Large magma bodies found beneath dormant volcanoes
32 comments
·February 10, 2025sigmoid10
snowwrestler
Active/dormant/extinct are not ternary since even “active” volcanoes don’t erupt all the time.
Active and extinct are more like endpoints with most volcanoes falling into some degree of dormancy, usually indexed by how long it has been since last eruption.
The surprising thing is there doesn’t seem to be correlation between time since last eruption, and size/shallowness of a magma chamber. That essentially removes one of the signals that vulcanologists were hoping would help inform predictions of the timing of the next eruption.
> I always thought dormant merely means asleep - as in not currently active, but may wake up at any time.
There is a lot of hope that dormant volcanoes don’t wake up at “any” time, but rather at predictable times. And the farther in advance we can make an accurate prediction, the better. So a lot of volcano research inclines toward “can this help us improve our predictions?”
echelon
This is pop-sci journalists once again ruining the message by either not understanding the paper or by dumbing it down to the point it becomes lazy and counter-factual. I think it's mostly the former, because there definitely exists a way to "explain it like I'm five" without telling mistruths.
This pop-sci garbage has me hardcore Gell-Mann amnesia-ing [1] the rest of the journalism industry.
godelski
> counter-factual
I bring this up because one common way a message is misinterpreted is that words are overloaded. So people read a thing, understand it with one definition of words, but the intended definition is different. Because knowledge is often passed through a game of telephone[1] context is often lost or degraded, making it harder to decode the intended meanings.
Probably worth mentioning that there is no lower bound in complexity for a lie, but the is for truth. Worse, no real "truth" exists, it is just ever approaching something that is "more correct" with exponentially increasing complexity.
I often wonder if we've just advanced so far that we can no longer make sense of things with first or second order approximations. That it's just so difficult to find sufficient approximations that we break down. Our desire to have answers is stronger than our desire to understand. I suspect this is a great filter if there are any. It makes sense for any evolved creature to hit this point, as we definitely know computational complexity increases dramatically with respect to higher order terms.
bell-cot
> ...the long-standing belief that active volcanoes have large magma bodies that are expelled during eruptions...
I'm not a geologist, and my current "knowledge" of volcanology is mostly from the GeologyHub YouTube channel - but that is completely contrary to my understanding. If a serious magma chamber is emptied during an eruption, then the volcano above it (and some of the surrounding area) will collapse into the empty chamber. Because there's no way in hell that an empty magma chamber could support the weight of its own roof.
The vast majority of volcanic eruptions - even VEI 5 ones, like Mount St. Helens in 1980 - do not work like that. The magma chamber is still there, after. It's probably shrunk a bit - volcanologists measure ground-level uplift and subsidence in centimeters, to monitor that - and is a bit depleted of volatiles (volcanic gasses, which can act a bit like the fizz in a shaken bottle of soda). That's it.
Gracana
The article follows the typical pop-sci presentation of "scientists are gobsmacked by thing that's obvious to laymen," but of course it's really not like that. This is the abstract of the paper:
Quantitative estimates of magma storage are fundamental to evaluating volcanic dynamics and hazards. Yet our understanding of subvolcanic magmatic plumbing systems and their variability remains limited. There is ongoing debate regarding the ephemerality of shallow magma storage and its volume relative to eruptive output, and so whether an upper-crustal magma body could be a sign of imminent eruption. Here we present seismic imaging of subvolcanic magmatic systems along the Cascade Range arc from systematically modelling the three-dimensional scattered wavefield of teleseismic body waves. This reveals compelling evidence of low-seismic-velocity bodies indicative of partial melt between 5 and 15 km depth beneath most Cascade Range volcanoes. The magma reservoirs beneath these volcanoes vary in depth, size and complexity, but upper-crustal magma bodies are widespread, irrespective of the eruptive flux or time since the last eruption of the associated volcano. This indicates that large volumes of melts can persist at shallow depth throughout eruption cycles beneath large volcanoes.
dang
Ok, we've taken surprised scientists out of the title above. Thanks!
bregma
It would probably benefit society as a whole if the abstracts of scientific papers (not their content) eschewed sesquipedalian loquaciousness.
Here's the same abstract for the more nearly human.
This paper presents evidence and analysis that shows large magma chambers can be found under all non-extinct volcanoes on the west coast of North America.krisoft
Idk. You can always just leave out details to make things simpler. I could rewrite your version of the abstract to "Scientist find magma under volcanoes." Much simpler! Leaves out a lot from yours, but so did yours leave out a lot from theirs.
I think in this case it is important to consider the audience one is writing to. And the abstract is written to other geologist. They want to know what kind of evidence they have (purely computational? new field measurements? what kind of modality?)
While for me this sentence[1] is hard to penetrate jargon, presumably for the intended audience it is packed full of information. Same as the sentence "we persist the setting in a local sqlite database using sqlalchemy ORM" means a lot more to some dev like me than "we save the setting". You can simplify it of course, but while you make it easier to understand to a lay audience it becomes less specific to the intended and specialist audience.
1: "seismic imaging of subvolcanic magmatic systems along the Cascade Range arc from systematically modelling the three-dimensional scattered wavefield of teleseismic body waves"
skytwosea
I disagree. This abstract is a mouthful, no doubt, but it's a highly information-dense mouthful, and it does its job well.
Along the spectrum between intra-disciplinary academic communication on one end and public-sphere science communication on the other, the abstract is and should be just above the level of the paper it's abstracting. It's meant to be a technical summary for academics, and should not be dialed down for the sake of non-technical consumption. This one - speaking as a geologist with a long academic history - reads quite well, I think.
In contrast, the sentence you propose should be the output of responsible and effective scientific communicators working closer to the public-sphere end of the spectrum, say, at the level of phys.org, here on hackernews, etc.
beowulfey
Many journals use a separate summary statement which describes the findings and significance in more ordinary terms (eLife is a good example). An abstract has a specific purpose and it is not quite meant for a public audience. It can also vary depending on the journal, with less specialized journals being written for broader audiences.
(Although I will agree this one is a bit unnecessarily verbose)
PaulHoule
That's squashing it too much. The angle that magma chambers could be diagnostic of eruption risk is what I think the public would find most interesting. The results seem to say that it isn't so.
stevage
Obviously that fails at actually being an abstract: it doesn't communicate what the novel research is, or anything about the methods.
Journals aren't for lay people. It's the pop science articles that should do better.
Also, honestly, this abstract was much more comprehensible than I expected.
gus_massa
That is what the press release from the university should have, but many of them add a lot of hype and distort the paper. Something like
fake> For fist time, scientists of $OUR_UNIVERSITY have seen Doors of Hell with their own eyes and are going to use it to replace Nuclear Power in 5 years and solve Climate Change and find the Atlantis.
I'm exaggeration a little, but I've seen a few horrible cases https://hn.algolia.com/?dateRange=all&page=0&prefix=false&qu...
exe34
I wish they would have both. Personally when I'm reading something in my field, I want the specific details, but when I'm reading outside my field, I could use the dumbed down version.
matthewdgreen
What sort of evidence and analysis? Did the scientists dig a tunnel underneath these volcanos and drop a dipstick? Point being that the “loquacious” information you removed from the summary contained useful information and your summary just tosses it.
mannykannot
Indeed - at no point does the article quote a geologist expressing surprise at the result. There are quotes saying, in effect, that new data overthrows or requires modification of a previously-held conjecture, but that is not the same as surprise. Experts in a given field are usually well aware of how conjectural a hypothesis is, as that is where current research is focused.
lupusreal
Echoing what other commenters have said, I can't square the supposedly surprised scientists with what I thought I already knew about volcanoes. Can anybody figure out where the miscommunication occurred?
Matching my layman understanding, Wikipedia says that an extinct volcano is one that no longer has a magma supply, but that dormant ones may unexpectedly become active. The article on the other hand speaks of dormant volcanoes supposedly being understood to have "empty" magma chambers, which structurally makes no sense, and should very clearly differentiate them from active volcanoes. Wikipedia says that the demarcation between dormant and active is so wishy washy that the term dormant is basically obsolete in the scientific literature. So what gives?
mapt
I suspect it has something to do with the concept "magma chamber", as if there is a big, singular hole underneath each volcano, rather than a loose network of multiple layers of melted & semi-melted rock spread over tens of kilometers of crust depth, organized by geological strata, which periodically melts through an obstruction or solidifies into an obstruction.
irrational
Scientists keep talking about the three sisters rising, so clearly there is action happening there. And St Helens keeps erupting, says clearly there is action happening there. It doesn’t seem surprising that the other volcanoes in the area could also be potentially active.
tehwebguy
Likely place for them to be
metalman
the amount of data concerning the earths internal structure is growing in leaps and bounds. The ability to discern between rock types, water, oil, gas, faults and fractures, and molten and semi molten rocks is becoming much more precise. The fun part is that siesmologists use the earths own movements and resulting siesmic and acoustical waves to build the picture, though the scale is intimidating, beyond human capacity to know in any fine detail.Add in ground penetrating radar and experiments useing known explosive charges, placed in precise locations, and the fine resolution just gets better. Bet the whole geology field is having fun.
null
komfuuuu
[flagged]
>The team found that all of the volcanoes, including dormant ones, have persistent and large magma bodies.
I always thought dormant merely means asleep - as in not currently active, but may wake up at any time. This is different from extinct volcanoes, which would actually be expected not to erupt. Crater lake in particular has well established hydrothermal activity, which strongly suggests there is still something going on below and it may erupt again in the future. Any geologists can explain what the surprising thing here is besides the apparent difficulty to distinguish dormant and extinct?