Earthquakes Calming, Reminding Scientists Of Last March’s Pre-Eruption Events

The earthquake swarm which began on December 21st has been considerably calmer over the past 24 hours or so, but we are not out of the woods yet.

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A mere 118 earthquakes were recorded over the entire country from midnight last night, 105 of them in Reykjanes, at the time of this writing. Almost all of these have been very mild–according to the latest data from the Icelandic Met Office, only two quakes measuring greater than a magnitude of 3 have been recorded since midnight last night, both just a few kilometres north of Krýsuvík, the largest of them being a 3.9 at 14:29 yesterday. There was also a 3.7 at 10:22 this morning.

That said, scientists are noticing a pattern that is very reminiscent of events preceding the Geldingadalur eruption of March 2021.

Þorvaldur Þórðarson, a professor of volcanology and petrology at the University of Iceland, told RÚV: “If you look at the pattern of seismic activity, it’s very similar to that which happened before the March 19th eruption earlier this year. Both in the number of quakes and the power being released due to the quakes. But it’s a lot less; it’s maybe a tenth of what we saw earlier this year. So this is all just a bit calmer.”

Salóme Jórunn Bernharðsdóttir, a natural disasters specialist at the Icelandic Met Office, gave MBL a similar assessment, saying, “Last time, the more powerful quakes decreased, and then eruption came rather quickly to the surface. We can expect the same thing happens now, or see all new behaviour.”

Salomé emphasised that it is impossible to say anything definitive on how likely an eruption will be.

“It is so difficult to say,” she said. “This is a profession that requires incredible caution in predictions. There is so much that plays into this that can have an effect and is unknown. It’s all under the surface, we don’t see it.”