More than a thousand small earthquakes have rocked the southern Italian region around the Campi Flegre volcano in recent months, raising fears it may soon erupt after nearly five centuries. Scientists have, for decades, documented similar small earthquakes and landslide events at the Long Valley Caldera, a volcano near Mammoth Mountain in eastern California 6,000 miles away.
Residents watched as a volcano erupted near Iceland’s capital, Reykjavik.
Most experts say neither Long Valley nor Campy Flegre are in danger of erupting right now. Both volcanoes are actually calderas, wide depressions created by powerful „super-eruptions” long ago. Calderas are more difficult to predict than the massive, mountainous structures that most people associate with volcanoes.
when Seismic activity A volcano may indicate that it is about to erupt, and the whole story is very nuanced.
Supervolcanoes, defined as volcanoes that have erupted more than 240 cubic miles at a time, include Campi Flegre and the Long Valley caldera. While Campi Flegrei and Long Valley are potential for massive eruptions, the term „supervolcano” is misleading, said Michael Boland, a geophysicist at the US Geological Survey and director of the Yellowstone Volcano Observatory, according to an NBC News report.
Campi Flegrei last erupted in 1538, and one of the largest eruptions in the system occurred about 39,000 years ago.
Because calderas are large depressions on top of massive magmatic systems, they are often challenging to understand. For example, Campi Flegrei spans seven to nine miles. California’s Long Valley caldera is about ten miles wide.
Seismic activity in the Long Valley caldera has been rumbling for decades and even had a spike in the 1980s, and scientists are generally not concerned about a significant eruption in the near future. This is because the magma underneath is showing signs of cooling.
While it’s impossible to completely rule out an eruption, researchers have discovered that the magma chamber at Long Valley Caldera is actually sealed in a solid rock formation that prevents large eruptions from occurring.