IgneousRocks From , joined Dec 1969, posts, RR:
Reply 2, posted (6 years 9 months 1 week 5 days 8 hours ago) and read 3039 times:
I just finished reading Bill Bryson's "A Short History of Nearly Everything" and he writes a bit about Yellowstone and its potential for an eruption of epic proportions - one that could wipe out living creatures for 100s miles in every direction.
Yellowstone, it turns out, is a supervolcano. It sits on top of an enormous hot spot, a reservoir of molten rock that begins at least 200 kilometres down in the Earth and rises to near the surface, forming what is known as a superplume.
ER757 From Cayman Islands, joined May 2005, 2871 posts, RR: 7
Reply 4, posted (6 years 9 months 1 week 5 days 6 hours ago) and read 2954 times:
Quoting Flighty (Reply 1): There is almost nothing scarier than going to Yellowstone and contemplating what is truly going on down underground.
That's true - but the show above ground is so fascinating that it generally takes my mind off the subterranean plumbing.
Quoting 4holer (Thread starter): Not saying it would be "The Big One", but if I had to guess I'd say that something is about to happen there.
Stuff happens there every day, but I know what you're saying. I am not real familiar with the type of volcano that Yellowstone is. Are smaller eruptions possible, or does it always go ka-boom in a BIG way?
Powercube From United States of America, joined Jul 2007, 265 posts, RR: 1
Reply 5, posted (6 years 9 months 1 week 5 days 4 hours ago) and read 2916 times:
Quoting ER757 (Reply 4): Stuff happens there every day, but I know what you're saying. I am not real familiar with the type of volcano that Yellowstone is. Are smaller eruptions possible, or does it always go ka-boom in a BIG way?
I'm not a geologist, but since there's so much sensationalism out there I thought I should just say a few things. Yellowstone does not erupt only as a caldera volcano- 70000 years ago it erupted in a standard plinian way. Also, quake swarms are not uncommon in the area, in 1985 there was a swarm of more than 1000 quakes towards the Northwestern edge of the caldera and nothing bad seemed to come of it. I would imagine given that the cause the YVO gave at the time was magma moving around there was a fairly constant harmonic tremor going on as well. I'm not sure though, I'm not even sure if what we see here are harmonic tremors. A lot of these quakes are occuring at depths of under 1km, the magma chamber is five miles down. It's also important to note that the seisomography instruments in place are extremely sensitive and there have been very severe winds in the area since the start of this swarm. This does have the potential to create an insane amount of noise on the seismograph and this can confuse things. Another thing I never really understand is where the 600,000 year average comes from, a volcano that never once erupted without more than 700,000 years in between seems like a very hard case to make that we are overdue. If this was the very distant future and more of Yellowstone was bulging more than it is, then I'd be more than a trifle concerned.
Lumberton From United States of America, joined Jul 2005, 4708 posts, RR: 19
Reply 10, posted (6 years 9 months 5 days 7 hours ago) and read 2323 times:
Quoting Slider (Reply 9): So this is essentially a global doomsday scenario. Ah, lovely. Scary stuff, actually.
A super volcano eruption? From what I read and see on the History Channel, definitely. It would pump enough Sulfur Dioxide into the atmosphere to chill the entire planet down a tad for a long, long time.
"When all is said and done, more will be said than done".
Slider From United States of America, joined Feb 2004, 7117 posts, RR: 33
Reply 11, posted (6 years 9 months 5 days 2 hours ago) and read 2267 times:
Quoting Lumberton (Reply 10): A super volcano eruption? From what I read and see on the History Channel, definitely. It would pump enough Sulfur Dioxide into the atmosphere to chill the entire planet down a tad for a long, long time.
Not to mention ash that would cover crops, the food belt of the USA that feeds, oh, a lot of the world.
I don't wish to alarm anyone, but bad made-for-TV movies notwithstanding, it's quite something to get your brain around. Scary.
And to think if I did not have an unhealthy interest in matters geological, I would have missed that gem.
Just as well it is well instrumented (Yellowstone, not the shoes) because extrapolating a few decades records to an over half a million year event is just a bit tricky. Even the much better understood Mt St Helens was tricky to predict until very near the major eruption.
Merapi too is fairly well understood and erupts quite frequently but its last few rumbles have been nearly as much of a mystery as ever. There are plenty of other possible major eruptions. Bandung is about 20 to 30 kms from a volcano that has many features in common with Krakatoa except for the marine setting for Krakatoa!
Nighthawk From UK - Scotland, joined Sep 2001, 5280 posts, RR: 31
Reply 15, posted (6 years 9 months 4 days 15 hours ago) and read 2146 times:
Quoting Cptkrell (Reply 14): January 21, 2012 actually. That is, acording to the Mayans, Chinese, Nostradamus, native American Indians and the History Channel special that I watched last night Smile regrads...jack
21st December 2012 actually, according to the Mayans.