Feels Xmas-y on GeologyHub lately -- as a HI resident seeing consecutive episodes on my home state's geology! Kohala's rarely talked about colloquially re: geology or volcanism, so loved the usual GH concise, easy-to-digest-for-laymen breakdown. Love it -- Aloha and looking forward to next EP, HI-based or not! 👍🌺
I find the geological history of the Hawaiian islands fascinating. Especially when you look at the Northwestern Hawaiian islands and then the remnants undersea. It’s cool. I know it’s a huge topic and I don’t know if you did it already, but it would be an idea. Thanks.
On the topic of giant slides, I’d like to hear more about the Akila slides and the megatsuamis they may have caused, alongside the recent research into megatsunami deposits found around Hawaii. Keep up the great work !
While you're doing a series on Hawaii, I'd like to see a video on the Mahukona volcano. I've stayed right there beside it several times and had no idea it was there until seeing this video. The Big Island is one of my favorite places to visit and its geology is fascinating.
Also interesting that Haleakala (on Maui) erupted so much more recently than Kohala (on Hawaii). Is that contrary to what would be expected from the direction of the plate sliding over the hot spot?
@@bruceching4078 True, and it's even erupted more recently than Mauna Kea which is far closer to the hot spot. But I think I remember Geology Hub making a video about eruptions on Oahu or nearby offshore still being a possibility!
Thank you for your highly informative and interesting videos. Several years ago we visited the summit of Kohala on our quest to visit all the Hawaiian (Big Island) volcanoes. It was a real challenge. Unlike other summits it is overgrown with a dense jungle. Also I believe that deep east facing valleys are results of accelerated erosion of cliffs after the partial collapse/slide of the island. Another interesting point - Mauna Kea grew on the flank of Kohala and so was helped to reach its spectacular height.
There's a saddle between MK and the Kohala mountains/volcano (where Waimea is). I live on MK along the Hamakua Coast and I wouldn't necessarily attribute MK's height to having "grown on the flanks of Kohala" especially when you consider MK's topography extending far deeper and many miles further underwater. Mauna Loa is also near the same height as MK and is further from Kohala. Btw, MK at one point was over 16,000 ft. It has diminished through its sheer weight and erosional processes.
So funny that you're doing these Hawaii videos right at this moment, along with several other unrelated content creators I follow also covering Hawaii... I just got back from a lengthy camping/exploration/geology trip out in Hawaii and have never been there before. I'll call that serendipity. Posting a video of my adventures in the next couple weeks for those who are interested. Got some great footage of Kilaheua's lava lake and up close footage with manta rays!
I always learn about new things about how planet Earth behaves from your great videos. The slump into the sea of that huge piece of the new island must have created an enormous tsunami. The resulting deep valleys are astonishing to see. Thank you so much for yet another terrific presentation.
I wonder whether the process that caused the 1955 eruption near Necker Island, or the fairly recent activity on East Maui, could one day trigger activity again at Kohala?
Haleakala on Maui is still in its post shield building, which is a stage of volcanism pre-rejuvenation. The forces still involved on Maui have long since died out in Kohala. If the 1955 eruption near Necker Island did in fact take place, it isn’t quite clear whether it was related to the Hawaiian hotspot / previously thought to be extinct shield volcanoes or, the theory I believe in, that it’s related to a secondary submarine range that the hotspot intermingles with.
The shape and general character of Kohala reminds me a lot more of the Azores than the other Hawaiian volcanoes. Maybe its the fact that its rift is remarkably linear, or the cinder cones on top, or that nice rich green around it, but it just gives off that vibe. Seems like a nice place.
The Northern Coast of Kohala is a beautiful place indeed. No roads through there, but a cool place to hike or see from a helicopter or boat. The lookout over the Palolu Valley and the trail down into it have awesome views.
I think it would be interesting if you made a video going into detail about the life cycle of Hawaiian and other similar shield volcanoes and how/why they progress through different stages
I have been watching very frequent, (Strombolian?) eruptions of Fuego in Guatemala. The camera is not very good, but the eruptions are beautiful and frequent. Have I missed your coverage of this volcano?
Can you do a piece on long valley? When I drive north to the islands valet, it’s filled with rugged cinderblocks, I’m curious as to how that all farmed.
Similar to how we see if a living thing is alive. Are there Signs of Life? Is there activity under the surface? Is there any seismic activity beneath it? Are there any fumaroles or gas vents? Etc
@BlackCell22 It could still be active as koolau much further away has erupted more recently than kohala and hawaiian volcanoes can go hundreds of thousands of years without erupt Any eruption at kohala won't be happening for a long time since a rejuvenation stage takes ages to happen
It's hard to know for absolutely certain but it has been in decline for a very long time, and as they decline eruptions become less and less frequent. Most volcanoes based on the official global volcanism program are declared extinct after the pass the >10,000 years since last eruption, although that isn't always neccesarily true as activity can persist far longer than that as there are many even older volcanoes that still have earthquakes and active fumaroles despite not erupting for even longer than 60,000 years. However the odds of an eruption from Kohala are so low they are nearly non-existent and likely several millenia in the far future in that case, Hawaiian volcanoes are quite well studied in all their stages of life and Kohala is therefore judged to be of minimal threat. You can read more about the stages of life here en.wikipedia.org/wiki/Evolution_of_Hawaiian_volcanoes
Would love to see a video on Hyalite Canyon south of Bozeman, MT. The main trail winds through hexagonal columns,(see Palisade Falls), ancient lahars and ahah flows. Hyalite drainage is named for the fact it is one of the few locations in the world that you can find hyalite opal just below Hyalite Peak, some even with play of color
I have driven the road from Havi to Wiamea many times and you drive right through parts of the volcano. In the right weather it is a beautiful sight to behold. It is very green most of the year. I believe Kohala means whale or whale hill in Hawaiian.
The island of Maui in Hawaii also has an active volcano. The are a series of proclastic cones. Maui is a separate island but it is not far away from the big island of Hawaii. Maui does have a fairly large settlement called Kahului.
@@bruceching4078 Wrong. Having erupted at least 10 times in the last 1000 years, Haleakela is classified as active by the USGS, even though many people consider it dormant.
@Bruce Ching It can still be active. It still has fairly young lava flows & the reason why they are no earthquake swarms could be the volcano is not showing any signs of erupting in near future but it is still active because it has erupted many times in the last 10,000 years but it is not showing any signs of erupting soon but it still has the capability of erupting again still.
There have been several recent videos on this channel covering both of those, though more are always welcomed! There were several videos a couple of months ago when Mauna Loa erupted and also when Kilauea's eruption resumed following its brief pause after Mauna Loa stopped.
Several people got good videos of a large land slide in San Diego where as section of the local cliffs collapsed. This might make a good topic, also recording a land slide from the business end seems sporting.
So, this will probably sound like a pretty stupid question, but wondering... How do we know these are 5 distinct volcanos and not just 'offshoots' from one much larger volcano? I mean, couldn't the five volcanos be getting their lava from the same opening in the mantal without us really being able to tell? I can understand calling each of the openings a different mound/mountain/lava dome, but how can we know for sure they aren't all part of one large volcano, sending material up from the core in different weak spots in the crust? If it's too stupid of a question, please ignore and apologies...
The only stupid question is the one unasked. I do hope Geology Hub will answer this question. When is a volcano a volcano, and not a vent of another volcano?
The Big Island volcanoes each have their own magma plumbing, unique chemistry, and individual behavior. If they were just five vents of one volcano they would be much more similar to each other.
This question is far from stupid, and gets to the heart of what makes volcanism so interesting. Mauna Loa and Kilauea are a great example: for many years, geologists though Kilauea was likely a particularly large vent off of Mauna Loa.
An even more interesting case is the Taupo Volcanic Zone. In many ways, it behaves like one gargantuan volcanic field with a nasty habit for large calderas, but at the same time there are distinct volcanic systems within it with fairly unique behavior. It feels like its almost right on the borderline between being one or many volcanoes.
It isn't considered part of the Big Island because it's not above water and not connected to the Big Island by land. If/when it rises above the ocean surface and becomes connected by land to Mauna Loa and/or Kilauea, then it would become part of the Big Island. But that almost certainly won't happen anywhere remotely close to any of our lifetimes.
I love residing here in Hawaii, it’s a wonderful place to live. However, living in paradise does come with it’s own dangers, erupting volcanoes, tsunamis and hurricanes. I read a story a few years ago about a erupting submarine volcano between Kauai and Oahu spotted by some US Navy pilots and some airline pilots in either 1956 or 1958, can’t remember which? Living at the base of a volcano, I just pray that nothing happens in my lifetime. I know that the whole state of Hawaii could be on top of a hot zone if magma should make it’s move. 🤣😂🤣
Yeah, I'm pretty sure I've seen a video here on UA-cam about that submarine eruption between Oahu and Kauai. I think it was either on this channel or on The History Guy, but I forget which.
I'm not quite willing to write off a volcano as "extinct" when it's so close to 4 that are active, and not far from another (Haleakala) which has a tiny but non-zero chance of waking up in the future. This same channel did a video on Easter Island a year ago, which hasn't had a documented eruption in 10,000 years: the youngest rocks of its Rano Kau volcano are roughly 120,000 years old, but it is still considered active, as is its neighbor Terevaka. Easter Island is a totally different hot spot system, but the setup (three volcanoes in close proximity, two considered active with one "extinct") is similar to the Big Island. This makes me ask, how much do we actually know about Kohala's underground plumbing and its relationship to the plumbing of the known active Hawaiian giants?
With Haleakala's most recent eruption being only a few hundred years ago, I wouldn't call it a tiny chance of re-awakening at all. With 10 known eruptions in the last 1,000 years, it seems like actually quite a large chance that it will eventually erupt again, though it probably won't ever be as active as Kilauea or Mauna Loa again. And, for what it's worth, while it's on a different island, Kohala is actually quite close to Haleakala. The channel between them is less than 30 miles wide. You can easily see one from the other on a clear day. Whereas it's about 55 miles from Kohala to Kilauea and only slightly less than that from Kohala to the summit of Mauna Loa (though, of course, Mauna Loa is huge and the Northwestern-most flows from it are only a few miles from Kohala.)
I still only consider a volcano extinct if it goes 100,000 years without erupting. I do think they should use ground penetrating radar to see if any magma is left underneath the volcano before declaring it’s extinct.
I don't think remaining magma is neccesarily a good way to judge, many old volcanoes still have magma left that cools and hardens in their chambers after they have become extinct, it's one of the way ancient volcanoes are discovered as the hardened magma chamber erodes at a different rate from the outside of volcano and you get for example volcanic plugs left after the rest of the mountain has eroded away. The big key I think would be if Kohala could receive a small batch of fresh lava that may either erupt independently as a new cinder cone or remobilize some of the old stale magma into for example a lava dome eruption. However with the low rate of eruptions and long time spent it is unlikely Kohala receives much if any fresh lava from the hotspot. It's far likelier that any other volcano on big island or even Haleakala on Maui would erupt rather than Kohala
@@Arthion I’m talking about having a magma chamber that could still have a eruption. I know magma will be in it a long time until it cools. We have the technology now to know if there’s still enough magma underneath a volcano for it to erupt again.
@@bigrooster6893 I mean the quantity isn't so much the big deal as the state of the magma in it, if it is too stale and hardened or molten enough. If it has sat there for 60k + years it's unlikely to change unless you add fresh stuff to the mix.
Yup, in the rare cases that you have high eruptive rates of viscous magma without much gas, you can get some very strange structures like lava cones or andesitic shield volcanoes. Low viscosity magmas can also very occasionally produce explosive eruptions with the right conditions, such as Ol Doinyo Lengai in 2007 and 2008. But most silica rich magma will inevitably have trapped gas, so its generally a safe assumption that high silica magma = explosive.
excuse me sir, but you placed volcano map depending of their age, you should have compared with position of the island at each age, then we could all have notice the hot spot theory and understand that these past volcanoes wont wakingup suddenly since they arent anymore on top of magma fill chambere, tectonic is moving 7cm/year to the north-west, so in 60.000years, it moved 4,2kilometer north west since last eruption, isnt it? and in one million year, the big island will move 70km north west and will probably have flank sliding, and another new island would replace it.
It takes a loonnnngggg time for the volcanoes to become completely disconnected from the hot spot, though. Haleakala's summit is 40-50 miles farther from the hotspot than Kohala's and it has erupted only a few hundred years ago with several eruptions in the few hundred years before that, for example. There even appeared to be an eruption of a seamount between Oahu and Kauai in the 1950s.
Trying to catch up, and boy have I got a lot to catch up on, now! Wow! Anyway, leaving a like and comment for each one, to help with that Almighty Algorithm that constantly demands to be fed.
Feels Xmas-y on GeologyHub lately -- as a HI resident seeing consecutive episodes on my home state's geology! Kohala's rarely talked about colloquially re: geology or volcanism, so loved the usual GH concise, easy-to-digest-for-laymen breakdown. Love it -- Aloha and looking forward to next EP, HI-based or not! 👍🌺
I find the geological history of the Hawaiian islands fascinating. Especially when you look at the Northwestern Hawaiian islands and then the remnants undersea. It’s cool. I know it’s a huge topic and I don’t know if you did it already, but it would be an idea. Thanks.
On the topic of giant slides, I’d like to hear more about the Akila slides and the megatsuamis they may have caused, alongside the recent research into megatsunami deposits found around Hawaii. Keep up the great work !
The Kohala slide left a humongous underwater debris field that extends for tens of miles!
While you're doing a series on Hawaii, I'd like to see a video on the Mahukona volcano. I've stayed right there beside it several times and had no idea it was there until seeing this video. The Big Island is one of my favorite places to visit and its geology is fascinating.
It is interesting how far Kohala is from Maui when the volcanoes that followed Kohala are all overlapping without ocean in between.
Also interesting that Haleakala (on Maui) erupted so much more recently than Kohala (on Hawaii). Is that contrary to what would be expected from the direction of the plate sliding over the hot spot?
@@bruceching4078 That is interesting. When did Haleakala last erupt?
@@mikentx57 In the 1400s CE IIRC
@@bruceching4078 True, and it's even erupted more recently than Mauna Kea which is far closer to the hot spot. But I think I remember Geology Hub making a video about eruptions on Oahu or nearby offshore still being a possibility!
@@stonew1927 Oahu eruptions are still possible?? That's wild.
Please do a video on the Moloka'i Ancient Colossal Landslide! I loved your video on the Oahu Landslide! 👍
Thank you for your highly informative and interesting videos. Several years ago we visited the summit of Kohala on our quest to visit all the Hawaiian (Big Island) volcanoes. It was a real challenge. Unlike other summits it is overgrown with a dense jungle.
Also I believe that deep east facing valleys are results of accelerated erosion of cliffs after the partial collapse/slide of the island.
Another interesting point - Mauna Kea grew on the flank of Kohala and so was helped to reach its spectacular height.
There's a saddle between MK and the Kohala mountains/volcano (where Waimea is). I live on MK along the Hamakua Coast and I wouldn't necessarily attribute MK's height to having "grown on the flanks of Kohala" especially when you consider MK's topography extending far deeper and many miles further underwater. Mauna Loa is also near the same height as MK and is further from Kohala. Btw, MK at one point was over 16,000 ft. It has diminished through its sheer weight and erosional processes.
So funny that you're doing these Hawaii videos right at this moment, along with several other unrelated content creators I follow also covering Hawaii... I just got back from a lengthy camping/exploration/geology trip out in Hawaii and have never been there before. I'll call that serendipity.
Posting a video of my adventures in the next couple weeks for those who are interested. Got some great footage of Kilaheua's lava lake and up close footage with manta rays!
Good timing for me, too, as I just got back from there on Wednesday. It was just a 6-day trip for me this time, though.
Subscribed so I get notification when you upload the Hawaii video.
Don't feel bad 5th volcano, I'm ignored too.
I want to say how much I appreciate your subscribers comments answering questions intelligently. 👍 😊
Thank you for this video! Very interesting and informative.
I always learn about new things about how planet Earth behaves from your great videos. The slump into the sea of that huge piece of the new island must have created an enormous tsunami. The resulting deep valleys are astonishing to see. Thank you so much for yet another terrific presentation.
Now we need a video on Māhukona.
I wonder whether the process that caused the 1955 eruption near Necker Island, or the fairly recent activity on East Maui, could one day trigger activity again at Kohala?
Haleakala on Maui is still in its post shield building, which is a stage of volcanism pre-rejuvenation. The forces still involved on Maui have long since died out in Kohala. If the 1955 eruption near Necker Island did in fact take place, it isn’t quite clear whether it was related to the Hawaiian hotspot / previously thought to be extinct shield volcanoes or, the theory I believe in, that it’s related to a secondary submarine range that the hotspot intermingles with.
Very nice, I lived on that volcano for years and explored its densely forested slopes.
Could you do a video on the New Madrid fault system.
The shape and general character of Kohala reminds me a lot more of the Azores than the other Hawaiian volcanoes. Maybe its the fact that its rift is remarkably linear, or the cinder cones on top, or that nice rich green around it, but it just gives off that vibe. Seems like a nice place.
The Northern Coast of Kohala is a beautiful place indeed. No roads through there, but a cool place to hike or see from a helicopter or boat. The lookout over the Palolu Valley and the trail down into it have awesome views.
I think it would be interesting if you made a video going into detail about the life cycle of Hawaiian and other similar shield volcanoes and how/why they progress through different stages
I would appreciate examining the eruptive history of Oahu especially its renewed Holocene activity
Groovy. I used to live in Hawi. Looks like Ohana Pizza was right on top of that fault line. Our house would shake.
Aloha Kohala!
Thank you 🙏
I have been watching very frequent, (Strombolian?) eruptions of Fuego in Guatemala. The camera is not very good, but the eruptions are beautiful and frequent. Have I missed your coverage of this volcano?
Can you please talk about the history of Mt. Taranaki in New Zealand? Thank you in advance.
@geologyhub Can you comment on the history of the very large Cinder cones on the summit?
You should cover the non-extinct volcano on the next island, Maui.
Can you make a video about Haleakela? I'm interested in Maui's potentially active volcano.
Can you do a piece on long valley? When I drive north to the islands valet, it’s filled with rugged cinderblocks, I’m curious as to how that all farmed.
Here’s an interesting topic, you should talk about Aconcagua’s volcanic past and why it is not considered a volcano today.
How do they know that this volcano is extinct vs merely dormant, like Mt McLoughlin? Always been curious.
Similar to how we see if a living thing is alive. Are there Signs of Life? Is there activity under the surface? Is there any seismic activity beneath it? Are there any fumaroles or gas vents? Etc
@BlackCell22 It could still be active as koolau much further away has erupted more recently than kohala and hawaiian volcanoes can go hundreds of thousands of years without erupt Any eruption at kohala won't be happening for a long time since a rejuvenation stage takes ages to happen
It's hard to know for absolutely certain but it has been in decline for a very long time, and as they decline eruptions become less and less frequent. Most volcanoes based on the official global volcanism program are declared extinct after the pass the >10,000 years since last eruption, although that isn't always neccesarily true as activity can persist far longer than that as there are many even older volcanoes that still have earthquakes and active fumaroles despite not erupting for even longer than 60,000 years.
However the odds of an eruption from Kohala are so low they are nearly non-existent and likely several millenia in the far future in that case, Hawaiian volcanoes are quite well studied in all their stages of life and Kohala is therefore judged to be of minimal threat. You can read more about the stages of life here en.wikipedia.org/wiki/Evolution_of_Hawaiian_volcanoes
Would love to see a video on Hyalite Canyon south of Bozeman, MT. The main trail winds through hexagonal columns,(see Palisade Falls), ancient lahars and ahah flows. Hyalite drainage is named for the fact it is one of the few locations in the world that you can find hyalite opal just below Hyalite Peak, some even with play of color
Nice
What defines each of these as distinct volcanoes despite being from the same hotspot and island? Do they each have their own magma chamber?
Magma chambers, different magma compositions, etc.
I have driven the road from Havi to Wiamea many times and you drive right through parts of the volcano. In the right weather it is a beautiful sight to behold. It is very green most of the year. I believe Kohala means whale or whale hill in Hawaiian.
Yes, it's a beautiful drive! What amazes me is that you can still see cinder cones on the flanks of the volcano even after 60,000 years.
The island of Maui in Hawaii also has an active volcano. The are a series of proclastic cones. Maui is a separate island but it is not far away from the big island of Hawaii. Maui does have a fairly large settlement called Kahului.
Haleakala is classified as dormant.
It is actually active according to some sources & even Geology Hub but the information could be outdated.
@@bruceching4078 Wrong. Having erupted at least 10 times in the last 1000 years, Haleakela is classified as active by the USGS, even though many people consider it dormant.
@@stonew1927 Any idea of why USGS says it's active? It hasn't displayed characteristics of activity such as earthquake swarms.
@Bruce Ching It can still be active. It still has fairly young lava flows & the reason why they are no earthquake swarms could be the volcano is not showing any signs of erupting in near future but it is still active because it has erupted many times in the last 10,000 years but it is not showing any signs of erupting soon but it still has the capability of erupting again still.
Can you please do a video on Mauna Loa and Kilauea in the future?
There have been several recent videos on this channel covering both of those, though more are always welcomed! There were several videos a couple of months ago when Mauna Loa erupted and also when Kilauea's eruption resumed following its brief pause after Mauna Loa stopped.
It looks like that north rift zone goes right through my yard…yikes!
Best weather in the world😎
Several people got good videos of a large land slide in San Diego where as section of the local cliffs collapsed. This might make a good topic, also recording a land slide from the business end seems sporting.
Is it possible that the rapidly moving magnetic poles could shift the stresses on the crust causing the Hilina Slump to slide?
Hi, CJ. 👋🏻
Is the Hawaii slump and the giant Crack the same
So, this will probably sound like a pretty stupid question, but wondering... How do we know these are 5 distinct volcanos and not just 'offshoots' from one much larger volcano? I mean, couldn't the five volcanos be getting their lava from the same opening in the mantal without us really being able to tell? I can understand calling each of the openings a different mound/mountain/lava dome, but how can we know for sure they aren't all part of one large volcano, sending material up from the core in different weak spots in the crust? If it's too stupid of a question, please ignore and apologies...
The only stupid question is the one unasked. I do hope Geology Hub will answer this question.
When is a volcano a volcano, and not a vent of another volcano?
The Big Island volcanoes each have their own magma plumbing, unique chemistry, and individual behavior. If they were just five vents of one volcano they would be much more similar to each other.
@@nortyfinerexactly. Magma composition wouldn’t be as disparate as it is across the volcanoes.
This question is far from stupid, and gets to the heart of what makes volcanism so interesting. Mauna Loa and Kilauea are a great example: for many years, geologists though Kilauea was likely a particularly large vent off of Mauna Loa.
An even more interesting case is the Taupo Volcanic Zone. In many ways, it behaves like one gargantuan volcanic field with a nasty habit for large calderas, but at the same time there are distinct volcanic systems within it with fairly unique behavior. It feels like its almost right on the borderline between being one or many volcanoes.
Is the lohi? seamount not considered part of the Hawaii big island?
Correct. Also goes by the name Kamaʻehuakanaloa seamount now
It isn't considered part of the Big Island because it's not above water and not connected to the Big Island by land. If/when it rises above the ocean surface and becomes connected by land to Mauna Loa and/or Kilauea, then it would become part of the Big Island. But that almost certainly won't happen anywhere remotely close to any of our lifetimes.
Oh wow, i didn't know that volcanoes on the big island did build lava domes or really do more than mildly explosive eruptions.
I love residing here in Hawaii, it’s a wonderful place to live.
However, living in paradise does come with it’s own dangers, erupting volcanoes, tsunamis and hurricanes.
I read a story a few years ago about a erupting submarine volcano between Kauai and Oahu spotted by some US Navy pilots and some airline pilots in either 1956 or 1958, can’t remember which?
Living at the base of a volcano, I just pray that nothing happens in my lifetime. I know that the whole state of Hawaii could be on top of a hot zone if magma should make it’s move. 🤣😂🤣
Yeah, I'm pretty sure I've seen a video here on UA-cam about that submarine eruption between Oahu and Kauai. I think it was either on this channel or on The History Guy, but I forget which.
You must be on the big island right now with all the big i vids. Find me ill take you on a hike into the valleys pololu side
I'm not quite willing to write off a volcano as "extinct" when it's so close to 4 that are active, and not far from another (Haleakala) which has a tiny but non-zero chance of waking up in the future. This same channel did a video on Easter Island a year ago, which hasn't had a documented eruption in 10,000 years: the youngest rocks of its Rano Kau volcano are roughly 120,000 years old, but it is still considered active, as is its neighbor Terevaka. Easter Island is a totally different hot spot system, but the setup (three volcanoes in close proximity, two considered active with one "extinct") is similar to the Big Island. This makes me ask, how much do we actually know about Kohala's underground plumbing and its relationship to the plumbing of the known active Hawaiian giants?
With Haleakala's most recent eruption being only a few hundred years ago, I wouldn't call it a tiny chance of re-awakening at all. With 10 known eruptions in the last 1,000 years, it seems like actually quite a large chance that it will eventually erupt again, though it probably won't ever be as active as Kilauea or Mauna Loa again. And, for what it's worth, while it's on a different island, Kohala is actually quite close to Haleakala. The channel between them is less than 30 miles wide. You can easily see one from the other on a clear day. Whereas it's about 55 miles from Kohala to Kilauea and only slightly less than that from Kohala to the summit of Mauna Loa (though, of course, Mauna Loa is huge and the Northwestern-most flows from it are only a few miles from Kohala.)
I still only consider a volcano extinct if it goes 100,000 years without erupting. I do think they should use ground penetrating radar to see if any magma is left underneath the volcano before declaring it’s extinct.
I don't think remaining magma is neccesarily a good way to judge, many old volcanoes still have magma left that cools and hardens in their chambers after they have become extinct, it's one of the way ancient volcanoes are discovered as the hardened magma chamber erodes at a different rate from the outside of volcano and you get for example volcanic plugs left after the rest of the mountain has eroded away.
The big key I think would be if Kohala could receive a small batch of fresh lava that may either erupt independently as a new cinder cone or remobilize some of the old stale magma into for example a lava dome eruption. However with the low rate of eruptions and long time spent it is unlikely Kohala receives much if any fresh lava from the hotspot. It's far likelier that any other volcano on big island or even Haleakala on Maui would erupt rather than Kohala
@@Arthion I’m talking about having a magma chamber that could still have a eruption. I know magma will be in it a long time until it cools. We have the technology now to know if there’s still enough magma underneath a volcano for it to erupt again.
@@bigrooster6893 I mean the quantity isn't so much the big deal as the state of the magma in it, if it is too stale and hardened or molten enough. If it has sat there for 60k + years it's unlikely to change unless you add fresh stuff to the mix.
So explosive eruptions need a gas rich magma not just viscous high silica magma to form a plug, have I got that right?
Yes, even silica rich magmas like dacite and rhyolite "only" for lava flows and domes if there isn't enough gas to turn the eruption explosive.
Yup, in the rare cases that you have high eruptive rates of viscous magma without much gas, you can get some very strange structures like lava cones or andesitic shield volcanoes. Low viscosity magmas can also very occasionally produce explosive eruptions with the right conditions, such as Ol Doinyo Lengai in 2007 and 2008. But most silica rich magma will inevitably have trapped gas, so its generally a safe assumption that high silica magma = explosive.
How about EMI Koussi in Chad. 👍
Where did all the basalt come from if there was no volcano I do believe it was a rift Zone
how do we know that the kohala volcano is truly extinct and not just in long dormancy?
So, if I were to win a very large lottery, you’re implying that the Kohala area would be a good stable area to buy island real estate?
excuse me sir, but you placed volcano map depending of their age, you should have compared with position of the island at each age, then we could all have notice the hot spot theory and understand that these past volcanoes wont wakingup suddenly since they arent anymore on top of magma fill chambere,
tectonic is moving 7cm/year to the north-west, so in 60.000years, it moved 4,2kilometer north west since last eruption, isnt it? and in one million year, the big island will move 70km north west and will probably have flank sliding, and another new island would replace it.
It takes a loonnnngggg time for the volcanoes to become completely disconnected from the hot spot, though. Haleakala's summit is 40-50 miles farther from the hotspot than Kohala's and it has erupted only a few hundred years ago with several eruptions in the few hundred years before that, for example. There even appeared to be an eruption of a seamount between Oahu and Kauai in the 1950s.
Puu Olai on Maui
Trying to catch up, and boy have I got a lot to catch up on, now! Wow! Anyway, leaving a like and comment for each one, to help with that Almighty Algorithm that constantly demands to be fed.
Wow, I wonder if there is evidence of a tsunami from that landslide into the sea?
Kea pronounced “ cay ah “. Rather than “ key ah “.
Kohala is NOT extinct!!! … jessh get your facts straight … you still do not pronounce Maunakea correctly … NOT a “geology” hub!
The area around Kohala is arguably the most beautiful on the whole island
SUCH A LARGE LANDSLIDE WOULD HAVE CREATED A TSUNAMI, BUT YOU DONT MENTION IT