Yellowstone is a massive volcano that has erupted in massive fashion many times in its long history. With the knowledge that it can erupt on an enormous scale again in the future, it seems there is a constant state of worry about whether it will wake up and erupt a VEI-8 sized eruption once again.
Is Yellowstone Overdue to Erupt?
Before we go further into why Yellowstone is not overdue to erupt, it’s important to establish something. Fear sells ratings and clicks, hence the old adage “if it bleeds, it leads”. Many news and media sources understand this, and it’s not uncommon for reporting on Yellowstone to mention how it is an “overdue” super-volcano that is going to destroy half the world. Other news sources omit important information, or have a tendency towards a melodramatic tone, and some just have a basic misunderstanding of how volcanoes work. The point is, take Yellowstone news with a grain of salt unless it’s coming from a Geologist or Volcanologist working for the Yellowstone Volcano Observatory.
Eruption Frequency of Yellowstone
It is important to understand that the Yellowstone volcanic system is a part of a hotspot track that the North American crust has been slowly sliding over for over ten million years.
The three VEI-8 eruptions at the current location of Yellowstone occurred:
- 2.1 million years before present – Island Park Caldera
- 1.3 million years before present – Henry’s Fork Caldera
- 630,000 years before present – Yellowstone Caldera
With this knowledge, it’s easy to extrapolate a recurrence interval of approximately 650,000 years between each super eruption. With this extrapolation, one may believe we’re overdue for an eruption, but this really isn’t the case when you learn more about Yellowstone’s extended history. First off, this is a very small sample size, but the more important point, is that Yellowstone has a history that goes far beyond the past three eruptions.
Being a hotspot, there have been many eruptions at locations separate from the current Yellowstone placement, and if you analyze all the super-eruptions (VEI-8 or larger), you get a recurrence interval that is significantly longer than 650,000 years. Also, the Henry Fork caldera eruption that occurred 1.3 million years ago was not a VEI-8 eruption, so by definition, was not a supereruptor.
- Yellowstone Caldera: 640,000 years ago
- Henry’s Fork Caldera: 1.3 million years ago
- Island Park Caldera: 2.1 million years ago
- Kilgore Caldera: 4.45 million years ago
- Blacktail Caldera: 6.62 million years ago
- Castleford Crossing eruption: 8.1 million years ago
Using the additional eruptions listed above, the interval between eruptions raises to approximately 1.4 million years between blasts, which is almost double the initial estimate of 650,000 years. This however is still probably not entirely accurate as there are many more eruptions that have occurred previous to those listed above, although the finer details on older eruptions are not entirely known at this point.
So using what we know, it’s not probably that Yellowstone is overdue.