by Mason Scher
Before new data was presented in August of this year, geologists expected that the supervolcano lying below Yellowstone National Park would take thousands of years to prepare to erupt, giving America and the rest of the world ample time to prepare. However, according to the New York Times, a graduate student has blown the top off this assumption, showing instead that the supervolcano could ramp up to explode in as little as 10 years.
Each of the more than 3.8 million people who visit Yellowstone National Park every year set foot on a gigantic magma chamber which is responsible for the magnificent geysers that draw so many visitors. This chamber is so large that Yellowstone is dubbed a supervolcano—meaning it has the potential to erupt over 240 cubic miles of magma. Yellowstone is a hotspot volcano, meaning the magma results from a plume deep in the mantle that reaches the continental crust.
According to Dr. Pearsall, a Chemistry professor here at Drew, the magma builds up, reaching pressure high enough to start pushing up the rock above. Once the bulge is large enough, a ring of fractures forms around the base of the bulge. This causes the pressure inside the ring and therefore the magma chamber to drop, which is followed by a major explosive event. The center of the dome collapses into a gigantic caldera, and massive pyroclastic flows ensue. These flows are made of incredibly deadly chunks of rock moving rapidly out from the collapse and also result in huge amounts of ash being ejected into the atmosphere.
This process repeats at Yellowstone about every 700,000 years. The last one occurred about 640,000 years ago, so we’re due for an event in the near future. Geologists track the progression of volcanic activity with incredibly precise GPS measurements which show the bowing of the caldera’s surface. Increased rates of bowing will alert scientists to a more imminent eruption, which would be 2,500 times larger than the eruption of Mt. Saint Helens in 1980 which caused billions of dollars of damage in 11 states. The next Yellowstone supervolcano eruption could result in a cloud of ash over 500 miles wide, covering the western United States, causing significant damage and blocking out the sun, perhaps even affecting global climate.
The wonders of Yellowstone are breathtaking and the danger is real. If you’re interested in following the activity of Yellowstone, visit https://volcanoes.usgs.gov/observatories/yvo/.