Extinct volcanoes may not be truly dead - research

extinct volcano/ file: Universe Today

A volcano in Greece that lay quiet for over 100,000 years may not have been dormant after all, according to new research published April 22 in Science Advances. The findings suggest that some volcanoes long considered “extinct” could still be active deep underground, potentially reshaping how scientists assess volcanic risk.

Researchers studying the Methana volcanic system, located about 50 kilometers from Athens, discovered evidence that magma continued to develop beneath the surface even during long periods without eruptions. By analyzing tiny zircon crystals found in volcanic rocks, the team reconstructed a detailed timeline of the volcano’s activity spanning 700,000 years.

The study revealed two major eruptive phases, separated by a long quiet interval between roughly 280,000 and 168,000 years ago. Surprisingly, the highest production of zircon crystals occurred during this so-called dormant period, indicating that magma was still forming below ground despite the absence of eruptions.

Scientists believe water-rich magma may explain this prolonged silence. Under high pressure deep within Earth’s crust, water helps keep magma fluid. But as magma rises and pressure decreases, the water escapes as gas similar to opening a carbonated drink. This process can cause the magma to thicken and stall before reaching the surface, preventing eruptions.

The findings highlight that volcanic systems can remain active internally even when they appear inactive on the surface. This could have significant implications for how volcanoes are classified and monitored.

Experts say the research may help improve forecasts of volcanic hazards by focusing not just on eruption history, but also on underground processes such as magma chemistry. As a result, some volcanoes previously labeled as “extinct” may need closer observation in the future.