this change happened. I assumed it was electronic but it didn’t go away.. The shape of the diurnal variation of the green line has also changed: it it is now quite asymmetric. It is almost as of the instrument was rotated by 45 degrees but that is rather unlikely. There has been a change in the calibration. The snow earlier in the month introduced an offset, and this has been kept in the plot even after it stopped snowing. That should go away after Feb 12 when the snowy time rolls of the end of the plot. But that should not affect the response to ground temperature.

    • Depth not reported yet (10 km means : not known). And this may be close to Lebanon, it is not a remote area. Malatya has a population of around a million.

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