Super Volcanic Eruption Happens When Massive Magma Building Up For Millions of Years Rapidly Moves Downward and Suddenly Rises [Study]

University of Bristol researchers and the Scottish Environmental Research Centre have published new findings about super volcanic eruptions. The new study claims that a super volcanic eruption happens when massive magma accumulations that have been building up deeper in the Earth's crust for millions of years rapidly move downward and rupture pre-existing rock.

They were able to show that pre-existing plutons, which are intrusive rocks made of magma or solidified lava, formed over a few tens of millions of years before four extremely powerful known eruptions occurred by using the crustal flow model.

Movement of Massive Magma Is Behind Super Volcanic Eruptions

Based on the findings published in Nature, the magma responsible for the super volcanic eruptions first disturbs the crust over a long period of time before bursting within a few decades.

The results imply that these extreme differences in time intervals for magma generation and eruption are accounted for by the flow of hot, solid crust in response to rising magma, which also explains the rarity of these eruptions and their enormous volumes.

The short timescales required for the assembly of shallow magma chambers prior to large-magnitude eruptions of molten rock contrast with the longevity of plutonic and related volcanic systems.

Crystals produced by previous magma pulses entrained within erupting magmas typically only remain in the host magmas for a few decades or less and are typically stored at temperatures close to or below the solidus for lengthy periods before the eruption.

St. Helens Volcanic Eruption
St. Helens Volcanic Eruption WikiImages/Pixabay

Theory on Old Crystal During Super Volcanic Eruption

The study questions the theory that old crystals were stored for a long time at high temperatures enough to have some molten rocks. It shows the crystals formed from plutons that had already been deposited and solidified into granite.

Scientists have long known that crystals from older rocks are ejected during volcanic super-eruptions. However, it was widely believed that it originated in warm regions above the rock melting points.

There is no logical explanation for the previous studies' findings that the magma chambers for super-eruptions form quickly. Modeling suggested that extremely prolonged periods of granite pluton emplacement in the upper crust would be required to precede super volcanic eruptions. Still, there was little evidence to support this hypothesis.

According to Professor Steve Sparks of Bristol's School of Earth Sciences, we can learn more about how these eruptions happen by examining the age and makeup of the tiny crystals that erupted alongside the molten rock.

The study advances our knowledge of the geological conditions necessary for super volcanic eruptions, making it easier to locate volcanoes that could experience such explosions in the future. According to Bristol scientists, only one of these types of eruptions is thought to occur on Earth every 20,000 years. However, such eruptions can cause severe climate change on a global scale, which would have disastrous effects, and are extremely destructive locally.

Volcanic eruptions have the power to destroy economies and alter the climate. They could release dangerous gases and other substances that would wreak havoc for years. Being aware of volcanic activity may help one prepare for such a disaster.

Check out more news and information on Environment in Science Times.

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