A massive supervolcano lies beneath Yellowstone National Park.
A supervolcano is defined as a volcano that ejects more than one trillion tons of material when it erupts. When one explodes, it can cover an entire continent in ash. This type of explosion is about 30 times stronger than the strongest volcanic eruption in recent history, which occurred in Krakatoa.
The last time a supervolcano erupted was in Toba, Sumatra, about 71,000 years ago. The ash obscured the sun’s rays and humanity likely came close to extinction. Anthropologists estimate that only about 5,000 humans survived to reproduce after this event.
The prehistoric eruption of the Toba supervolcano nearly wiped out the human species.
Another famous one is located just below Yellowstone National Park in the United States. The caldera, a depression at the top of the volcano, is 25 to 31 miles (40 to 50 km) long, about 12.4 miles (20 km) wide, and about 6.2 miles (10 km) thick. . It’s so big that it’s visible from space. This volcano is believed to explode about once every 600,000 years, but it last exploded over 630,000 years ago.
A supervolcano ejects more than a trillion tons of material during its eruption.
A supervolcano will send hundreds of cubic miles (where about 240 cubic miles is equal to 1,000 cubic km) of ash into the atmosphere, changing the climate for hundreds to thousands of years. When Yellowstone last blew up, a bundle of fossilized rhinos was discovered 621 miles (1,000 km) away from the blast zone, where they suffocated under the heavy ash. These massive volcanoes are the most powerful destructive force known on the planet, and only asteroids or other cosmic events are potentially powerful enough to exceed their magnitude.
The volcanic eruption on Krakatoa in 1883 pales in comparison to the potential of a supervolcano.
The difference between regular volcanoes and supervolcanoes is in the way the magma beneath each one comes to the surface. In a normal volcano, a thin magma chamber leads to a very tall cone, with a relatively thin layer of rock protecting it from the surface. When the pressure from below builds up enough, magma is fired upwards.
In a supervolcano, magma comes close to the surface, but a large mass of rock prevents it from breaking free. This rock forms the top of a large depression called a caldera. Over hundreds of thousands of years, magma from below accumulates in a huge lake of tremendous pressure immediately below the caldera. When that pressure reaches a critical threshold, it blows everything up very high, ejecting huge amounts of molten lava.