Yellowstone Supereruptions: Activity At Hotspot Waning, Chances Of 'Cataclysmic' Explosion Low

Researchers have discovered two ancient supereruptions associated with the Yellowstone hot spot track.

According to Science Alert, the two new-found events have been named the McMullen Creek eruption (occurring about 8.99 million years ago) and the Grey's Landing eruption (occurring about 8.72 million years ago).

Image For Representation/Twitter

They significantly adjust Yellowstone's long-term volcanic timeline and appear to show that huge eruptions are now occurring way less frequently than they once did.

The research, published earlier this month in the journal Geology, points out two new eruptions that emanated from the Yellowstone supervolcano over the past 9 million years, including one experts believe is the "volcanic province¡¯s largest and most cataclysmic event." The new discoveries suggest the intensity of the hotspot is waning drastically.

¡°It therefore seems that the Yellowstone hotspot has experienced a three-fold decrease in its capacity to produce super-eruption events,¡± said the study's lead study author, Thomas Knott, in a statement. ¡°This is a very significant decline.¡±

Scientists were able to use a combination of chemical, magnetic, and radio-isotopic analysis to link volcanic deposits across tens of thousands of square kilometres (or several thousand square miles), joining together geological records that were previously treated as separate.

The first supereruption, known as the McMullen Creek supereruption impacted a nearly 4,600-square-mile stretch of modern-day Idaho and the second, known as the Grey¡¯s Landing supereruption, impacted nearly 8,900 square miles of Idaho and Nevada.

Reuters

The supereruptions released clouds of searing hot gas and ash at temperatures greater than 900 Celsius that spread at supersonic speed, sterilizing the land surface, according to Thomas Knott, a volcanologist at the The University of Leicester and the paper¡¯s lead author.

The Yellowstone supervolcano has erupted at least 10 times over the past 16 million years, according to Live Science.

With the additional two supereruptions, there are now six that have occurred between 23 million and 5.3 million years ago, with one happening on average every 500,000 years, according to the researchers. The two supereruptions that have occurred since then averaged a span of one every 1.5 million years, indicating a decline.

Knott said this new data raises questions about the lifespan of volcanic hot spots, wondering whether hotspots hit a "midlife crisis" where activity slowly dwindles before their death.

Researchers won't know definitively until the hot spot dies, although Knott said it's almost impossible to predict when that may occur, state reports.