Two earthquakes in Bárðarbunga volcano

Because of other activity in Iceland. This article is going to be short.

Two earthquakes took place in Bárðarbunga volcano at 19:59 UTC and 20:02 on 4. July 2023. The magnitudes was Mw3,3 and Mw3,9.

Two green stars on top of each other in Bárðarbunga volcano in Vatnajökull glacier.
Earthquake activity in Bárðarbunga volcano. Copyright of this image belongs to Icelandic Met Office.

This is normal activity and happens because of inflation in Bárðarbunga volcano.

Earthquake swarm in Fagradalsfjall mountain

Today (4. July 2023) there has been a earthquake swarm in Fagradalsfjall mountain. Largest earthquake had a magnitude of Mw1,6 and at the writing of this article there have not been any earthquakes with magnitude above Mw2,0. This might change without warning.

Red dots in Fagradalsfjall and yellow and blue dots in other places on Reykjanes peninsula.
Earthquake activity on Reykanes peninsula. Copyright of this image belongs to Icelandic Met Office.

Smaller earthquakes swarms sometimes seems to happen before an eruption in Fagradalsfjall mountain. The current earthquake swarm has all signs of dyke intrusion. If that is going to result in eruption now is impossible to know.

Reykjanes peninsula might be one large volcano

It was in the news today (3. July 2023), since inflation has been detected from GPS data on Reykjanes peninsula since start of April. What was told in a interview on Bylgjan (radio channel) and later published on Vísir.is news website (link below, but the whole thing is in Icelandic) is that all of Reykjanes peninsula is inflating. What is also starting to show in the GPS data is that there might not be separate volcanoes on Reykjanes peninsula, this might also have happened in the year 2020 – 2021, before the first eruption in Fagradalsfjall mountain. All of Reykjanes peninsula might be one large volcano, extending from Hengill to Eldey or Eldeyjarboða, the south end might have uncertain location. This changes everything as that means that it can erupt at any location on the Reykjanes peninsula without warning and the whole area is now in an eruption cycle.

The current period of inflation started in April and is now at 2,5cm (25mm) and is centered at the last eruption location in Fagradalsfjall mountain. That means the most likely location of next eruption is going to be Fagradalsfjall mountain. This inflation is also going to trigger large earthquakes on Reykjanes peninsula in next few weeks to months until an eruption starts. Along with the normal amount of small earthquakes that have been happening since April on the whole of Reykjanes peninsula.

I don’t know when or how long it is going to take to change the official definition of the Reykjanes peninsula. Because this is going to require more research and data collection for the scientists in Iceland. This also means a lot of new science papers have to be published and peer-reviewed.

Icelandic news

Fólk á suð­vestur­horninu má búa sig undir reglu­lega jarð­skjálfta (Vísir.is)

Earthquake in Katla volcano

During the evening of 2. July 2023 at 22:57 UTC an earthquake with the magnitude of Mw3,1 took place in Katla volcano caldera. This was one of the few earthquakes that took place that evening and there has not been any more earthquake activity since then.

Green star in Katla volcano caldera. There are also few blue dots showing older earthquakes, along with few yellow and orange dots.
Earthquake activity in Katla volcano. Copyright of this image belongs to Icelandic Met Office.

Since the last earthquake swarm in Katla volcano. Things have been rather quiet in Katla volcano.