Why are Three Fingered Jack etc. Volcanoes considered Extinct? Remember 4 peaked in Alaska was Extinct yet it erupted in 2006. Could you explain further about Extinct Volcanoes? Thank you
I think the only ones that can be conclusively ruled out as extinct are the ones that have long been cut off from any potential magma source, although the longer since the last eruption the less likely any renewed activity is. Hard to draw a firm line on how long time is enough to be designated as extinct since many types of volcanoes work on entirely different timescales.
Geologic time is so much bigger than human lifetimes or history that it can be difficult to comprehend. Volcanoes live for a long, long time, and they can sleep for a long, long time. Just because a volcano hasn’t visibly done anything in all human history does not mean it’s dead!
I have a problem with the "active" term because it doesn't note a difference when a volcano erupts. The term dormant makes more sense for a non-eruptive phase from a volcano that is not extinct. Either that or there needs to be more categories. If a volcano that isn't visibly doing anything is considered active, then what is an eruption?! It's silly.
The need to distinguish when a volcano is currently erupting is why most countries have a color code or alert level system for their active volcanoes, with the lower levels noting levels of unrest or warning signs, and the higher levels noting an eruption in progress.
When it doesn't get any hot magma form the depths of our planet anymore and when it won't get any magma ever again, because it is cut off from the magma supply. That's the easiest way to know when it won't erupt again. Because, then it won't erupt ever again.
It’s fascinating to me that the scientific organizations that oversee the world’s volcanic activity don’t have more precise and carefully defined terms for the different categories of volcanic activity. I guess I shouldn’t be all that surprised given the controversy in recent years about the difference between planets, dwarf planets, and asteroids. The old ways of classifying things often don’t hold up well when you try to set precise boundaries between classifications. What exactly marks the dividing line between what makes a plant a tree and what makes it a shrub or a bush? Is a virus a living organism? Lots of things aren’t easily defined…
Your definitions are more generous than mine. Active means that it is spewing rock, dormant means that it is outgassing, and extinct means that it will never be exciting again. So, from where I am perched, literally, St Helens is active (cone building), Hoodster is dormant (Devil's Kitchen), and Tabor is extinct. Yellowstone is in a really really long dormant phase.
@@carolineleesi7643 Larch Mountain Sherrod Point? It is closer to Hood than Tabor but I haven't heard of anything volcanic, just a dead dike like much of the far north Gorge side of Hood.
We focus on the surface manifestations of volcanoes, but the important bits are the causal structures and processes below. The Yellowstone hotspot is active, but the former calderas to the southwest of its current location are definitely extinct. Subduction arc volcanic cones come and go on a whimsy, geologically speaking, but the underlying process continues until the subducting stops. In a sense the volcano just moves to a different spot. Still active, but not over there. So, when a new melt invades the location of a previously extinct volcano, is it really the same volcano? What about when an extinct stratovolcano is exposed to extension rifting, a completely separate geological process to what originally produced it? Doesn't sound to me like a re-activation. My point: nature doesn't care about labels. Labels are our way to direct people's attention to a perceived threat, but essentially meaningless.
Long Valley is a super volcano that they do not even know why it is there other than rifting in different directions, but its magma chamber has been active for thousands of years. ruclips.net/video/DBiZP1Lc-Ms/видео.html
@@St.Linguini_of_Pesto Fuji is pure esthetic, a nature wonder. Kili' stands for strenght... the highest free standing mountain on the planet. I dream to climb it. 🙂
Given that Kilimanjaro's Kibo crater still has high temperature fumaroles venting gas, all signs point to hot magma still being present inside Kilimanjaro
Ghub, would u care to explain what an active magma Chamber means? And How can a magma Chamber not produce eruptions for over 50k years and still remain "active" ?
Volcanoes with large magma bodies can retain active magma chambers for more than 100,000 years. In fact, there is a more than 1 million year old magma body in the Clear Lake volcanic field which is used as the source for geothermal power.
@@GeologyHub cool, i have so many questions dude, i Just love geology. I know u already answered my First one, but i have another cool one. I live in Rio de Janeiro Brazil, and this Summer has been unusually wet, would you say honga Tonga eruption in the beggining of the year may have something to do with it? Do you know If there was any aerial / up close footage of the plinian part of the eruption? The event was so unique and unexpected that i imagine huge scientific interest behind it
How long did it take you to complete your education and how old were you when you started? I saw a documentary about earthquakes that stated there is a chunk of either Pacific plate or another smaller plate that subducted under the North American plate millions of years ago that has traveled under it until it is nearing the east coast. How would that have affected volcanoes like Yellowstone if at all?
aren’t there certain types of volcanos, I think there's one near mexico city and another in New Mexico, that will never 'errupt again, have only errupted once in the last 10,000 years,, and if i’m not mistaken on that, how do we know?
One way is to look at how seismic waves propagate through a medium as s waves can't pass through liquids thus if you see a gap in s waves that is a good sign you have a liquid or partially liquid body down there. Now it terns out to be a bit tricky even then as we now know volcanoes can in relatively short intervals transform from a relatively solid rock slush into liquid magma due to dynamical changes in the system i.e. fresh intrusions reinjecting heat into an existing magma chamber, or sharp changes in underlying pressure, chemical compositional shifts via crystal fractionalization or magmatic dikes connecting with chemically distinct magmatic bodies and undergoing mixing etc. and there are likely even more processes we don't yet fully understand as its an actively developing field. Based on the Crazy Eocene lecture series on Nick Zentner's channel involving active researchers and their ongoing work there is some fascinating discoveries which seem to be pointing to a more complex interconnected and dynamic model of plate tectonics. One example for how this may interplay with reactivating/renewing volcanism is that the dates for the Tertiary ignimbrite flare up in both volcanic deposits and intrusive plutons and or batholiths is that these dates appear to coincide with the exposure of metamorphic core complexes and block fault extensional processes. This suggests that the reactivation of volcanism was at least in some way related to the once towering Laramide orogeny getting drastically extended over time starting from the North and propagating south over time, that would result in major decompression of deep batholiths for the ancient highly developed volcanic arc which due to thermodynamics should have resulted in the production of large amounts of heat and upwards dominated pressure which could offer a promising explanation for why that episode was so extreme. Reactivated crystal slush tends to be far more explosive as its generally high silica material so its actually these evolved magma chambers which can become some of the most dangerous as these systems can and do evolve on timescales of tens to hundreds of thousands or even in some more extreme cases millions of years as the size of a magma body and the amount of heat flux it receives or doesn't receive affects how long it takes to cool down and finally fully solidify and this makes telling which magmatic bodies are liable to erupt in the future or not tricky if not impossible.
A live magma chamber will often have visible signs of its presence. For example, there may be volcanic gas emissions from the magma, geothermal features from the volcanic heat (hot springs, geysers, fumaroles et al), and ground deformation and seismic activity as magma moves underground. A volcano displaying any of these signs should be considered active. Determining when a volcano will never erupt again is trickier, but can also rely on visual signs. If you're looking at a volcano that doesn't show any magmatic "signs of life" like I just described, and hasn't erupted in so long that its edifice is being visibly eroded away, then it probably is extinct. Deeper signs of a volcano being active or extinct are in that great post by @Dragarth1.
Time after time I have tried to figure out estimates as to how much CO² a vei8 volcano wouod emit and I dont know where to look. I cant even figure out how much CO² is estimated to have been emitted from Mt Tambora a vei7 eruption. Does anybody have any insight into that?
Isn't the end of the last ice age in question though? Read recently that some geologists think the last i e agr is still ongoing and cycling between interglacial and glacial periods.
Yes we are still currently in an ice age. Ive actually never heard a geologist dispute that. We are just in an interglacial period. Typically people refer to the end of the last glaciation the end of the last iceage. But I think its just nomenclature not technically accurate.
The Google Earth terrain at Mt Edgecumbe dates to the 80s. Can you think why there isn't more recent satellite imagery? Is it hush hush for some reason?
Yet there's volcanic fields that went 75,000 years without activity then ... they're active again not always a big eruption but active nonetheless so when do we really call a particular volcano or an volcanic field extinct.
Hawaiian volcanoes are rather interesting with this definition debate. For example, volcanoes on Oahu and Kauai that have not erupted since the last ice age could potentially erupt again.
volcanoes in Kauai and Oahu are distant from the magma source and will not erupt again. There are no seismic indications of any magma activity. Volcanoes on Molokai are extinct also, for the same reason. West Maui is also extinct, but Haleakala is just "inactive"...kinda between active and dormant. Last rift zone eruption was about 1400 or so. There are periodic seismic indications of rift zone magma movement. About a decade ago, there were enough indications that insurers would not write policies for properties in or near the southwest rift zone. All volcanoes in the Big Island are either active or "inactive"....would not say dormant. As noted, I think there needs to be another designation..."inactive"...covering the time frame between active and dormant.
We have only been able to drill 40,000 ft or 12 km into the earth, after that it was too hot, the rock turned spongy and melted the bits. Quakes below this level are baffling due to the squishy nature of the rock. Perhaps core generated disturbances. Magma could melt thru any point, volcanos are the weak points
Partly true however note that the boring through a lot of rock is not a passive process on the surrounding environment beyond just mechanical effects as temperature and pressure are directly linked thus you have to consider the effect of removing material above a layer of rock will do to its thermodynamic state. In many cases the net result is rapid decompression inducing melting which should act exactly as you described as material expands to fill the gap. The greater the change in pressure the more extreme the associated change in temperature would be depending of course on the substances in question
BC ( before christ ) and AD ( anno domini, latin for the year of our lord ), have been used for I dont even know how long. It seems most often now many scientists prefer either BCE ( before common era ) or CE ( common era ), or they like to use BP ( before present ). The push to change it is because of the religious conotations to what has been traditionally used ( bc and ad ). It can get confusing 1500 bp would equal 522 ad or 522 ce. 2100 bp would equal 78 bc or bce lol. I hate it I prefer the original system.
Mayotte volcanoes formed 7 to 4.5 million years ago. Suspected minor disturbance 7-10 thousand yrs ago. Huge boom in 2018. This one gives volcanic hope to any specified volcanoes.
![GUILTY GEAR -STRIVE- Season Pass 4 Playable Character #1 [Queen Dizzy] Trailer](http://i.ytimg.com/vi/nXDsAgYXXv4/mqdefault.jpg)
i'm very glad you're making these more general videos for definitions and theory.
Thanks for these helpful discussions of volcano basics.
I fully agree with your opinions of ranking, over and above any others.
Why are Three Fingered Jack etc. Volcanoes considered Extinct? Remember 4 peaked in Alaska was Extinct yet it erupted in 2006. Could you explain further about Extinct Volcanoes? Thank you
It was likely misunderstood and there was also no sensors or anything to detect signs of life
I think the only ones that can be conclusively ruled out as extinct are the ones that have long been cut off from any potential magma source, although the longer since the last eruption the less likely any renewed activity is. Hard to draw a firm line on how long time is enough to be designated as extinct since many types of volcanoes work on entirely different timescales.
Geologic time is so much bigger than human lifetimes or history that it can be difficult to comprehend. Volcanoes live for a long, long time, and they can sleep for a long, long time. Just because a volcano hasn’t visibly done anything in all human history does not mean it’s dead!
Great video, really informative and interesting!
I have a problem with the "active" term because it doesn't note a difference when a volcano erupts. The term dormant makes more sense for a non-eruptive phase from a volcano that is not extinct. Either that or there needs to be more categories. If a volcano that isn't visibly doing anything is considered active, then what is an eruption?! It's silly.
The need to distinguish when a volcano is currently erupting is why most countries have a color code or alert level system for their active volcanoes, with the lower levels noting levels of unrest or warning signs, and the higher levels noting an eruption in progress.
Thank you for the definitions. Do you consider the Boring volcanic field to be active, dormant or extinct?
At least it isn't boring. 😜
It's safe to assume that it is not exciting, intriguing, or fun.
@@denisenilsson1366 LOL
Very interesting. May I ask, how is it determined a volcano will never erupt again?
If it hasn’t erupted over a million years
@@Vesuviusisking not entirely true for super volcanoes though
@@jakealter5504 I thought we’re talking about the usual volcanoes
I would say that this volcano does not have a magma chamber anymore
When it doesn't get any hot magma form the depths of our planet anymore and when it won't get any magma ever again, because it is cut off from the magma supply.
That's the easiest way to know when it won't erupt again.
Because, then it won't erupt ever again.
Woot Mt Hood! I always get excited when anything Oregon comes up XD.
It’s fascinating to me that the scientific organizations that oversee the world’s volcanic activity don’t have more precise and carefully defined terms for the different categories of volcanic activity. I guess I shouldn’t be all that surprised given the controversy in recent years about the difference between planets, dwarf planets, and asteroids. The old ways of classifying things often don’t hold up well when you try to set precise boundaries between classifications. What exactly marks the dividing line between what makes a plant a tree and what makes it a shrub or a bush? Is a virus a living organism? Lots of things aren’t easily defined…
Your definitions are more generous than mine. Active means that it is spewing rock, dormant means that it is outgassing, and extinct means that it will never be exciting again. So, from where I am perched, literally, St Helens is active (cone building), Hoodster is dormant (Devil's Kitchen), and Tabor is extinct. Yellowstone is in a really really long dormant phase.
But Oregon Larch Mountain is building and venting.
@@carolineleesi7643 Larch Mountain Sherrod Point? It is closer to Hood than Tabor but I haven't heard of anything volcanic, just a dead dike like much of the far north Gorge side of Hood.
Thanks i have to take an test tomorrow about mauna loa
Oh, damn! The gauntlet has been laid down 😳
I've heard that technically we are still in an ice age until the last bits of ice leave Greenland and Antarctica.
Most people living in Sitka, actually believe that Mt. Edgecumbe volcano is extinct, 😆
Thank you for giving a clear definition for everyone.
We focus on the surface manifestations of volcanoes, but the important bits are the causal structures and processes below.
The Yellowstone hotspot is active, but the former calderas to the southwest of its current location are definitely extinct.
Subduction arc volcanic cones come and go on a whimsy, geologically speaking, but the underlying process continues until the subducting stops. In a sense the volcano just moves to a different spot. Still active, but not over there.
So, when a new melt invades the location of a previously extinct volcano, is it really the same volcano?
What about when an extinct stratovolcano is exposed to extension rifting, a completely separate geological process to what originally produced it? Doesn't sound to me like a re-activation.
My point: nature doesn't care about labels. Labels are our way to direct people's attention to a perceived threat, but essentially meaningless.
Long Valley is a super volcano that they do not even know why it is there other than rifting in different directions, but its magma chamber has been active for thousands of years.
ruclips.net/video/DBiZP1Lc-Ms/видео.html
Would you classify Kilimanjaro as dormant or active? (My favourite volcano in the world…)
It’s Dormant right now
Kilimanjaro is beautiful.. Fuji is my personal favorite.
@@St.Linguini_of_Pesto Fuji is pure esthetic, a nature wonder. Kili' stands for strenght... the highest free standing mountain on the planet. I dream to climb it. 🙂
Given that Kilimanjaro's Kibo crater still has high temperature fumaroles venting gas, all signs point to hot magma still being present inside Kilimanjaro
Ghub, would u care to explain what an active magma Chamber means? And How can a magma Chamber not produce eruptions for over 50k years and still remain "active" ?
Volcanoes with large magma bodies can retain active magma chambers for more than 100,000 years. In fact, there is a more than 1 million year old magma body in the Clear Lake volcanic field which is used as the source for geothermal power.
@@GeologyHub cool, i have so many questions dude, i Just love geology. I know u already answered my First one, but i have another cool one. I live in Rio de Janeiro Brazil, and this Summer has been unusually wet, would you say honga Tonga eruption in the beggining of the year may have something to do with it? Do you know If there was any aerial / up close footage of the plinian part of the eruption? The event was so unique and unexpected that i imagine huge scientific interest behind it
How long did it take you to complete your education and how old were you when you started?
I saw a documentary about earthquakes that stated there is a chunk of either Pacific plate or another smaller plate that subducted under the North American plate millions of years ago that has traveled under it until it is nearing the east coast. How would that have affected volcanoes like Yellowstone if at all?
Take a look at the extinct volcano in Vermont. Mount Ascutney
Wait, wut???😳 I live in New York State, thats too close😬
I thought extinct volcanoes are volcanoes that no longer exist
aren’t there certain types of volcanos, I think there's one near mexico city and another in New Mexico, that will never 'errupt again, have only errupted once in the last 10,000 years,, and if i’m not mistaken on that, how do we know?
Some are called quiescent volcanoes, and there are over 700 quiescent volcanoes on Earth
Why did my brain read that as "quesadilla volcanoes"?
OIC. Dindin time
Extinct can, rarely, be upgraded to active. For example, the Bolshaya Udina volcanic complex.
Did you make this one because the recent "OMG Yellowstone is going to kill us all" videos creeping up on RUclips?
How to determine whether magma chambers are active or not? And how to determine a Vulcano cannot erupt ever again?
One way is to look at how seismic waves propagate through a medium as s waves can't pass through liquids thus if you see a gap in s waves that is a good sign you have a liquid or partially liquid body down there.
Now it terns out to be a bit tricky even then as we now know volcanoes can in relatively short intervals transform from a relatively solid rock slush into liquid magma due to dynamical changes in the system i.e. fresh intrusions reinjecting heat into an existing magma chamber, or sharp changes in underlying pressure, chemical compositional shifts via crystal fractionalization or magmatic dikes connecting with chemically distinct magmatic bodies and undergoing mixing etc. and there are likely even more processes we don't yet fully understand as its an actively developing field.
Based on the Crazy Eocene lecture series on Nick Zentner's channel involving active researchers and their ongoing work there is some fascinating discoveries which seem to be pointing to a more complex interconnected and dynamic model of plate tectonics.
One example for how this may interplay with reactivating/renewing volcanism is that the dates for the Tertiary ignimbrite flare up in both volcanic deposits and intrusive plutons and or batholiths is that these dates appear to coincide with the exposure of metamorphic core complexes and block fault extensional processes.
This suggests that the reactivation of volcanism was at least in some way related to the once towering Laramide orogeny getting drastically extended over time starting from the North and propagating south over time, that would result in major decompression of deep batholiths for the ancient highly developed volcanic arc which due to thermodynamics should have resulted in the production of large amounts of heat and upwards dominated pressure which could offer a promising explanation for why that episode was so extreme.
Reactivated crystal slush tends to be far more explosive as its generally high silica material so its actually these evolved magma chambers which can become some of the most dangerous as these systems can and do evolve on timescales of tens to hundreds of thousands or even in some more extreme cases millions of years as the size of a magma body and the amount of heat flux it receives or doesn't receive affects how long it takes to cool down and finally fully solidify and this makes telling which magmatic bodies are liable to erupt in the future or not tricky if not impossible.
A live magma chamber will often have visible signs of its presence. For example, there may be volcanic gas emissions from the magma, geothermal features from the volcanic heat (hot springs, geysers, fumaroles et al), and ground deformation and seismic activity as magma moves underground. A volcano displaying any of these signs should be considered active.
Determining when a volcano will never erupt again is trickier, but can also rely on visual signs. If you're looking at a volcano that doesn't show any magmatic "signs of life" like I just described, and hasn't erupted in so long that its edifice is being visibly eroded away, then it probably is extinct. Deeper signs of a volcano being active or extinct are in that great post by @Dragarth1.
What do you know about Table Mountain (Tuolumne County, California)
The Roccamonfina volcano's last eruption was 50000 years ago. I guess that volcano is border line between dormant and extinct
I live near Mount Rainier and it's constantly being monitored
Is diamond head extinct or just dormant?
Time after time I have tried to figure out estimates as to how much CO² a vei8 volcano wouod emit and I dont know where to look. I cant even figure out how much CO² is estimated to have been emitted from Mt Tambora a vei7 eruption. Does anybody have any insight into that?
Isn't the end of the last ice age in question though? Read recently that some geologists think the last i e agr is still ongoing and cycling between interglacial and glacial periods.
Yes we are still currently in an ice age. Ive actually never heard a geologist dispute that. We are just in an interglacial period. Typically people refer to the end of the last glaciation the end of the last iceage. But I think its just nomenclature not technically accurate.
Now for Canada
Howbout Chile's Mount Chaitén for a Topic?
The Google Earth terrain at Mt Edgecumbe dates to the 80s. Can you think why there isn't more recent satellite imagery? Is it hush hush for some reason?
Yet there's volcanic fields that went 75,000 years without activity then ... they're active again not always a big eruption but active nonetheless so when do we really call a particular volcano or an volcanic field extinct.
Hawaiian volcanoes are rather interesting with this definition debate. For example, volcanoes on Oahu and Kauai that have not erupted since the last ice age could potentially erupt again.
volcanoes in Kauai and Oahu are distant from the magma source and will not erupt again. There are no seismic indications of any magma activity. Volcanoes on Molokai are extinct also, for the same reason. West Maui is also extinct, but Haleakala is just "inactive"...kinda between active and dormant. Last rift zone eruption was about 1400 or so. There are periodic seismic indications of rift zone magma movement. About a decade ago, there were enough indications that insurers would not write policies for properties in or near the southwest rift zone. All volcanoes in the Big Island are either active or "inactive"....would not say dormant. As noted, I think there needs to be another designation..."inactive"...covering the time frame between active and dormant.
How is it possible to know a volcano will never erupt again?
Look at la garita
Alaska is watching =]
We have only been able to drill 40,000 ft or 12 km into the earth, after that it was too hot, the rock turned spongy and melted the bits. Quakes below this level are baffling due to the squishy nature of the rock. Perhaps core generated disturbances. Magma could melt thru any point, volcanos are the weak points
Partly true however note that the boring through a lot of rock is not a passive process on the surrounding environment beyond just mechanical effects as temperature and pressure are directly linked thus you have to consider the effect of removing material above a layer of rock will do to its thermodynamic state. In many cases the net result is rapid decompression inducing melting which should act exactly as you described as material expands to fill the gap. The greater the change in pressure the more extreme the associated change in temperature would be depending of course on the substances in question
Mammoth Lakes?
What’s it got to do with the last ice age? That seems on the face of it to be an arbitrary line.
Intermittently active and currently active are both not totally asleep 😜
BC and AD = why are u ppl in today's world changing the names??
BC ( before christ ) and AD ( anno domini, latin for the year of our lord ), have been used for I dont even know how long. It seems most often now many scientists prefer either BCE ( before common era ) or CE ( common era ), or they like to use BP ( before present ). The push to change it is because of the religious conotations to what has been traditionally used ( bc and ad ). It can get confusing 1500 bp would equal 522 ad or 522 ce. 2100 bp would equal 78 bc or bce lol. I hate it I prefer the original system.
@@justincosby2258 it is just too bad ppl can't be happy with what their forefathers did
Mayotte volcanoes formed 7 to 4.5 million years ago. Suspected minor disturbance 7-10 thousand yrs ago. Huge boom in 2018. This one gives volcanic hope to any specified volcanoes.
Kilauea volcano i think she's goner but not kilauea volcano then she's not
"if you would like to request a pacific topic" hehe
You talk about U.S. Volcanoes, forgot Spain, Italy, Japan and Mexico with great active. Very scientific and nice explain, but poor video.
Then why you saw
@@veenasudh Because i love the geology and science, that's why.
Or jailed
Best time for Canada to experiance next I won be presoin
How is dating the end of the last Ice Age to within a decade justified?