The caldera inside Yellowstone National Park gets its nickname as a supervolcano due to its capability to inflict global devastation in the event of a supereruption. Despite such an eruption not occurring in more than 640,000 years, the system is constantly monitored by the United States Geological Survey (USGS) for any changes. The University of Utah’s Professor Robert Smith has been collaborating with the government agency since the Sixties in a bid to gain greater knowledge of Yellowstone’s geology.
He revealed during the ‘Inside USGS’ documentary some of the most significant events that have occurred in furthering scientists’ understanding.
He said: “The occurrence of the Hebgen Lake Earthquake was an epiphany, the discovery of the gigantic uplift of the caldera followed by an earthquake swarm was the same.
“Wow, that was something that really got us tuned in.
“We had an accelerated uplift from 2004 to 2010, it was going up at 25cm.
“While you don’t see it in your footsteps, you know these are rates that are higher and faster than the San Andreas Fault is loading.
“We just discovered that the caldera is now returning back to uplift and it’s going up at 40cm a year.”
Prof Smith went on to explain why they now believe earthquakes are key to releasing the pressure of the supervolcano.
He added in 2015: “So we view this caldera as a living, breathing thing and I argue that all these little earthquake swarms we have are really just relief valves.
“So if we have a lot of swarms, that tells us fluids are squirting out of the magma body and if we keep having swarms and squirting out we’re fine.
READ MORE: Yellowstone volcano: ‘Likely explosions’ at park pinpointed after ‘unstable’ discovery
University of Leicester volcanologist Thomas Knott said in June: “We discovered that deposits previously believed to belong to multiple, smaller eruptions were in fact colossal sheets of volcanic material from two previously unknown supereruptions at about nine and 8.7 million years ago.”
Both of the newly discovered supereruptions occurred during the Miocene, roughly 23 to 5.3 million years ago.
Dr Knott added: ”These two new eruptions bring the total number of recorded Miocene supereruptions at the Yellowstone-Snake River volcanic province to six.”
This means that the recurrence rate of Yellowstone hotspot supereruptions during the Miocene was, on average, once every 500,000 years.