Posted on 12/22/2016 7:41:58 PM PST by JimSEA
Oh, you can. The cone is just in the way.
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Yes, but the plug is what causes the pressure to build up to allow the super explosion. Besides, the cone provides a large percentage of the projecta (i.e. ash).
The Yellowstone Caldera says your suspicions are incorrect.
Typically, Caldera eruptions start with a collapse. .
An eruption would be CAUSED by Global Warming.
believe what happens is after the eruption empties the magma chamber below the erupting volcano, the roof of the magma chamber collapses,forming a caldera.
Bush’s fault err no Trumps fault, global warming err global cooling, fake news??
Nope. The Magma chamber expands to the point that the overlying rock fails mechanically, collapsing into the chamber and causing explosive venting. . .
the magma chamber/reservoir is like a soda mix, but the gas level is way higher because the medium (molten rock) is so much denser. Additionally, the added pressure of depth allows more to be entrained.
Recall the article mentioning the area shares a common magma source with Vesuvius ~ 20 miles away? Now imagine that a large area of the land between those two areas thinned and stressed a bunch over the magma chamber at the same time as the chamber got a good recharge of extra gas rich magma and a significant fraction of it blew out. That’s “supervolcano”.
Mt St. Helens was something like 0.8 cubic mile of ejected material with a portion of it being the cone blowing out. They’re saying here this was previously in the 50 cubic mile range (rough conversion from km).
Check this out to get an idea of how unstable gas entrained magma is and how little it takes to set it off. It’s a bag of garbage penetrating the crust on the crater lake of lava.
If it erupts on Jan 20, 2017, it will be Trump’s fault; and maybe a little bit of Bush’s as well.
How do you get a collapse with a structure to collapse? The two biggest examples we have are Krakatoa & Mount Tambora, both of which had major edifices before the explosions.
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