What it tells us is that an eruption can happen a lot sooner and also
be smaller. In fact it appears probable as the original super
eruption put so much material out and created a huge caldera.
What we do not have is a sense of time. A cubic mile per year for
six thousand years will look quite the same in geologic record when
compared to six thousand cubic miles in one year. One gives us
extinction while the other makes us annoyed.
On that basis, Hawaii could be an active super volcano, and
certainly, Iceland must be a super volcano.
All this informs us that the total volume can be seriously
misleading. The big events have happened and have been destructive.
However, they have not driven life to extinction except locally and
rarely.
The Next
Yellowstone Supereruption Is Closer Than You Think
The good news:
scientists have discovered that "the
Yellowstone super-volcano is a little less super than
previously thought." The bad news: the Yellowstone super-volcano
is "more active than previously thought." That means
eruptions are more frequent. So the next one is likely closer than
previously predicted. Gulp.
According to the the
researchers from Washington State University and the Scottish
Universities Environmental Research Centre, the next eruption may not
wipe out half of the United States, covering the rest in 3 feet of
ash and pushing the world into hundreds of years of nuclear winter,
challenging human civilization to a game of death and survival.
That's what a previous study from the journal Earth and
Planetary Science Letters posited. Again, very good news.
But on the other hand,
as Ben Ellis—a post-doctoral researcher at Washington State
University's School of the Environment and co-author of this most
recent study—says: "the Yellowstone volcano's previous
behavior is the best guide of what it will do in the future. This
research suggests explosive volcanism from Yellowstone is more
frequent than previously thought."
Multiple eruptions
Their new research
shows that what scientists thought was Yellowstone's biggest
eruption, the origin of the the 2 million year old Huckleberry Ridge
deposit, was actually two eruptions 6,000 years apart from each
other. They used a new high-precision argon isotope dating technique
to find this difference. This technology, says co-author Darren Mark,
is "like getting a sharper lens on a camera. It allows us to see
the world more clearly."
The result is that the
first eruption that created Huckleberry Ridge was "only"
2,200 cubic kilometers, roughly 12 percent less than what geologists
thought. Then a second eruption happened 6,000 years later, adding
the remaining 290 cubic kilometers.
For comparison, Mount
St. Helens produced 1 cubic kilometer of ash in its 1980 eruption.
And the latest comparable eruption registered in the United States
were the 116 cubic kilometers of ash produced by Mount Mazama in
Oregon, 6,850 years ago.
Somehow, the idea of
the Yellowstone super-volcano eruption being 12-percent less powerful
than previously thought but more frequent doesn't make me feel much
better.
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