Glaciers and volcanic eruptions

What have to do with each other? It turns out that the melting of the glaciers would trigger more explosive and frequent volcanic eruptions in the future. An investigation into six volcanoes in the Chilean Andes, carried out by the University of Wisconsin-Madison (USA) confirms it. They studied the relationship between glaciers and volcanic eruptions.

There are hundreds of inactive subglacial volcanoes worldwide, particularly in Antarctica. They could become more active as climate change accelerates the recoil of glaciers.

Volcanoes waking up

The relationship between the recoil of the glaciers and the increase in volcanic activity has been known in Iceland since the 1970s. This is one of the first studies that explores the phenomenon in continental volcanic systems. The findings could help scientists understand and predict volcanic activity in regions covered by glaciers.

The researchers used the Datation by Argon and the analysis of crystals in six volcanoes in southern Chile. They investigated how the advance and setback of the Patagonian ice layer influenced past volcanic behavior. They discovered something happened during the peak of the last ice age (about 26,000 to 18,000 years). A thick layer of ice suppressed the volume of eruptions. It allowed a large reserve of rich Magma in silica to accumulate 10-15 km below the surface.

When the ice cap was melted, the sudden weight loss caused the relaxation of the bark and the expansion of the magma gases. This pressure accumulation triggered explosive volcanic eruptions from the deep reservoir, which gave rise to the volcano.

Response time

This would happen in Iceland as in Antarctica. The volcanic response to the melting of glaciers is almost instantaneous in geological terms. But the process of changes in the magma system is gradual and occurs for centuries. There is still time for early alert.

Glaciers and volcanic eruptions are part of a cyclical process. «The cumulative effect of multiple eruptions can contribute to long -term global warming. It is due to the accumulation of greenhouse gases, ”they affect. «This creates a positive feedback cycle. The melting of glaciers triggers rashes, and these, in turn, could contribute to greater heating and melting ».