How do magma chambers form and what happens before an eruption?

Reyðarártindur is a solidified magma chamber that is now exposed at the Earth’s surface in Southeast Iceland. The composition of the solidified magma inside it is the same as in active volcanoes with explosive eruptions. By studying the shape and internal structure of Reyðarártindur, we understand better how magma pools inside a volcano before an eruption and what triggers an explosive eruption from a magma chamber.

How is magma transported on the way to an explosive eruption?

In the Earth’s crust, magma is flowing through fractures that we call dykes. When a dyke reaches the surface, an eruption starts. In this project, we study examples of solidified dykes in the extinct Chachahuén volcano in Argentina. The shapes of the dykes and the solidified magma preserve signs of how the dykes formed and how the magma was flowing. What we learn helps us better understand what is happening inside active volcanoes and improve eruption forecasting.

How does magma behave when it pools inside a shallow magma chamber?

The type of magma that produces explosive eruptions is an interesting material. It can flow, but when put under a lot of stress, it can break, too. In this project, we study magma that was breaking inside the mountain Sandfell in eastern Iceland. Sandfell was once a small magma chamber 500 m beneath the surface of a volcano. The fractures in Sandfell let us understand earthquakes in active volcanoes better, but also help us to locate geothermal and ore resources.

How do ore and geothermal resources form near magma chambers?

Big magma chambers full of molten magma are likely very rare. Instead magma chambers are the sum of many small magma injections over long time. This project studies how heat, fluids, and elements, such as copper and gold, were transported in the solidified Slaufrudalur magma chamber in Southeast Iceland. Slaufrudalur consists of several layers of magma that flowed into a chamber that was finally about 10 km3 big (100 times the volume of the Eyjafjallajökull 2010 eruption).

Can magma-filled fractures become a cheap geothermal heat source?

The heat from magma inside the Earth’s crust is a powerful and sustainable source of energy that is extracted by drilling into active and old volcanoes. Usually, energy extraction targets large magma chambers, but drilling to reach these is expensive. We study whether small magmatic features that are abundant even at shallow depth in active volcanoes could be a more accessible, and thus cheaper, heat source.

How does magma movement in a volcano translate to the Earth’s surface

Magma in a volcano has to create space for itself by pushing the surrounding rocks aside and breaking them. At the Earth’s surface this is detectable as earthquakes and movement, such as land rising, signals that are interpreted in terms of magma moving. However, the interpretation is difficult since it is not possible to directly look inside active volcanoes. We study structures created by moving magma to improve the interpretation of signals from active volcanoes.