Supervolcano beneath Yellowstone update: Caldera Volcano shocks researchers

This is common in any area that is geologically active. And such things have been happening in Yellowstone for decades that we know of.

This is especially seen at the Mammoth Terraces Hot Springs. I remember going there in 1973, and again in 1977. My parents had some old movie film of the terraces from around 1962. And even by 1977 they knew the feature was moving. Today it is almost 100 meters from where it was the last time I was there. The older ones are now "dead", and what tourists see are mostly new ones built up in the last several decades.

And such events like these will continue until the caldera finally "blows it's top". And that may be next year, or in another 5,000 years.

 

True. And, there certainly are scientists who say an erruption could be far less than the maximum that is thought to be possible.

One can see the hot spot trail caused by tectonic plate movement across Idaho from highways in the area. Flying over it at low altitude is amazing.

Maybe all the ash washed away to somewhere, but the lava is in areas that are quite level and I don't see ash within the cavaties in the lawa.

 

You do not get much ash immediately around where such a caldera erupts. It is blown far away. But if you know what to look for, the evidence is obvious.

And the "trail" is damned near impossible to miss! It originated in the Idaho-Oregon-Nevada border area, and after moving North turned almost due East. Almost the entire Snake River Valley is laying in the older remains of what is now the Yellowstone Caldera. But the hot spot did not move at all, it is the North American Plate that is moving above it. It is known to be over 16 million years old, and they are even suspecting older calderas in Western Nevada are connected.

As for why there is less ash found, that is because of the other geology and geologic history.

Most of the region is covered in layer upon layer of flood basalt. The entire Snake River Plain is built upon almost 2 kilometers of basalt. And this basalt ranges in age from 6 to 15 million years old, so it completely covers the evidence of older eruptions (by 6 mya, the hot spot was sitting about 150 miles West of where it is today).



When I used to do a lot of fossil collecting, it was primarily in the regions in and between the 15-13 (Owyhee-Humboldt event) and 12-10 (Bruneau-Jarbridge event) million year spots on the map. The 15-13 area is very interesting geologically, lots of collapsed caldera that are visible to the naked eye and pumice and ash. The 12-10 region was great for wood and fish fossils, being part of an ancient lake that had been "destroyed" in one of those events (somewhere from 5-12 mya). The 12-10 mya region was particularly rich, especially in what is known as the "Bruneau Woodpile".

But as to the effects of the eruption, we simply do not have enough information on how a "supervolcano" acts. Is it several small eruptions with a single massive one that does the majority of damage, then peters off and becomes dormant again? This is what we know of the most recent such event, Mount Tambora in 1815. The actual "eruption" started on 5 April, with the main eruption itself on 11 April. Which was followed by smaller eruptions and steam releases for the next 3 years until it settled into dormancy again.

Or would it follow the pattern of a Hawaiian or Icelandic volcano? Where it has eruption after eruption until a major one that happens empties the magma chamber and causes the caldera collapse? The geological record is simply not precise enough to know which way such an event would go.

Then you have the truly frightening thing that may accompany such an event, flood basalt. These are massive volcanic events which cover tens or even thousands of square kilometers in layers of lava hundreds of feet thick. The Owyhee-Humboldt event caused the Columbia River Basalt event to start, which covered over 160,000 square kilometers of Oregon-Idaho-Washington to be covered with a thick layer of volcanic basalt.

One of the most well known is the Siberian Traps, over 7 million square kilometers of flood basalt laid around 250 mya. And we have not had such an event in 10 million years. If such was to be triggered again, it would likely cause more devastation than the supervolcano itself. At least 8 global extinction events have been timed to coinciding with flood basalt events.

But you are right in talking about the visual evidence. The entire Snake and Boise River Basins are covered with cinder cones, and benches and fracture zones where one layer of basalt has dropped below another (usually through erosion).

 

Nuc it for science!


Set up lots of monitors to record the event.
And maybe charge for coverage, like PPV.
What's the worst that could happen?

 

Very interesting indeed!

Thank you for this!