Australian scientists from Curtin University have studied an ancient supervolcano in Indonesia. They found that such volcanoes remain active and dangerous for thousands of years after the super-eruption. The research results are published in the journal Communications Earth & Environment.
Geologists studying the dormant supervolcano Toba on the island of Sumatra in Indonesia have found signs that magma continues to accumulate in its depths. This is evidenced by the slow rise of the solidified lava dome in the volcano’s caldera.
Supervolcanoes are those whose eruption can provoke climate change on the planet. Now there are about 20 supervolcanoes known to science on Earth. Therefore, scientists are trying to understand as closely as possible the mechanisms that lead to the formation of huge volumes of molten magma under supervolcanoes. On average, eruptions occur once every 100,000 years.
Scientists investigated the state of magma that remained after the Toba super-eruption 75,000 years ago. They paid particular attention to feldspar and zircon. The isotopic composition of argon and helium in these minerals helped scientists determine the age of layers of volcanic rocks. It turned out that large eruptions occurred at intervals of about 17,000 years. However, between these events, the volcano was still active. The new study casts doubt on the generally accepted theory that supervolcanoes are harmless to humanity between major eruptions.
“Exploring when and how igneous magma accumulates, and what state the magma is in before and after such eruptions, is critical to understanding supervolcanoes. – scientists note. – We must take into account that eruptions can occur even if there is no liquid magma under the volcano. It’s time to reevaluate the very concept of “eruption”. ”