Reykjanes volcano news & activity updates
Thorbjörn volcano (Reykjanes Peninsula, Iceland): volcanic unrest continues with new inflation and earthquakes
Wednesday Jun 17, 2020 06:56 AM | BY: MARTIN
The seismicity around Grindavík last week (image: IMO)The Icelandic Met Office (IMO) reported that in mid-May deformation data (GPS and InSAR measurements) started to show again signs of inflation, suggesting that a third intrusion since the beginning of this year is occurring west of Thorbjörn. The intrusion began around mid of May but the seismic activity started to increase toward the end of the month (30 May). About 2000 earthquakes have been detected since then and several events are located East of Thorbjörn, few kilometers North of the town of Grindavík. The largest earthquake of this swarm occurred on 13 June with magnitude M 3.5.
Since the beginning of the volcanic unrest, in January this year, the total uplift measured in the area is assessed to be around 12 cm. Between the inflation periods, slight deflation has been observed, probably reflecting the cooling of the intruded magma or the interaction with the geothermal system. Numerical modelling results show that this third intrusion is occurring roughly in the same area as the previous ones, i.e. at about 1 km West of Thorbjörn, at a depth of 3-4 km, with a width of few hundreds of meters and oriented NE-SW for about 6 km.
Weekly gas measurements at two sites near the area of the intrusion changes occasionally over time but the interpretation is still unclear. No chemical changes have been detected at the geothermal power plant in Svartsengi. However, measurements of the geothermal system reveal an increased permeability and increased fluid flow in the surrounding rock, which can be linked to the earthquake activity, inflation and uplift in the area, which triggered the creation of new cracks and opening of older ones.
Source: Icelandic Met Office volcano activity update 17 June 2020
Mt. Thorbjorn volcano (Reykjanes peninsula, Iceland): decreased seismic activity; possible re-inflation
Thursday, May 28, 2020
The Icelandic Met Office (IMO) reported that the seismic activity has decreased on Reykjanes peninsula in recent weeks. During the past week (20-27 May) around 120 earthquakes were located there, fewer than in the previous week when they were just more than 200. The largest earthquake was recorded with magnitude M 2.1. ... [more]
Thursday, May 07, 2020
The Icelandic Met Office (IMO) recorded an earthquake with magnitude M 2.3 at 00:49 local time occurred in Grindavík area. ... [more]
Mt. Thorbjorn volcano (Reykjanes peninsula, Iceland): continued inflation; no significant change in activity since the last update
Wednesday, Mar 25, 2020
The Icelandic Met Office (IMO) recorded an earthquake with magnitude M 2.5 at 16:55 local time occurred N of Grindavík. The earthquake was felt in Grindavík. Considerable seismic activity has been ongoing in the area during the last weeks in connection with deformation in the area. The deformation is measured at a slower rate than in January, but still continuing in magma accumulation at depth. The deformation is occurring in the same location as before. ... [more]
Friday, Mar 20, 2020
The Icelandic Meteorological Office (IMO) report that the inflation and associated uplift that occurred around Mt Thorbjorn volcano in January-February has started again. The deformation is occurring in the same location as before, but at a slower rate. The uplift started in January but paused temporarily at the end of February. The IMO suggest that since the beginning of March, the uplift is about 20 mm. The deformation is believed to be caused by continued magma accumulation at depth. The head of the National Hazard Monitoring Group at the IMO explains that these events doesn’t not guarantee that there will be an eruption any time soon. ... [more]
Friday, Mar 13, 2020
The Icelandic Met Office (IMO) recorded an earthquake with magnitude M 5.2 occurred about 5 km NE of Grindavík. Multiple aftershocks have been detected. The earthquake is the largest earthquake detected on the Reykjanes peninsula since October 2013 when an earthquake of magnitude M 5.2 occurred close to Reykjanestá. The earthquake was felt in large areas of SW-Iceland. ... [more]