Something preoccupating is happening in the south-west Reykjanes Peninsula in Iceland.
Unusual and sudden land uplift accompanied by a seismic swarm are being recorded by GPS and seismometers around Mt. Thorbjorn. This indicates that magma accumulates and underlines the possibility for an upcoming eruption at Þorbjörn volcano. Meanwhile, the aviation color code has been raised to Yellow.
Since january 21, 2020, an unusually rapid inflation – 3-4 mm per day and up to 2 cm in 5 days – has been detected – GPS and InSar satellite imagery – just west of Mt. Thorbjorn on the Reykjanes peninsula in Iceland.
The inflation most likely indicates a small magma accumulation – 1 million cubic meters (0,001 km3) – is taking place at a depth of just a few km beneath the volcano.
In the last three decades of crustal deformation measurements of the Reykjanes peninsula no comparable signal has been measured.
In parallel, an earthquake swarm has also started on January 21, 2020, just east of the inflation center, with the largest quakes measuring M3.7 and M3.6 and felt across the Reykjanes peninsula and all the way to Borgarnes region.
Although such swarms are common in the region, the cause of concern is it’s occurring at the same time thant the inflation event.
Inflation located in active volcanic zone
The inflation is occurring on plate boundaries and within the volcanic system of Svartsengi which is either considered a separate system or part of the Reykjanes volcanic system for which the last known eruption occurred between 1210-1240 AD.
In this time interval, the Svartsengi system blew three times opening large fissures in the gound. No explosive eruptions are known from this system.
Historically, the duration of these eruptions spans from a few days up to several weeks.
Seismic activity is very common in this area and is linked to the plate boundaries, geothermal activity and possible magma intrusions.
The activity has only been ongoing for a few days and it is uncertain if it will escalate to more serious activity.
Based on current information, the following scenarios are considered possible:
1. If the inflation is due to magma accumulation:
- Magma accumulation will cease soon without further activity.
- Magma accumulation continues for some time without further activity.
- Magma accumulation will lead to a magma intrusion.
- Magma accumulation will lead to magma intrusion and eruption (effusive fissure eruption).
- Magma accumulation triggers seismic activity with larger earthquakes (up to M6.0).
2. If the inflation is not caused by magma accumulation:
- The inflation might be linked to tectonic activity and lead to larger earthquakes (up to M6.0).
The National Commissioner of the Icelandic Police in cooperation with the Police Commisioner on Reykjanes has declared a state of uncertainty and increased the aviation color alert to yellow. More apocalyptic volcanic scenarios Strange Sounds or Steve Quayle. [Vedur, Facebook]