The past few years, we’ve been subjected to gloom and doom predictions that frighten many people. There are the usual Armageddon and end of the World prophesies that pop up from time to time. There was the silliness about the Mayan calendar. And who could forget the Millenium madness of 1999?
These type of predictions have been based upon arbitrary beliefs about how certain numbers and dates have some sort of “power” over our part of the Universe or our Galaxy, or some such concept. Basically, they are mental constructs or ideas, that’s all.
However, sometimes a couple of more realistic end of the world scenarios gain traction in the popular media and cause worry and consternation. First of those is the concern about a large asteroid smashing into our planet. If that should happen, we are told that an epoch ending series of events would quickly unfold. The second worry is about the Yellowstone Caldera and how it’s catastrophic eruption will happen very soon.
The asteroid threat can conceivably be met by technological means, so it appears to be less troublesome. But the Yellowstone threat is something our species is totally powerless to prevent. The worry is, that when, not if, the super-volcano in Northwest Wyoming blows its top, the end of life as we know it is nigh.
Danger that lurks under the crust of the Earth beneath our feet presents an especially insidious menace to our well-being and survival. The last time a friend and I visited Yellowstone National Park, one of the things we took in was the “Yellowstone” movie at the IMAX Theatre near the West Entrance to the park. I felt quite unsettled when the description of the Caldera was explained. To be sitting in an enclosed building situated on top of the World’s largest supervolcano while watching a film about the danger of that same supervolcano can feel mighty scary.
Some concern has been raised since 2004, because there have been observations of several square miles of ground above the caldera rising as high as 7 centimeters per year. Seemingly more troubling is the increase in numbers of earthquake “swarms” at Yellowstone National Park recently. A swarm is a localized sequence of many earthquakes happening in a relatively short period of time.
Until recently, Geophysics professor Bob Smith had never witnessed two simultaneous earthquake swarms throughout his 53-year career around Yellowstone. The latest two swarms occurred last September.
The Yellowstone Caldera has produced catastrophic eruptions three times within the past 2,100,000 years. The last one was about 640,000 years ago. It blew up with a force more than 1,000 times worse than the Mt. St. Helens’ 1980 disaster. The last prehistoric Yellowstone eruption deposited an ash layer, ten feet deep, a thousand miles away from Yellowstone. There is a deposit not far from my home in Northeast Nebraska, at Ashfall Park in Antelope County.
Tabloid reporters and some Internet writers capitalize on the most fearsome aspects of caldera eruptions. Especially fetching comments include, the “potential to end all civilization”. The fears include a spewing out of magma and ash as high as 25 miles into the atmosphere to cause decades long volcanic winters. The superheated ash, gas, and rock is capable of blanketing most of North America. When this happens, it will be impossible to grow crops. Also, mass extinctions will surely occur.
Some geologists now suggest that instead of magma build up lasting thousands of years to time of ruptions, the buildup could possibly take only a few hundred years. One study from Vanderbilt University states that when exceptionally large magma pools, the size of the one beneath Yellowstone, that they cannot exist long without erupting.
Meantime, geologists from the U.S. Geological Survey have stated that while they don’t know exactly when the next eruption of the Yellowstone supervolcano will happen, they do have a reasonable idea about the type of eruption it will likely be.
Most probably will be an hydrothermal eruption of steam and hot water. The result would be shallow craters of about a kilometer across. If there is to be an actual volcanic eruption in Northwestern Wyoming, they might be as strong as the 1991 Mount Pinatubo eruption and include some lava flows.
Least likely is the worst-case scenario that was described earlier in this post. The geologists say the probability of a caldera forming eruption in any given century is extremely low. Scientists are very confident they would notice the signs of a super-eruption by watching the upward movement and accumulations of large quantities of magma just beneath the Earth’s surface.
Right now, none of this is happening.
The Blue Jay of Happiness highly recommends Yellowstone National Park as one of the best vacation destinations you’ll ever find.