California's Supervolcano Nearly Erupted in 1982; The 3 Magmatic Intrusions

[@GeologyHub]

Note: This is a long comment answering every question you might have regarding today’s video, including some context. I recommending reading it all to understand what I’m saying and to not take my statements out of context. And no, this region of California (Mammoth Mountain, Mono Inyo, Mono Lake, and Long Valley Caldera) is not under any threat of a volcanic eruption anytime soon as of September 29th, 2023. I know that what I’m stating in today’s video might be considered controversial by some. Specifically that in 1982, the Long Valley Caldera (supervolcano) was at one point only 4 months away from erupting. But it of course did not erupt, with magma stalling at 4 km depth. My 4 month figure assumes that my interpretation of the maximum rate of magmatic uplift in 1982 was correct, when magma was at only 4 km depth. For a long time it was thought that this specific intrusion occurred beneath Mammoth Mountain and not Long Valley. I even stated as much in prior videos. However, much like on my opinion involving what caused the Younger Dryas, I looked further into various sources, and changed my opinion. (In the case of the younger dryas, I previously believed that a widespread airburst event caused it. However upon reading new evidence, the widespread burning the younger dryas experienced can be explained without an impact event occurring, so I am now of the opinion that the Younger Dryas was not caused by numerous meteorites exploding in airbursts). I do not simply change my opinion because a single scientific paper mentions something, as we scientists disagree on some topics all the time. However, in this case, after pondering long about this subject I came to the conclusion that the model of the 1981-1982 intrusion occurring within Long Valley and not Mammoth Mountain best fits the data recorded during that time and subsequent analysis. Q: So, am I of the opinion that a powerful eruption was 4 months away at the Long Valley Caldera? A: Absolutely not. While an eruption may have been as little as 4 months away, a large eruption in my opinion was simply improbable. If an eruption did hypothetically occur, it would have been of a small size in the opinion of GeologyHub. Maybe VEI 2-3. Q: If the magmatic intrusion did reach the surface, what do I think would have occurred? A: I would expect a small 150-300 foot high cinder cone to form in a mildly explosive VEI 2-3 eruption, perhaps covering an area of 1-2 km2 in a layer of basaltic lava. This is essentially what occurred 16,000 years ago during Long Valley Caldera’s last eruption. Although I have no direct proof of the intruding magma being basaltic, I made the assumption that it was basaltic based off of the Long Valley Caldera’s last several eruptions (the most recent of which was 16,000 years ago) producing basaltic lava. Some supervolcanoes erupt all the time, and the vast majority of these eruptions are not large. Take for example the Sakurajima volcano which is still erupting right now. It is part of the Aira Caldera supervolcano. Or, also in Japan, the Aso caldera has erupted more than 100 times in the last 500 years. None of these eruptions in the last 500 years were any larger than a VEI of 3. Q: Would you willingly live in the Long Valley Caldera, or in the town of Mammoth Lakes? A: Absolutely. In my opinion, what occurred in the 1980s was highly unusual, unlikely to repeat again in the next 100-200 years. I believe there is a low volcanic hazard, but it is low enough that in my opinion I’d feel safe living there. I’d even ski or hike parts of Mammoth Mountain. In fact, I hiked near the zone of tree kill in 2022. People generally love Mammoth Mountain, especially for winter sports activities like skiing and snowboarding. Q: Will any of the 3 intrusions that this video mentioned suddenly reactivate? A: In my opinion, 2 of the 3 will never reactivate. The only one which night is the 8 km depth intrusion which caused approximately 10 inches of uplift in 10 months in 1980. This marks the resurgent dome of the Long Valley Caldera (volcano), and such uplift events are likely quite frequent. Yet, magma will almost certainly not reach the surface in my opinion from this location for many hundreds, perhaps thousands of years. Instead, future eruptions within Long Valley caldera will likely occur at the edge of the caldera, as this represents a natural weak point. As for calling Long Valley a supervolcano, the U.S. Geological Survey calls this volcano as such at this link: www.usgs.gov/faqs/what-are-some-examples-supervolcanoes You might be wondering how I can say that the eruption hazard was overblown in 1982, while also at the same time stating that an eruption was as little as 4 months away. My response is that while an eruption was potentially months away if the magmatic intrusion continued its upward motion at a point in 1982, this was still months away from requiring any form of an evacuation. In other words, the tabloids jumped too far ahead of the logical time table progression involving the volcanic unrest in 1982. Areas aren’t simply evacuated because there is a magmatic intrusion. Evacuations generally only occur once it gets shallow enough to potentially produce an eruption. For example, the Mount Edgecumbe volcano in Alaska is still producing magmatic uplift due to an intrusion, but it is too deep at the present to cause an eruption, therefor an eruption of Sitka is not currently required (as of as of (September 29th 2023). The same was the case in 1982 at the Long Valley Caldera. If the intrusion had instead hypothetically continued upwards for a few more months, reaching shallower than 2,000 meters depth, then some but not all of the tabloids claims might not have been outlandish. Also, in the hypothetical event an eruption did occur in 1982, it would not have destroyed the town of Mammoth Lakes, as lava flows would have been directed away from the town, towards the east. The uplift center was simply in the wrong location for lava to flow towards Mammoth Lakes during such an event. As a final note, I will admit that the prospect of Long Valley producing an 8 km->4 km magmatic intrusion was quite strange and presents a potential problem for an assertion I made in today’s video. Typically, a portion of a magma chamber needs to be >=35% melt for a volcano to even be theoretically capable of producing an eruption. For context, the Long Valley Caldera maximizes out at 27% melt [Source G]. So, an eruption shouldn’t have even been possible to the first place. Therefor, one of the following things must be true: A: We have underestimated the maximum melt percentage in Long Valley’s underlying magma chamber. B: It is possible that a maximum melt % does not prevent a magmatic intrusion from occurring. Instead, it might simply prevent a magmatic intrusion if one does occur from erupting due to some mechanism which is not yet understood. In other words, the 1981-1982 magmatic intrusion may have been doomed to fail from day 1. C: We might be incorrectly assuming the minimum melt % a portion of a magma body must reach for an eruption to be theoretically possible. Perhaps the value is lower than 35%? Yes, this comment is actually longer than the words I said in today’s video. But hey, I had a lot to say! [Source G] Ashton F. Flinders, David R. Shelly, Philip B. Dawson, David P. Hill, Barbara Tripoli, Yang Shen; Seismic evidence for significant melt beneath the Long Valley Caldera, California, USA. Geology 2018;; 46 (9): 799-802. doi: doi.org/10.1130/G45094.1

[@LifeDrain1001]

Stopping kids from saying first on this comment

[@Vesuviusisking]

Do you think Yellowstone is overrated

[@ThatOpalGuy]

TL;DR... predicting anything regarding the earth is notoriously difficult.

[@GeologyHub]

@@Vesuviusisking Yellowstone is the best national park I have ever been to (in my opinion). So no, I do not think Yellowstone is overrated in that sense.

[@Vesuviusisking]

@@GeologyHub is Vesuvius overrated or underrated

[@SinnerChrono]

Its amazing how far our understanding of volcanology has changed in the last 40 years.

[@Gizathecat2]

I was living in Bakersfield in the 1980s. I remember all those earthquakes from Mammoth Lake/Long Valley. That is when I officially lost track of all the earthquakes I had experienced! It was like, “Every time Mammoth Lakes quakes, Bakersfield always shakes.”

[@joeofoysterbay7197]

I used to live in the mountains north of Fresno in the 80's and 90's and we too got a lot of Mammoth Lakes action. When that happened several hot springs in the region warmed up a bit too. It's a crazy and awesome state.

[@mistysowards7365]

Id's say everyone was a little jumpy in 1980s after St Helens massive eruption. Great video

[@GeologyHub]

This was definitely a huge factor. No one wanted another 1980 Mount Saint Helens repeat where the volcanic hazards were unknowingly (at the time) under warned.

[@baneverything5580]

@@GeologyHub Earthquake swarm is happening this morning at Mammoth Mountain.

[@felix-ve8jk]

As an East Coast transplant to California, the geology here is certainly not something I'm used to. I love Mammoth and it's very interesting to hear about the history of volcanic and seismic activity in the area. This is such a funny and interesting story.

[@TheSpaceEnthusiast-vl6wx]

Thanks, Geology Hub! This event is a great reminder that most magmatic intrusions fail and never see the light of day. We all know this, but large caldera systems (commonly called supervolcanoes) do not always erupt in VEI 7, 8 or possibly even 9 eruptions. The Mono Inyo craters has one particular eruption that seems to be related to one of the 535-536 mystery eruptions, via cryptotephras... Aleral Wei's Wikipedia edits brought this 5o my mind. Sorry for this, but I misspelled "Thanks" as "Thanos"!

[@Vesuviusisking]

People think it was Krakatoa

[@TheSpaceEnthusiast-vl6wx]

@alexdurn9465 It should be noted that sediment drilling in the Sunda Strait does not show much evidence of Krakatoa erupting during the time period of 535 CE. I think the eruption that created Krakatoa's original caldera is another mystery eruption, however.

[@floffycatto6475]

1:25 this shot of Twin Lakes brings back so many good memories

[@RoseNZieg]

I don't understand people. in terms of volcano activities, imminent doesn't mean it will happen. an eruption is the end result of several chains of events. if the volcano stalled at the last moment for whatever reason, then no matter how ready the volcano is, there's no eruption. there is a need to be vigilant and be prepared. panicking is not the proper action.

[@marktwain368]

Knowledge defeats ignorance and therefore abates fear.

[@Vesuviusisking]

@@marktwain368then why do people live in Naples Italy

[@juliefore]

IDK. For non-volcano related events, the word “imminent” tends to mean happening very soon. Very soon, in human timescales. As opposed to very soon in volcanic timescales.

[@lh3540]

This was way before the Internet too. We lived in the general area around that time and still had party line telephones.

[@GardenerEarthGuy]

I lived near Lassen and used to swim in hot creeks- one day swimming there was a rumbler quake and we ran out of the creek. A few minutes later boiling water came flowing down the creek...

[@Vesuviusisking]

Is that lassen peak

[@WestOfEarth]

😯

[@GardenerEarthGuy]

@@Vesuviusisking Mt Lassen

[@dougc190]

​@@Vesuviusiskingit's the general area but yes

[@GamerChick5567]

Oh wow! Luckily you didn't get burned. I stepped in a bad spot under the mud in Hot Creek near mammoth and basically jumped back to the shore. No damage but ow that was hot! 😅😅😂

[@chrisbrown1462]

Was in Mammoth while this was happening (1982) - I vividly remember the earthquakes and seeing all the trees flex. Quite an experiance. Used to camp all the time in the early 80s at Horseshoe Lake - pretty much right where the die off is. Definitely created in interest in all things geologic for me.

[@joeofoysterbay7197]

How did I never notice that the Mono Lake islands were lined up with Mammoth? I've spent a lot of time there and it's awesome. Good info!

[@Dragrath1]

Yeah the volcanoes are all aligned with Each other along with the whole Walker lane fault zone out there. Its the boundary between North America and the Sierra Nevada Great Valley block/microplate which is in the process of getting torn(or rather sheared) off the continent on geological timescales due to the relative motion of the Pacific and North America respectively

[@confuseatronica]

i was there at Rock Creek with my parents when the earthquakes happened. Much running out of buildings, getting covered with snow falling from trees etc.

[@yomogami4561]

thanks for the information interesting fact in the early 80s a road named the 'mammoth escape route' was built but local businesses and land owners complained so it was renamed the 'mammoth scenic loop'

[@marktwain368]

Isn't that nuts??! Watch the signs go up saying 'escape route' once the magma breaks the surface!

[@yomogami4561]

@@marktwain368 economy is more important then public safety in the u.s.

[@supertoasting1011]

I've seen your videos on the Azores, but would you please do a video covering the 1957-1958 eruption of Capelinhos on Faial specifically?

[@Jefuslives]

I remember this. The memory of St Helens was still fresh, and people were ripe for a scare. Shame on the tabloid media!

[@kennethblain610]

Thanks for your interesting and informative videos!

[@bevinboulder5039]

Mammoth Mountain looks to me like it had a lateral eruption sort of like Mt. St. Helens sometime in the past.

[@GeologyHub]

Mammoth Mountain may have produced pelean eruptions during its formation, or large merapi type vulcanian eruptions.

[@bevinboulder5039]

Interesting.@@GeologyHub

[@kevins8434]

Awesome content/awesome channel. Keep up the good work!!

[@Vesuviusisking]

Long valley caldera is underrated

[@psalmerperena4120]

That and also Valles caldera in New Mexico.

[@ShadyGrove83]

@@psalmerperena4120Valles was quietly updated to dormant from extinct status on the USGS website within the last 3-4 years, not sure when but I know it was listed as extinct there a few years back

[@sifarren]

I have 2 questions. 1st, the recent Swarm of activity off the coast of Western Portugal, near the Azores. Is this , now we've moved into the 5.0 magnitude, of concern and is this tectonic or volcanic in origin? I also wonder about the recent activity off vancouver Island in Western Canada, mid 4.pointers and then off the coast of northern California, on what appears to be the same fault line.. is this pressure releasing or something building up? . I absolutely love your channel, I'm learning so much . I check The volcano discovery app about 5 times a day, and my main regret in life is not being a Geologist.

[@GeologyHub]

Are you referring to the activity far offshore of Faial? That is merely tectonic.

[@sifarren]

@@GeologyHub thank you 😊

[@Velereonics]

One of the vents is like literally in middle of the slopes and they just casually say to avoid it sure I can but not everyone there is a good skiier, some dont have brains that function through the weed, and whiteouts sometimes make traversing around very confusing.

[@marypatten9655]

Thank you for sharing. After Mt St Helen erupted back in the 1980's. When the USGS gives a warning it us good to pay attention and stay praying. God bless

[@ginnrollins211]

Wasn't this referenced in the movie Dante's Peak?

[@GeologyHub]

I believe it was, although this might come as a shock but despite being a volcanologist I’ve never actually watched the film.

[@sirmonkey1985]

@@GeologyHub you should, it's pretty hilarious.. basically take everything you know could happen leading up to an eruption and multiply it by 100. definitely better and at least believable compared to the 1997 movie Volcano.

[@marktwain368]

It is vital that this channel continues its vigilance regarding continental volcanics; we all sense something is going to happen soon but a little Science helps allay the anxiety that percolates just beneath the social awareness managed by social media.

[@borismedved835]

"We all".... Good one! KZbin humor. A tiny proportion of people have been scared into that goofy fear, and of course they can be and have been tormented by the youtube pretenders who tweak their manipulable imagination.

[@humgum-w2x]

@GeologyHub like @sifarren asked about in their 2nd question are the quakes in Vancouver island and off the coast (since they appear to be on the same fault) releasing pressure or is something building up? be honest

[@sirmonkey1985]

hard to say but typically watching whats happening along on the major faults can sort of give you an idea of whats happening.. but it's also not unusual to see activity increase on a major fault after a large earthquake happens even it didn't happen in relation to it. everything is interconnected and also why they're able to map the interior of the planet by listening to seismic waves traveling from one side of the planet to the other.

[@jhill4874]

I remember this. It was used, in part, in the movie "Dante's Peak"...

[@Dogedart67]

Are you Kipp from Napoleon Dynamite? Love your online/chatroom status and technology!

[@Shivaho]

Some of my favorite hot springs ♨️ are in that area!

[@filipesiegrist]

Great List of volcanoes yet to cover: - Semeru - Aconcagua (Extinct) - Trindade (maybe extinct) - Agung - Pico do Fogo

[@AngryGecko1010]

When was the last time Yellowstone was (hypothetically) close to erupting?

[@GeologyHub]

Hmm. I do not believe we have enough ability to detect past fully solidified near-ish magmatic intrusions which failed, if they exist at Yellowstone. So for now I’ll simply state the date of Yellowstone’s last eruption; 70,000 years ago.

[@borismedved835]

It spewed a little lava flow 70,000 years ago. Now the small amount of magma in the chamber is always scaring amusing eruption imaginings out of a few people when its continued cooling causes little earthquakes.

[@carauctiontalk]

I was in Mammoth when the two 6 earthquakes hit.

[@LindaMerchant-bq2hp]

Caltech said once magma runs under the Salton sea and under Santa Monica mountains

[@GeologyHub]

Under the Salton Sea, definitely. You can see proof of this via active fumaroles at the Salton Buttes volcano.

[@SoCalDude1793]

I love the Eastern Sierra!

[@ladybowens6378]

I didn’t know they had a volcano

[@Vesuviusisking]

They have 5 volcanoes

[@jokerace8227]

There are volcanoes from there down to the Mojave Desert. Some appear to behave similar to the Craters of the Moon basalt fissures in Idaho, just not as large in square miles. There are Volcanic areas around Las Vegas and in Northern Arizona as well.

[@marktwain368]

And now that you DO, what has changed for you? Keep meditating and all will be well.

[@GamerChick5567]

If you ever get the chance I recommend to go see Mount Lassen too, and like another commenter posted the volcanoes in the Mojave are very interesting if you ever get the chance to do the Mojave Road/Cima dome, and visit Amboy (closer to the colorado desert) as well.

[@Trainfan1055Janathan]

"While trees need carbon dioxide to survive, too much is lethal to them." Thanks for pointing this out. There are still people repeating the myth that "it's fine to release carbon dioxide into the atmosphere because the plants will just absorb it." Carbon dioxide to plants is like oxygen to humans. We can't live without it, but there's a certain percentage by which we can no longer safely inhale it.

[@paytonlott5183]

holy crap i just moved here

[@GeologyHub]

Don’t worry. A volcanic eruption in my opinion is not likely anytime soon at Mammoth Mountain or the Long Valley Caldera. Enjoy how beautiful the area is! (I’d willingly live there hypothetically, but haven’t yet decided where in the world I want to settle down). Essentially, you are safe there for now. What happened in the 1980s was in my opinion quite unusual and probably won’t happen again in my or your lifetime.

[@sirmonkey1985]

lucky, if i ever decide to go back to california, it's definitely going to be in either the mammoth area or around the siskiyou forest area.

[@LCNWA]

better to be safe than gone! As this along the ring of fire on the west side of the NA continent.

[@SkepticalRaptor]

I am watching this video in Mammoth Lakes, CA. The geology here is awesome.

[@williamevans6522]

Hot Creek, south of MammothLakes got hotter

[@jcim6438]

Thanks.

[@michaeldeierhoi4096]

"While trees need carbon dioxide to grow too much is lethal to them". Words that global warming deniers may want to pay attention to.

[@sw8741]

I guess you do not have a very scientific mind. Those vents are expelling huge amounts of CO2, 10's of thousand times more concentrated than any "AGW" prediction. 2 other things, you should consider banning volcanos since they emit huge amounts of CO2. Also, according to your high priest NASA, the planet today has had a 15% increase of vegetation over the last couple decades due to increased CO2 concentrations. Those poor plants were starving for food due to natural carbon sequestration over the millennia and are very happy to not be starving.

[@EperogiLimousine]

@@sw8741 idk where you’re getting that vegetation from. Bud stop trying to disprove a threat to humanity

[@TheDanEdwards]

​@@sw8741 You're swimming deep into the denier pool.

[@haven216]

@@sw8741 ​ You conveniently left out half of that article. "While rising carbon dioxide concentrations in the air can be beneficial for plants, it is also the chief culprit of climate change. The gas, which traps heat in Earth’s atmosphere, has been increasing since the industrial age due to the burning of oil, gas, coal and wood for energy and is continuing to reach concentrations not seen in at least 500,000 years. The impacts of climate change include global warming, rising sea levels, melting glaciers and sea ice as well as more severe weather events." The beneficial impacts of carbon dioxide on plants may also be limited, said co-author Dr. Philippe Ciais, associate director of the Laboratory of Climate and Environmental Sciences, Gif-suv-Yvette, France. “Studies have shown that plants acclimatize, or adjust, to rising carbon dioxide concentration and the fertilization effect diminishes over time.”

[@sw8741]

@@haven216 And you conveniently leave out water vapor is 95% of all greenhouse gasses. You also conveniently leave out the fact they do not know how water vapor affects warming, if it contributes 80, 60, or 40% to warming. That is a HUGE variable which means they have no freak'n clue about the climate. CO2 is less than 3% of all GHG of which only 12% is man made, 88% of all CO2 in the atmosphere is naturally occurring. BTW....how does Philippe Ciais account for the huge amounts of plants and vegetation on earth when the amounts of CO2 far exceeded anything we have today? I'd bet most reading this grew up in a time where AGW was taught from the cradle. That is all they have heard all their lives, 0 thought given as to what science actually is. You're taught theory is fact when it is not, its only an idea that has supporting evidence, evidence which can be proven wrong and over turned. That is actual science. So keep on drinking your kool aid since its all you ever heard. Your lifestyle will be greatly diminished during your whole life on the altar of environmentalism. Already happening here in California, a "leader in the green movement", people are fleeing it for a better life. Damned hippies!🤣🤣🤣

[@myevilplans]

So in effect, some magma moved, the mountain farted and people lost their sh#t...

[@borismedved835]

Remembering the news from that incident, it was a bit funner than that. Somebody was building a big hotel there. After they were scared away and abandoned their partially constructed building, they later found out the facts of the matter and made some amusing complaints. If you look up news from those days, there was a lot of stuff like that. I remember some fine jokes going around at the time.

[@misusedfilms69]

Come on Mammoth Lakes Mountain, quit with the forplay...

[@HAL-su8uc]

JEEEEZIZ! your voice is just HORENDOUS! PLEASE find someone-else to narrate your videos. (they are great!)

[@cyankirkpatrick5194]

So the movie Volcano was almost real🤯

[@sirmonkey1985]

heck no, the movies based on an eruption that happened in mexico in 1943(Paricutin Volcano) except they put it in LA.

[@cyankirkpatrick5194]

@@sirmonkey1985 thanks for the info.

[@JulesUS8386]

Yeah that was due to my husband and my honeymoon 🥰🔥

[@dreddykrugernew]

If your an observant person there will be a major eruption on the west coast of the US, but there are a lot of devasting things that will happen before then

[@jamesfowley4114]

Not first.

[@grassnothing1631]

Supervolcano

[@Vesuviusisking]

So underrated

[@EperogiLimousine]

And?

[@SoEz2Hack]

AI generated trash.

[@GamingCeo420]

Nothing of value would’ve been lost

[@joeofoysterbay7197]

Probably true since everything to the east all the way to Atlantic would be coved in ash as happened last time, MUCH bigger than St. Helens. Yeah, I'm willing to let the east go. No big.

[@EperogiLimousine]

He’s an anti Californian Texan who wants everyone to live in God country @@joeofoysterbay7197

[@LydsTherinNotamon]

Imagine drinking this much political Kool-aid