Quick correction of a slip of the tongue -- it's subduction of the Juan de Fuca plate that is fueling volcanism in the Cascades. Also, the map showing ash distribution only includes that part of the Mount St. Helens ash fall that was more than an inch. Lesser amounts fell over a much broader area. You can see a generalized map of this area in the USA at pubs.usgs.gov/gip/msh/ash.html.
Thanks for these reports! You always do a great job of explaining things in a way that is easy for a layperson to understand. I always look forward to the updates because I find Yellowstone a fascinating place and enjoy learning more about it
The range of ash from St Helens is always underestimated. We had considerable ash drop east past Butte Montana. and some spots in the mountains received heavier amounts. I experienced this first hand in the Georgetown Lake area near Philipsburg when visibility was reduced to less than 50 yards.
You're right -- the map shown in this video only indicates the area of thickest ash fall, where it was more than an inch or two. But there was still noticeable fall over a broad area east of the volcano. Another map showing that broader area in the USA is at pubs.usgs.gov/gip/msh/ash.html.
I have 2 jars of ashes from the last eruption at mt st Helen’s. My aunt lived 30 miles from the mountain and was able to watch the initial eruption. Went out after to collect some ashes.
...this bout is like putting an ant up against an elephant! I love the cascades and have hiked and camped from Shasta to Garibaldi for years. I listened to a fascinating lecture on estimating eruptions from remnants like welded tuff/ignimbrite. (not a geologist, is that spelled right?) The speaker offered analysis and modeling of deposits of various ages/lava compositions, sizes of eruptions etc and is quite convinced that we have wildly underestimated the volume of essentially all VEI-8 eruptions. There's one caldera, I think Long Valley, so 2-ish hours from Los Angeles, is the one, but I've also seen 10,000km³+ for La Garita. Geology Hub, another fantastic channel has a video including or dedicated to it, but I actually hadn't gotten to it yet, now I'm even more interested to find out what has been found and how it can be explained.
Yes, you spelled it correctly! Caldera-forming eruptions usually produce ignimbrites just because of the volume and thickness of ash deposits. Estimating their thicknesses can be a challenge where exposures are poor. Much of the ignimbrite volume can be found in the source caldera itself -- the ash basically falls back and fills in part of the hole that was created during the eruption. Without drilling records or serendipitous exposures, it can be hard to know the thickness of the deposits within the calderas. In the case of the big calderas of the San Juans in Colorado, like La Garita, there has been enough erosion to be able to see the intracaldera thicknesses.
Fortunately, there's no real indication of Yellowstone becoming more active anytime soon. The magma chamber is mostly solid (we know this from seismic imaging, which is sort of like taking an MRI of the subsurface), and there's no sign of any rejuvenation. Most eruptions there are lava flows, not massive explosions, but even a lava flow event needs a supply of eruptible magma.
Great Presentation Clear, concise & informative😊 Would like to know if there are any such webinars on the tectonic plates & volatility in S. Cascade range ie: Pelican Butte, Crater Lake etc. Looking for USGS info for this region. Would appreciate a "where to start"🤔
The Cascades and California Volcano Observatory websites have a lot of information: www.usgs.gov/observatories/cvo www.usgs.gov/observatories/calvo And there's a public talk from a few years ago about the Cascades at www.usgs.gov/media/videos/pubtalk-22018-usgs-cascades-volcano-observatory. Nick Zentner (Central Washington University) also does a huge number of UA-cam videos about geology, including the Cascades, so you'll probably find somethin in his collection that would be interesting.
Those smaller eruptions are far more common than the big explosions. Since the last big caldera-forming eruption 631,000 years ago there have been a few dozen lava flows (most recently about 70,000 years ago, so in an absolute sense they still aren't terribly common). These have largely filled the caldera, especially on the west side. There's more information about the occurrence and timing of these flows at www.usgs.gov/observatories/yvo/news/lotta-lava-new-insights-timing-yellowstones-most-recent-rhyolite-eruptions.
I know the risk of a major eruption at Yellowstone in the near term is negligible. But I'm curious if there is a risk of a phreatic eruption at any given time given all the geothermal activity?
Not necessarily a phreatic eruption, but a hydrothermal (steam) explosion is definitely a hazard. Water flashing to steam can drive explosions that range from small -- the formation of Porkchop Geyser in 1989, for example -- to huge, like Mary Bay, which is 1.5 miles across and is the largest known hydrothermal explosion crater in the world. These explosions do not involve magma, but rather changes in pressure in the shallow subsurface that can cause rapid phase changes (liquid water to steam). Small hydrothermal explosions occur somewhere in Yellowstone about every year or so, but usually in the backcountry, where they escape notice. Certainly these explosions are an underappreciated hazard in the region. We've got some information on this at www.usgs.gov/observatories/yvo/news/real-hazards-yellowstone and www.usgs.gov/observatories/yvo/news/if-eruption-so-unlikely-why-do-we-monitor-yellowstone-all.
Thank you for sharing this information. I experienced Mt. St. Helen’s eruption. It was not fun times - especially as an asthmatic. Imagining what a Yellowstone eruption would be like is 🥺😞. This planet is beautiful in many ways, but she’s also not here to play with us. You can see by how aggressively she is trying to reset herself by any means necessary. She erased us before and she’ll do it again. Get it together, humans! Also, stop violating everything at Yellowstone. Shame on you!
I hate to say this, but im replacing the sound of your voice in my head with Randy Marsh's voice. And it's incredible, truly incredible. You yourself sir, have a wonderful voice for relaying information, i just thought that was funny. P.s. 1:55 Your map thinks Tennessee and North Carolina are one state
That's the best monitored volcano in the Cascade Range! You can see a map of monitoring stations at www.usgs.gov/volcanoes/mount-st.-helens. Click on any of the sites to see the data!
At 1:07 you asked *_"I don't think we need to talk about Yellowstone's explosive potential, right?"_* Given the number of Yellowstone doomsday videos on UA-cam, I think you *should* talk about it, and you should do it _every month_. Because all of those videos that have inaccurate information are scaring people who don't know anything about Yellowstone. Yes, Mt. St. Helens is rather weak when compared to Yellowstone. But people need to know what geology experts have to say about the fear mongering doomsday stuff people are posting here on UA-cam.
Unfortunately, there are a number of tinfoil hat wearers who believe that Yellowstone will erupt any second and that the government is hiding that. I even had to correct my next door neighbor, who usually talks sense, but he was talked into this doomsday stuff.
The claim "Mount Saint Helens is the most explosive volcano in the cascade range" is contestable. In the last 100 years maybe. But in the last millenia; Newberry, Mazama, and Three Sisters volcanoes would all like a word. As well as various other rhyolitic centers within the cascade range...
It's definitely true that some Cascade volcanoes have had large explosive eruptions. Glacier Peak has had some biggies, too! But in terms of frequency of explosive eruptions, Mount St. Helens leaves them all in the dust. There's more about the history of the volcano over the last few thousand years at www.usgs.gov/volcanoes/mount-st.-helens/science/holocene-activity-prior-may-18-1980-eruption.
File that under "strange but true." Volcanism has been occurring in the region for 275,000 years, but the mountain we know today only started growing about 3900 years ago. More info on that at www.usgs.gov/volcanoes/mount-st.-helens/science/holocene-activity-prior-may-18-1980-eruption.
Not a mistake! There has been volcanism in the area for 275,000 years. But the edifice that we know today didn't really start growing until about 4000 years ago. More on the history of today's Mount St. Helens at www.usgs.gov/volcanoes/mount-st.-helens/science/holocene-activity-prior-may-18-1980-eruption.
I lived there and there was no lava flow unless it was under the ground. There were pyroclastic flows. I watched it from the time it started erupting. Lived 12 air miles from Mount Saint Helen's and worked for the GPNF.
Pyroclastic flows from the most recent eruption, yes. The domes that grew in the crater can almost be counted, though they were more like squeezing out toothpaste and never really ‘flowed’. Prior eruptions of MSH did produce lava flows, enough to build the mountain. He could perhaps have been more specific on that bit.
The most recent lava flows at Mount St. Helens occurred after the May 18, 1980, explosion. Lava erupted in a number of discrete episodes between 1980 and 1986, and then again in a continuous episode during 2004-2008. You can see a time-lapse movie of the more recent lava dome eruption at ua-cam.com/video/h6B1myUKAS4/v-deo.html.
@@usgs I have never heard of that and I was there until 1993. We had pumice October 1980. I will ask my FS friends about the 2004-2008 lava. I still live in the area and retired in 2007.
@@usgs We never called it a lava flow. We new it was lava, but we called it dome growth. You made it sound like the lava flows we've been seeing in Iceland and Hawaii.
@@daphnekivinen9482 Yes, it's typically referred to as a lava dome when it just piles up around the vent, as it has done at Mount St. Helens. Very similar features are present in Yellowstone, although much larger in volume, and many of those also flowed pretty far from their vents because they were so big. In both cases, the flows are thick and the lava is basically solid when it erupts.
Quick correction of a slip of the tongue -- it's subduction of the Juan de Fuca plate that is fueling volcanism in the Cascades.
Also, the map showing ash distribution only includes that part of the Mount St. Helens ash fall that was more than an inch. Lesser amounts fell over a much broader area. You can see a generalized map of this area in the USA at pubs.usgs.gov/gip/msh/ash.html.
Great presentation- thank you! You should have WAY more visitors.
Thank you very much, Mike. Climbed St. Helens in 1976 with my Dad. A wonderful memory.
Well done Mike!
Thanks for these reports! You always do a great job of explaining things in a way that is easy for a layperson to understand. I always look forward to the updates because I find Yellowstone a fascinating place and enjoy learning more about it
I always enjoy these videos but I really enjoyed this one
The range of ash from St Helens is always underestimated. We had considerable ash drop east past Butte Montana. and some spots in the mountains received heavier amounts. I experienced this first hand in the Georgetown Lake area near Philipsburg when visibility was reduced to less than 50 yards.
You're right -- the map shown in this video only indicates the area of thickest ash fall, where it was more than an inch or two. But there was still noticeable fall over a broad area east of the volcano. Another map showing that broader area in the USA is at pubs.usgs.gov/gip/msh/ash.html.
Thanks for the presentation and update! Subscribed.
ty for this info i find it fascinating and shows me what mt rainer could do when it blows i live in one of the lahar areas for rainer
Next up : hummingbird vs. tyrannosaurus rex.
😂😂😂
Nah, it's grenade vs super nova
I was thinking Conner McGregor vs Hafthor Bjornsonn (there's a video of that somewhere on the web...)
Funny
I was on Mt. ST Hellen’s the year before it blew it top off.
Cool. It must have felt strange to see it after.
@@mary.b.93 Very strange.
Mike, ya might want to get some antacid for that NASTY indigestion you suffered at the end there! 😂😂
Thank you for explaining my constipation in detail!
Great report. Thank you.
Thanks
I have 2 jars of ashes from the last eruption at mt st Helen’s. My aunt lived 30 miles from the mountain and was able to watch the initial eruption. Went out after to collect some ashes.
tnks mike!
Cool comparison
...this bout is like putting an ant up against an elephant! I love the cascades and have hiked and camped from Shasta to Garibaldi for years. I listened to a fascinating lecture on estimating eruptions from remnants like welded tuff/ignimbrite. (not a geologist, is that spelled right?) The speaker offered analysis and modeling of deposits of various ages/lava compositions, sizes of eruptions etc and is quite convinced that we have wildly underestimated the volume of essentially all VEI-8 eruptions. There's one caldera, I think Long Valley, so 2-ish hours from Los Angeles, is the one, but I've also seen 10,000km³+ for La Garita. Geology Hub, another fantastic channel has a video including or dedicated to it, but I actually hadn't gotten to it yet, now I'm even more interested to find out what has been found and how it can be explained.
Yes, you spelled it correctly! Caldera-forming eruptions usually produce ignimbrites just because of the volume and thickness of ash deposits. Estimating their thicknesses can be a challenge where exposures are poor. Much of the ignimbrite volume can be found in the source caldera itself -- the ash basically falls back and fills in part of the hole that was created during the eruption. Without drilling records or serendipitous exposures, it can be hard to know the thickness of the deposits within the calderas. In the case of the big calderas of the San Juans in Colorado, like La Garita, there has been enough erosion to be able to see the intracaldera thicknesses.
@@usgs Awesome, thanks for the answer, I'm glad to have learned that my memory will return, in time.
Nobody knows when it will happen but we’ll know at the same time when it does go off.
Fortunately, there's no real indication of Yellowstone becoming more active anytime soon. The magma chamber is mostly solid (we know this from seismic imaging, which is sort of like taking an MRI of the subsurface), and there's no sign of any rejuvenation. Most eruptions there are lava flows, not massive explosions, but even a lava flow event needs a supply of eruptible magma.
I worked at Lake Lodge many many summers ago. Tourists: please take care of it.
Great Presentation Clear, concise & informative😊 Would like to know if there are any such webinars on the tectonic plates & volatility in S. Cascade range ie: Pelican Butte, Crater Lake etc. Looking for USGS info for this region. Would appreciate a "where to start"🤔
The Cascades and California Volcano Observatory websites have a lot of information:
www.usgs.gov/observatories/cvo
www.usgs.gov/observatories/calvo
And there's a public talk from a few years ago about the Cascades at www.usgs.gov/media/videos/pubtalk-22018-usgs-cascades-volcano-observatory. Nick Zentner (Central Washington University) also does a huge number of UA-cam videos about geology, including the Cascades, so you'll probably find somethin in his collection that would be interesting.
@@usgs Thank you great.😊🌍✌️
I have a question, we love to talk about the massive eruptions at Yellowstone, but how common are (relatively) small eruptions at yellowstone?
Those smaller eruptions are far more common than the big explosions. Since the last big caldera-forming eruption 631,000 years ago there have been a few dozen lava flows (most recently about 70,000 years ago, so in an absolute sense they still aren't terribly common). These have largely filled the caldera, especially on the west side. There's more information about the occurrence and timing of these flows at www.usgs.gov/observatories/yvo/news/lotta-lava-new-insights-timing-yellowstones-most-recent-rhyolite-eruptions.
@@usgs thanks!
i saw the thumbnail and i thought they were going to rap battle
Maybe a future idea? 🤣 🎤
Wow. We can comment now.
Exactly 44 years ago today my dad said "let it blow... What harm coikd it do?"
Your dad has one heck of a sense of humor lol
@@RyanLee809Not to mention an interesting accent.
@@FishKepr hahaha good point
I know the risk of a major eruption at Yellowstone in the near term is negligible. But I'm curious if there is a risk of a phreatic eruption at any given time given all the geothermal activity?
Not necessarily a phreatic eruption, but a hydrothermal (steam) explosion is definitely a hazard. Water flashing to steam can drive explosions that range from small -- the formation of Porkchop Geyser in 1989, for example -- to huge, like Mary Bay, which is 1.5 miles across and is the largest known hydrothermal explosion crater in the world. These explosions do not involve magma, but rather changes in pressure in the shallow subsurface that can cause rapid phase changes (liquid water to steam). Small hydrothermal explosions occur somewhere in Yellowstone about every year or so, but usually in the backcountry, where they escape notice. Certainly these explosions are an underappreciated hazard in the region. We've got some information on this at www.usgs.gov/observatories/yvo/news/real-hazards-yellowstone and www.usgs.gov/observatories/yvo/news/if-eruption-so-unlikely-why-do-we-monitor-yellowstone-all.
@@usgs interesting information. Thank you for sharing.
Thank you for sharing this information. I experienced Mt. St. Helen’s eruption. It was not fun times - especially as an asthmatic. Imagining what a Yellowstone eruption would be like is 🥺😞. This planet is beautiful in many ways, but she’s also not here to play with us. You can see by how aggressively she is trying to reset herself by any means necessary. She erased us before and she’ll do it again. Get it together, humans! Also, stop violating everything at Yellowstone. Shame on you!
You wouldn't have to worry about asthma if Yellowstone blew.
I hate to say this, but im replacing the sound of your voice in my head with Randy Marsh's voice. And it's incredible, truly incredible. You yourself sir, have a wonderful voice for relaying information, i just thought that was funny.
P.s. 1:55 Your map thinks Tennessee and North Carolina are one state
What, you've never heard of Tennelina? 🙃
Fun fact: Trey Parker's dad, Randolph "Randy" Parker, was a USGS geologist!
My great grandpa made an oil painting of Mt. St. Helens before it exploded.
Great presentation, miles ahead of most of the crap on UA-cam
We'd like to see the current monitoring efforts for MSH, too! :)
That's the best monitored volcano in the Cascade Range! You can see a map of monitoring stations at www.usgs.gov/volcanoes/mount-st.-helens. Click on any of the sites to see the data!
At 1:07 you asked *_"I don't think we need to talk about Yellowstone's explosive potential, right?"_*
Given the number of Yellowstone doomsday videos on UA-cam, I think you *should* talk about it, and you should do it _every month_. Because all of those videos that have inaccurate information are scaring people who don't know anything about Yellowstone. Yes, Mt. St. Helens is rather weak when compared to Yellowstone. But people need to know what geology experts have to say about the fear mongering doomsday stuff people are posting here on UA-cam.
Unfortunately, there are a number of tinfoil hat wearers who believe that Yellowstone will erupt any second and that the government is hiding that. I even had to correct my next door neighbor, who usually talks sense, but he was talked into this doomsday stuff.
The claim "Mount Saint Helens is the most explosive volcano in the cascade range" is contestable.
In the last 100 years maybe.
But in the last millenia; Newberry, Mazama, and Three Sisters volcanoes would all like a word.
As well as various other rhyolitic centers within the cascade range...
It's definitely true that some Cascade volcanoes have had large explosive eruptions. Glacier Peak has had some biggies, too! But in terms of frequency of explosive eruptions, Mount St. Helens leaves them all in the dust. There's more about the history of the volcano over the last few thousand years at www.usgs.gov/volcanoes/mount-st.-helens/science/holocene-activity-prior-may-18-1980-eruption.
Isn’t it the Juan de fuca plate not Pacific?
You're right -- good catch!
It's not part of the Pacific Plate, but it is beneath the Pacific Ocean.
Wait after eclipse than 40 day than what next ? You X mark already..
Wait, what? Mt St Helens is only about 4000 years old??
File that under "strange but true." Volcanism has been occurring in the region for 275,000 years, but the mountain we know today only started growing about 3900 years ago. More info on that at www.usgs.gov/volcanoes/mount-st.-helens/science/holocene-activity-prior-may-18-1980-eruption.
2:25, you say mt. St. Helens mountain didn't even form until 4000 years ago. Is that true or a mistake?
Not a mistake! There has been volcanism in the area for 275,000 years. But the edifice that we know today didn't really start growing until about 4000 years ago. More on the history of today's Mount St. Helens at www.usgs.gov/volcanoes/mount-st.-helens/science/holocene-activity-prior-may-18-1980-eruption.
I like that hoodie
I lived there and there was no lava flow unless it was under the ground. There were pyroclastic flows. I watched it from the time it started erupting. Lived 12 air miles from Mount Saint Helen's and worked for the GPNF.
Pyroclastic flows from the most recent eruption, yes. The domes that grew in the crater can almost be counted, though they were more like squeezing out toothpaste and never really ‘flowed’. Prior eruptions of MSH did produce lava flows, enough to build the mountain. He could perhaps have been more specific on that bit.
The most recent lava flows at Mount St. Helens occurred after the May 18, 1980, explosion. Lava erupted in a number of discrete episodes between 1980 and 1986, and then again in a continuous episode during 2004-2008. You can see a time-lapse movie of the more recent lava dome eruption at ua-cam.com/video/h6B1myUKAS4/v-deo.html.
@@usgs I have never heard of that and I was there until 1993. We had pumice October 1980. I will ask my FS friends about the 2004-2008 lava. I still live in the area and retired in 2007.
@@usgs We never called it a lava flow. We new it was lava, but we called it dome growth. You made it sound like the lava flows we've been seeing in Iceland and Hawaii.
@@daphnekivinen9482 Yes, it's typically referred to as a lava dome when it just piles up around the vent, as it has done at Mount St. Helens. Very similar features are present in Yellowstone, although much larger in volume, and many of those also flowed pretty far from their vents because they were so big. In both cases, the flows are thick and the lava is basically solid when it erupts.
Imagine holding in a gigantic fart for years... When you let it out, it goes...
make America magma again?
Yes , We are as individuals very short living on Earth ; So don't waist your time . Be knowledge seeker