Supervolcanoes Erupt In Incredibly Short Times

The largest volcanoes on our planet, known as supervolcanoes, which can spew out enough superheated gas, ash, and rock to destroy civilizations, have been found to have an incredibly short gestation time.

Previously, it was thought that these supervolcanoes could take as much as 200,000 years to develop and erupt out their molten rock. New research, however, shows that this process can take as little as 500 years.

"Our study suggests that when these exceptionally large magma pools form they are ephemeral and cannot exist very long without erupting," said Guilherme Gualda, director of the study and the assistant professor of earth and environmental sciences at Vanderbilt University.

These supereruptions can have catastrophic effects. They release thousands of cubic kilometers of debris which is 100 times greater than any recorded eruption during our history. It is thought that the Lake Toba eruption in Indonesia 70,000 nearly wiped out the entire human species.

The team gathered and studied samples from the supervolcano site of Long Valley in California. The eruption there took place around 760,000 years ago, and would have covered most of North America in ash.

Usually, supervolcano sites are studied by aging the radioactive elements in a crystal known as zircon. In the beginning, the pools of magma are almost purely liquid with few crystals. The crystals form as the pool develops, and stop forming before eruption. By looking at the age of the crystals, scientists can estimate the time from the formation of the magma pool to when it erupted.

In this case, the scientists chose to study quartz. The results showed that the quartz usually formed between 500 and 3,000 years.

"The fact that the process of magma body formation occurs in historical time, instead of geological time, completely changes the nature of the problem," said Gualda.

There are no current pools of magma that scientists believe are in danger of becoming supervolcano sites, but the findings show that careful monitoring is needed to give advance warning of such an imminent doom.