Monitoring cooling and flowing magma

Magma currently flowing beneath Svartsengi originates from a depth of about 15 kilometers, according to Halldór Geirsson, a professor of geophysics at the University of Iceland. He explained that the pressure at this depth is steadily decreasing as magma has been extracted over the past two and a half years.

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The magma that is flowing in there under Svartsengi is coming from somewhere deeper, perhaps from about 15 kilometers deep or something like that, and the pressure down there is steadily decreasing as more magma has been taken out these past two and a half years.

This reduced pressure leads to a slower magma inflow. Geirsson noted that in some areas, like Sundhnúka, the magma chamber has been breached. This has created a dynamic situation where magma cools and solidifies in the vents, blocking them, while the inflow slows down. The critical question remains: which process will become dominant?

Geirsson stated that the region is now approaching certain limits of expansion, considering how the situation has been managed. However, because it takes a long time to reach these limits, the Earth's crust has strengthened in the interim. This leads to significant uncertainty in predicting the timing and likelihood of future eruptions.

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This makes the inflow slower, and the magma chamber has been breached in some places, like there at Sundhnúka. There will be a certain competition. The magma cools and solidifies in these vents and blocks it, and then the inflow slows down. The question is when and which factor will be dominant.

In a discussion on Dagmál, Geirsson also addressed seismic activity in the Reykjanes Peninsula and other areas. He elaborated on the interplay between volcanic systems in the Reykjanes Peninsula, the current situation in Svartsengi, and potential future geological events, acknowledging the inherent difficulty in making precise predictions.

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Now we have actually come to certain limits of expansion compared to how it was managed, but because it takes such a long time to get there, the Earth's crust has become stronger in the meantime, and this causes so much uncertainty in predicting the timing and also just whether another eruption will occur or not.