| The "Yellowstone Supervolcano" is not going to blow up in 2012 |
| Yellowstone Calderas |
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| USGS map of the overlapping calderas of Yellowstone |
The Yellowstone volcanic caldera is not going to erupt in 2012, and certainly not as a super-volcano eruption.
Introduction
Yellowstone National Park was founded as a park in 18721, and it was named after yellow sandstones along the banks of the Yellowstone River. Yellowstone National Park is a natural beauty featuring many hydrothermal features such as “Old Faithful”. Yellowstone National Park was created from three volcanic eruptions fitting the loose definition of a super-volcano,2.
Mantle Hotspot History
Yellowstone Super-volcano’s fuel has not always been beneath Yellowstone National Park. The mantle hotspot has left a trail of eruptions from its present position under Yellowstone National Park to the Nevada-Oregon State borders (as seen in the image above) dating as far back as 16.5 million years ago. This is due to the movement of the North American Plate to its present location. In its past, the Yellowstone super-volcano has erupted on smaller scales through rhyolitic melts, producing 40 lava flow eruptions. Rhyolitic/rhyolite melts (also known as felsic melts) are the most viscous lava and the most explosive due to its ability to trap large quantities of gases in and around the Yellowstone caldera. The last rhyolitic eruption took place 70,000 years ago, and there have also been up to 40 basaltic vents outside the Yellowstone caldera.
Yellowstone Super-volcano one of many
Yellowstone National Park was not the only volcanic epicenter to experience an eruption large enough to be classified as a super-volcano. The term "Super-Volcano" is not a scientific term, and there is no defining characteristic of a 'super-volcano' eruption, other than the amount of ejected material.3
Yellowstone Super-volcano’s future activity
Scientists are not convinced that there will ever be another supervolcano eruption in the Yellowstone caldera. Catastrophic geologic events are neither predictable nor regular4. The chances of another supervolcano eruption at Yellowstone are exceedingly small for the next few thousand years.
Is Yellowstone Overdue for Another Caldera-Forming Eruption?
No. There have been three of these eruptions in Yellowstone's history, giving us only two intervals between the so-called supereruptions. The intervals between eruptions were 800,000 years and 660,000 years. A valid average cannot be calculated from only two widely separated values.
If we were to consider an average of the two intervals as valid, that would give us 730,000 years between caldera-forming eruptions. Subtracting the 640,000 years since the last such eruption gives us 90,000 years from now.
If we were to ignore the longer of these intervals and consider only the 660,000 interval, that would still leave us about 20,000 years away from considering Yellowstone due for another such eruption, if another should ever occur.
Geologically active area
Proponents of an eruption to occur in 2012 point to recent activity, and claim that the caldera is heating up. In fact, a review of scientific papers <insert citation here> fails to show a consensus among vulcanologists as to whether the magma chamber is filling and heating up, or gradually emptying
Yellowstone is Calm
In an article on BigThink.com, Erik Klemetti summarizes the hoopla surrounding the Yellowstone Caldera:
Yellowstone is pretty calm as giant caldera systems go.
and
Yellowstone is also well-wired to see all the real time data, including earthquakes in the region and in the park, temperatures of hot springs, webcams, deformation within the caldera and hydrologic changes in the area. You would expect that if Yellowstone were headed towards an eruption, we would see lots of rapid inflation, lots of constant seismicity that gets shallower through time, a change in the temperature/composition of the hydrothermal systems and possibly even cracks forming in the land around the caldera. In other words, there will be lots of signs. So, the next time you see a doomdays article about Yellowstone, remember, calderas are busy places and the media loves its disasters.5
Conclusion
There is no reason to think that Yellowstone is going to erupt any time soon. There is no reason to think that if it does erupt again, that it will be a 'Super-Volcano' eruption
