Final Warning Oct 2018 Yellowstone Volcano Eruption! Experts Discuss Warning Signs Of Eruption P2March 13, 2019
We’re looking here at a geologic map of Yellowstone National Park and the different colors represent different geologic units different rock types different ages of rocks you can see that all of the pink units in here these represent the very youngest lava flows mostly that erupted at the Yellowstone volcano most of these are between about a hundred and sixty.
And seventy thousand years old and we see that that they’re covering up this area of the park it turns out this is the Yellowstone Caldera it starts around here and it moves.
Out into the area over here and it’s about 50 miles long and it formed when this green material erupted this is called a lot of Creek tuff and the age.
Here in the light green and the dark green also to the south the age is six hundred and forty thousand years this was an enormous eruption and it spread ash over much.
Similar eruption to that today would would certainly be a big deal.
But since this time there have been about 80 different eruptions at Yellowstone some of them are very big this one is the most recent 70,000 years old and it’s called the pitch stone plateau lava flow in fact the size of it is about the size of Washington DC and it’s.
About a hundred yards thick in most places so this is this is what we’re looking at we can see volcanic rocks everywhere evidence that this is a really unusual place it’s a massive volcano some of the.
Eruptions from Yellowstone are truly enormous eruptions some of the largest ones that are known of on earth and that includes this green unit here the lava Creek tuff as well as the purple unit which is the huckleberry Ridge tuff which is erupted 2.1 million years ago so these are some of the largest eruptions that we know of on earth and because they erupted so much material on the order of a thousand cubic kilometers or 250 cubic miles then they get termed as super eruptions really big.
Eruptions and the way that it works this is kind of a.
New terminology and super eruptions if you’ve if you’re a volcano that has exploded and created one of these deposits then you get called a supervolcano and that’s where the.
Word supervolcano comes from so you have this this magma that’s beneath the surface.
And when it erupts and comes out there’s no longer support for the ground surface up here and.
As a result the ground surface just caves in it founders and it falls in you’re left with what’s called a caldera it’s a subsidence or feature or a cave-in feature that’s it’s caused.
When it loses its support of the underground magma as a result when it first formed you had a hole that was.
On the order of 50 miles long and.
Maybe even a thousand or 2,000 or 3,000 feet deep in places.
We have this deep magma chamber and there’s a lot of heat the magma is generally at temperatures like seven eight hundred.
Degrees centigrade or something like twelve for 1300 degrees Fahrenheit there’s a lot of heat that heat heats up the rock and that rock then there’s conductive cooling there’s water down there that water gets heated up and so that much of the water that’s near the surface.