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I don't know much about volcanoes. Am I correct in thinking that even though Mauna Loa is the largest volcano on Earth, this eruption is not a global threat in

I don't know much about volcanoes. Am I correct in thinking that even though Mauna Loa is the largest volcano on Earth, this eruption is not a global threat in the same way that eruption of Yellowstone could be, since it doesn't tend to be explosive?

ddoolin 4y ago
It’s just the largest active volcano, not the largest period. Super volcanoes are certainly much larger.
- Tuna-Fish 4y ago
  No, they actually aren't. The heat flow that powers Yellowstone is roughly similar to the one that powers Mauna Loa. The difference is that Hawaii hotspot is constantly erupting, and has produced roughly 6000km^3 of new rock in the past 650 kyears, which is how long it is from a proper Yellowstone supereruption, while the Yellowstone hot spot just builds and builds material and heat, until it finally all goes off at once. This is what's believed to be the difference between supervolcanoes and normal ones. There has been volcanism on a much larger scale in the past (see: large igneous province), but they aren't really volcanoes in the sense we understand them, and are not related to supervolcanoes.
toddm 4y ago
You are correct. The volcanoes in the Hawaiian chain are so-called mafic volcanoes. In general, volcanoes are classified as silicic or mafic. The silicic ones contain more gas and tend to erupt explosively; the mafic ones, more lava floes. Compare Mauna Loa (mafic) to Mount St. Helens (silicic), the latter of which was far more explosive due to high silica content, which increases magma viscosity and acts as a trap for (superheated) water and other substances. I encourage you and others to use the excellent USGS resources, such as: https://volcanoes.usgs.gov/vsc/glossary/ https://volcanoes.usgs.gov/vsc/glossary/ https://www.usgs.gov/news/volcano-watch-why-are-mount-st-helens-eruptions-generally-more-explosive-those-kilauea https://www.usgs.gov/news/volcano-watch-why-are-mount-st-hel... I hold a M.A. in geology and am a licensed geoscientist-in-training in Texas.
- solardev 4y ago
  Out of curiosity, why is geology a MA?
  - toddm 4y ago
    Good question. It's specific in my case to the school/department that awarded it. When I earned my M.A. at the University of Texas at Austin in 1995, the M.A. was the option for coursework and original research in the form of a thesis. The M.S. was reserved for the coursework-only option (rarely awarded). In 1996 (I believe), the department changed the thesis-based Master's to an M.S. degree and did away with any no-thesis degrees higher than Bachelor's. This decision short-sells the awardee, unfortunately. In general, an M.S. in STEM fields indicates a coursework-only degree (typically 6 classes, no thesis or original research) and an M.A. indicates a more rigorous course of study and research. My Master's thesis, btw, is "Desorption of High Explosives from Soil: Thermodynamics and the Role of Soil Organic Carbon."
    - solardev 4y ago
      > In general, an M.S. in STEM fields indicates a coursework-only degree (typically 6 classes, no thesis or original research) and an M.A. indicates a more rigorous course of study and research. I did not know that. Thanks for the explanation!
      - treewalking 4y ago
        I don’t know that this is a reasonable generalization. Certainly in my CS department one could write a thesis to receive an MS, and no MAs were offered. Just one data point, from a very large state school; YMMV.
        toddm 4y ago
        You're correct, it's not a reasonable generalization. See my reply above. The essence of my answer is based on the way things were in my graduate programs at my university when I was in school there; and some observations from so-called terminal Master's degree programs.
bell-cot 4y ago
Short answer: Yes. Longer answer: Very occasionally, a Hawaii-type volcano has a major landslide, which can create a huge tsunami - https://en.wikipedia.org/wiki/Nu%CA%BBuanu_Slide https://en.wikipedia.org/wiki/Nu%CA%BBuanu_Slide
- _yb2s 4y ago
  Wow, I didn't know about that. A link to a model from that page suggests massive tsunami heights around the pacific, including 70m in southern california! Something of that size would be cataclysmic, and wipe out most populated areas around the pacific rim... probably not likely since it hasn't happened for a million years.
  - deleted 4y ago
    [deleted]
daedalus_f 4y ago
Not a vulcanologist but, the hawaiian volcanoes largely erupt low viscosity (low silica) basalt lavas. Consequently they are not generally explosive in the way volcanoes with higher viscosity lavas (higher silica content) like andesite or dacite are. They don’t produce ash in a way that could have a major effect on the global climate. Happy to be corrected by someone more in the know, but I think the main risk to the wider pacific would be a flank collapse and associated tsunami but the probabilities of this are very low. There is evidence of previous such events: https://en.m.wikipedia.org/wiki/Hilina_Slump https://en.m.wikipedia.org/wiki/Hilina_Slump
- Cupertino95014 4y ago
  When I was there in 1998, there was a little river of lava that reached the Pacific. You couldn't get anywhere near it, but you could see the steam rising up.
lapetitejort 4y ago
Since this question has been answered already, I will suggest a documentary I watched recently: Fire of Love. It uses footage filmed by a French vulcanologist couple in the 60s-90s to tell their story and how the study of volcanoes has saved lives (and taken, as you'll see in the documentary). It's currently streaming on Disney+ in the USA.

ddoolin 4y ago

It’s just the largest active volcano, not the largest period. Super volcanoes are certainly much larger.

Tuna-Fish 4y ago
No, they actually aren't. The heat flow that powers Yellowstone is roughly similar to the one that powers Mauna Loa. The difference is that Hawaii hotspot is constantly erupting, and has produced roughly 6000km^3 of new rock in the past 650 kyears, which is how long it is from a proper Yellowstone supereruption, while the Yellowstone hot spot just builds and builds material and heat, until it finally all goes off at once. This is what's believed to be the difference between supervolcanoes and normal ones. There has been volcanism on a much larger scale in the past (see: large igneous province), but they aren't really volcanoes in the sense we understand them, and are not related to supervolcanoes.

toddm 4y ago

You are correct. The volcanoes in the Hawaiian chain are so-called mafic volcanoes. In general, volcanoes are classified as silicic or mafic. The silicic ones contain more gas and tend to erupt explosively; the mafic ones, more lava floes. Compare Mauna Loa (mafic) to Mount St. Helens (silicic), the latter of which was far more explosive due to high silica content, which increases magma viscosity and acts as a trap for (superheated) water and other substances. I encourage you and others to use the excellent USGS resources, such as: https://volcanoes.usgs.gov/vsc/glossary/ https://volcanoes.usgs.gov/vsc/glossary/ https://www.usgs.gov/news/volcano-watch-why-are-mount-st-helens-eruptions-generally-more-explosive-those-kilauea https://www.usgs.gov/news/volcano-watch-why-are-mount-st-hel... I hold a M.A. in geology and am a licensed geoscientist-in-training in Texas.

solardev 4y ago
Out of curiosity, why is geology a MA?
- toddm 4y ago
  Good question. It's specific in my case to the school/department that awarded it. When I earned my M.A. at the University of Texas at Austin in 1995, the M.A. was the option for coursework and original research in the form of a thesis. The M.S. was reserved for the coursework-only option (rarely awarded). In 1996 (I believe), the department changed the thesis-based Master's to an M.S. degree and did away with any no-thesis degrees higher than Bachelor's. This decision short-sells the awardee, unfortunately. In general, an M.S. in STEM fields indicates a coursework-only degree (typically 6 classes, no thesis or original research) and an M.A. indicates a more rigorous course of study and research. My Master's thesis, btw, is "Desorption of High Explosives from Soil: Thermodynamics and the Role of Soil Organic Carbon."
  - solardev 4y ago
    > In general, an M.S. in STEM fields indicates a coursework-only degree (typically 6 classes, no thesis or original research) and an M.A. indicates a more rigorous course of study and research. I did not know that. Thanks for the explanation!
    - treewalking 4y ago
      I don’t know that this is a reasonable generalization. Certainly in my CS department one could write a thesis to receive an MS, and no MAs were offered. Just one data point, from a very large state school; YMMV.
      - toddm 4y ago
        You're correct, it's not a reasonable generalization. See my reply above. The essence of my answer is based on the way things were in my graduate programs at my university when I was in school there; and some observations from so-called terminal Master's degree programs.

bell-cot 4y ago

Short answer: Yes. Longer answer: Very occasionally, a Hawaii-type volcano has a major landslide, which can create a huge tsunami - https://en.wikipedia.org/wiki/Nu%CA%BBuanu_Slide https://en.wikipedia.org/wiki/Nu%CA%BBuanu_Slide

_yb2s 4y ago
Wow, I didn't know about that. A link to a model from that page suggests massive tsunami heights around the pacific, including 70m in southern california! Something of that size would be cataclysmic, and wipe out most populated areas around the pacific rim... probably not likely since it hasn't happened for a million years.
- deleted 4y ago
  [deleted]

daedalus_f 4y ago

Not a vulcanologist but, the hawaiian volcanoes largely erupt low viscosity (low silica) basalt lavas. Consequently they are not generally explosive in the way volcanoes with higher viscosity lavas (higher silica content) like andesite or dacite are. They don’t produce ash in a way that could have a major effect on the global climate. Happy to be corrected by someone more in the know, but I think the main risk to the wider pacific would be a flank collapse and associated tsunami but the probabilities of this are very low. There is evidence of previous such events: https://en.m.wikipedia.org/wiki/Hilina_Slump https://en.m.wikipedia.org/wiki/Hilina_Slump

Cupertino95014 4y ago
When I was there in 1998, there was a little river of lava that reached the Pacific. You couldn't get anywhere near it, but you could see the steam rising up.

lapetitejort 4y ago

Since this question has been answered already, I will suggest a documentary I watched recently: Fire of Love. It uses footage filmed by a French vulcanologist couple in the 60s-90s to tell their story and how the study of volcanoes has saved lives (and taken, as you'll see in the documentary). It's currently streaming on Disney+ in the USA.