A volcanologist has described the ongoing Reykjanes eruption as typical for shallow magma chamber eruptions, where built-up pressure leads to rapid magma ascent followed by a quick decrease in intensity. The volcanologist also noted that there are indications that the current eruption may be short-lived.
Eruption in Grindavík unlikely
In an interview on the radio station Rás 2 this morning, volcanologist Þorvaldur Þórðarson characterised the ongoing eruption on the Reykjanes peninsula as typical for eruptions originating from a shallow magma chamber, where magma has been injected into a chamber over a significant period of time, causing pressure to build.
“Once that pressure becomes so great that it equals or exceeds the threshold of the chamber’s roof, it breaks, and the magma ascends very quickly. This extra pressure from the accumulation of magma drops rapidly, causing the eruption to decrease swiftly. This is actually a classic example of such eruptions.”
Asked about the likelihood of new vents opening on the fissure as activity diminishes, Þorvaldur believes the chances are “lower than higher.”
“The risk continually decreases. In my view, there’s almost no chance of an eruption, for instance, in Grindavík, or in its immediate vicinity. However, there’s always a possibility that some craters might reactivate a bit further north. But it seems more likely to go in the other direction.”
Might be over before the weekend
In Þorvaldur’s opinion, it is not unlikely that the area from Eldvörp to Fagradalsfjall might experience more eruptions in the coming years, either on the Sundhnúka rift, along the line in Fagradalsfjall, or possibly slightly westward. “I believe this is not over, unfortunately. There’s an equal chance that we might see a repeat of these events in the coming years.”
When asked to predict the future course of the eruption, Þorvaldur replied that such a thing was difficult. “But many indications suggest that this will be a short eruption that could end within the next few days. Possibly even before the weekend.”