If you are like me, you may have wondered if Japan was yet inhabited by humans in 5284 BC. A quick look at Wikipedia assured me that yes, Japan has been inhabited for at least 30,000 years.
Also well worth noting that we have evidence humans reached Sahul a.k.a. greater Australia between 60,000 and 50,000 years and from study of the water gap barrier that feat even at the lowest sea level extent would have required traveling against the current a distance large enough that the land on the other side would not be visible over the horizon, though the smaller lesser Sunda islands which fill this intermediate zone would have been close enough to be visible to the shore which could have readily facilitated island hopping in a way to cross the deep water boundary zone. Likewise the dates for the colonization of America have been pushed back into the range of greater than 20,000 years when no land bridge would have existed between Beringia & parts of Alaska and other unglaciated parts North America which again would require some form of water based transport likely following the kelp forest belt known to have extended through the region at times in the past. Japan also includes areas along that coast which align with the great kelp forest belt of the Pleistocene which would have provided good conditions for such early coast hugging island hopping seafarers.
@@b.6603 Good possibility though what evidence remains would in part depend on the types of settlements people were using at the time as smaller settlements would likely be harder to find. On that note Tambora has had a really fascinating albeit tragic record of the large scale civilization on Sumbawa which had been buried by its pyroclastic ejecta full of Terraced farms and port cities which preserve trade items from far and wide all of which became buried beneath the eruption deposits.
Thanks as always! The Akahoya eruption would have been very interesting and terrifying to see. Again, similar to Iwo Jima's past caldera forming eruption, I wonder if the eruption column reached the mesosphere, as demonstrated by Hunga Tonga-Hunga Ha'apai. I do agree with your personal classification of Large caldera complexes. Revised eruption volume estimates can be quite crazy. For example, the Youngest Toba Tuff's supereruption's more recent estimates range from 5,600 cubic kilometers to more than 13,200 cubic kilometers! Another example is the Minoan eruption from Thera, which has been revised downwards to a VEI 6, from a VEI 7.
Fascinating account. The process of the eruption…the sound it would make the heat the pyroclastic flows the ash fall the tsunamis the probable earthquakes the backfilling of the magma chamber so much activity on an unimaginable scale. Excellent video.
I did a quick search of events around 7307 years ago. Seems the Earth was emerging from the last glaciation. This is also the time of the quaternary extinction and the loss of megafauna. Also the beginning of the neolithic revolution and the emergence of agriculture.
Was this eruption boosted by the seawater similar to hunga tonga-hunga ha'apai volcano? Would that interaction give you the idea that this is a supervolcano while not really being one?
if that eruption was huge, I can't compute the amount of materials released into the atmosphere. wouldn't there had been climatic changes afterward? could historians and archeologists provide clues?
Every so often you ask if we have any topics we would like to see to comment and ask. Have you ever done a video on Mount Yasor and it's reported 1,500 year long eruption?
@@clover5172 The hunga tonga eruption is only 2 years old so there are still large estimates about the eruption. The 1991 eruption of Pinatubo looks like it was larger in bulk volume but smaller in DRE volume. So far they seem to be essentially the same if we're looking at ejecta volume :)
Can you do videos on the extinct volcano on Garrett Island in the Susquehanna River near Havre de Grace, Maryland as well as the ?craton? ?pluton? Rock formation that is known as sugar loaf mountain, also in Maryland? Also I found volcanic glass (appears to be obsidian) embedded in the dirt in the middle of Baltimore, any idea where it could have come from (found a cluster of it in dirt basically located in downtown Baltimore)?
Using the term "supervolcano" sounds interesting, but now that there are more and more "supervolcanoes" being discovered around the world, it just doesn't seem fun to use the term at this point.
I am a supervolcano with the power of my red lava hear me roar.- Joseph Stalin I was born in Mt Paetku a supervolcano that even USA are very scared of me. -Kim Jong Un
I'd say, any volcano that erupted 300 to 999 km3 of Tephra should be called Supervolcanoes, and those that erupted 1000 km3 and more should have a new classification, maybe Ultravolcano or Destruvolcano or Viovolcano or better Gigachadvolcano.
Well, I believe that any volcano that erupted at least 800 km3 of Tephra should be classified as Supervolcano. Since this volcano along with the two you mentioned have yet to have such eruptions, theyshould not be classified as Supers. But these kind of volcanoes have chances of erupting more than 1000 km3 of Tephra and they'll become True Supervolcanoes, but only time will tell when.
Quick question, I noticed in the chart of the largest eruptions in the last 10k years that Crater Lake is now suddenly second, pushing Kurile Lake down to 4th. When was Crater Lake’s climatic eruption’s tephra estimate changed to 175km^3 and why?
Incredibly rude of this volcano to kill tens of thousands of people and submerge the south of Japan with a metre of ash and tsunamis and wotnot. Very undiplomatic indeed
I noticed in charts magma chambers seem to show rounded..is that always the case..i mean i theory could a magma chamber empty so much it won't collapse..and leave a huge void underground? Or would it naturally just fill up and solidify?
Magma chambers always collapse after huge eruptions as the pressure exerted by the accumulated magma against the rock above rapidly falls below the force of gravity acting on the rocks above during the height of eruptive intensity. In much the same way rising magma and hydrothermal fluids exert pressure on the ground above causing the ground deformation and accompanying earthquakes that almost always occur before eruptions. The flip side is that one can also get elevation loss and earthquakes due to cooling of magma at depth which contracts and hardens thus exerting less pressure on the roof rock above.
hey there! I wonder if you can tell in one of your videos if there is any connection between volcanic activity/eruptions and tidal forces that affect the earth?
regarding to 2:58 when that emptied magma chamber collapses, it seems to me as it displaces huge amounts of material i guess that will cause another huge (series of) tsunami. Is that a correct assumption?
I honestly think that the cutoff for "supereruption" should be 316km^3, since that would technically be a "VEI 7.5" (even though VEI is only whole numbers) cause the way the log scale works halfway between 1 and 10 on a log scale graph is 3.16, and also iirc there's a bit of a gap in eruptions in the mid VEI 7 range. The cutoff of a VEI 8 at 1000km^3 feels ultimately very arbitrary, and I find your classification of some upper end VEI7 eruptions as very inconsistent and confusing. 316km^3 would be a very elegant way to deal with this issue, perhaps the lower end of this scale could have a separate subclassification for the "LCC" style volcanoes.
By the most widely accepted designation of a super volcano, Campi Flegri isnt even close. The accepted requirment is at least one VEI 8 eruption, Campi Flegri's biggest eruption was a VEI 7
we dont need extra terms to denote these volcanos, just call them super. the borders of terms we define will always be a little fuzzy but is no issue to the term itself. imagine if you will we later find a bunch of volcanos that are not quite 'large caldera complexes' but also not 'supervolcano' enough we call them 'super large caldera complexes' yaay. yea no; not needed and only makes it more confusing.
Man, we should have a new classification for true supervolcanoes that erupted 1000 km3 of Tephra, they should be called Gigachadvolcanoes. And Supervolcanoes are the ones that erupted 300 km3 to 999 km3 of Tephra.
Is there a theoretical limit to how high into the atmosphere volcanic material can be ejected? Could an eruption be powerful enough for some material to reach space and not fall back to the ground? If so, are there any known examples where this happened? Thank you.
"Reaching space" is not the same as in orbit. Material blasted straight up, no matter how high, will always come back down. It takes a great deal of horizontal velocity to remain in orbit.
Taupo is considered a supervolcano because it has produced a VEI 8 in the past. In fact, this eruption was the most recent eruption of that magnitude ever documented.
Get over it. Before Common Era (BCE) is standard terminology in historical references. This is because the dating of the NT's main character if uncertain and there is no reason for Christian beliefs to have a hegemony in history.
@TheOriginalDanEdwards grow up = are u into history or the stupid thoughts of kids today = lets face it they are going through more money then their parents ever did. not only that but alot of them are living off their parents
The implications of this eruption, if correct on timing, could have had major impacts to human history, Y chromosome diversity collapse being just one instance.
