Rangers at Yellowstone National Park are often asked to predict when the next massive volcanic eruption will occur there.
A team of USGS scientists, who surveyed the park’s underground magma reservoirs, recently confirmed the standard response, “probably not any time soon.” But they have pointed out that the area where such activity is likely to occur has shifted, according to a report in the journal Nature.
It’s not like there’s been a pattern of frequent, massive eruptions there; the area has seen only three major events over the past two million years. Those events are labeled “caldera forming,” because the molten rock vacating the underground reservoirs leaves an empty space, which leads to the land above collapsing, ultimately forming a bowl-shaped basin.
Beneath those basins, called “calderas,” sit reservoirs of magma. The recent survey shows that the magma within them has not stood still. It now appears to be shifting ...
