Park rangers at Yellowstone National Park in Wyoming acted quickly to close down a road near Mammoth Hot Springs after a new thermal feature became “visibly active.” By “visibly active,” they mean heat near the surface measuring 152 degrees Fahrenheit and hot water bubbling from holes drilled only 20 inches into the ground. This comes just a few months after geologists discovered a massive, previously unknown Yellowstone magma chamber that could trigger a supervolcano of cataclysmic proportions. People in the area are understandably nervous. Should they be?
A “thermal feature” is a hole in the earth’s crust that emits hot water and steam (called a geyser) or non-water gases and vapors (called fumaroles). Yellowstone National Park is a stunningly beautiful ecosystem but the main attractions are its thermal features.
This new one was discovered in May 2015 on Upper Terrace Drive near Mammoth Hot Springs. Besides the high heat on the surface and hot water emissions, thermal imaging showed activity under the pavement, causing officials to block off the road and adjacent areas until further notice.
What kind of “further notice” might they be waiting for? In April 2015, University of Utah seismologists discovered a reservoir of hot, partly molten rock 12 to 28 miles beneath the Yellowstone supervolcano that is 4.4 times larger than the known magma chamber. That’s enough magma to fill the Grand Canyon 11.2 times.
The Yellowstone supervolcano last erupted 640,000 years ago, devastating what is now North America and most likely affecting the rest of the planet’s climate and life. The resulting caldera has remained inactive ever since. However, in 2003, seismic researchers noticed ground temperatures rising in the park (up to 200 degrees Fahrenheit) to the point where geysers dried up and sap boiled in trees. The park was closed until things literally and figuratively cooled down. Seismologists have been on alert ever since.
Is it time to start digging your supervolcano shelter? The Utah researchers put the odds of an eruption at 1 in 700,000 – a number the National Park Service would certainly modify to protect its millions of annual visitors. Volcanologists say the indicators of a possible supervolcano eruption would be much greater thermal features – like earthquakes, rock-lifting explosions and lava lakes forming.
Meanwhile, as their shoes sizzle and flip-flops fry, residents of Wyoming, Montana and Idaho want to know what happened right before the rocks started flying. Should they be worried? Should we?