Askja volcano (Central Iceland): uplift slowed down

Thu, 5 Oct 2023, 05:17 | BY: MARTIN

The plot shows the cGNSS data from the station KASC located within Askja caldera. The time series shows the trend of the deformation since November 2022 in the North, East and Up components, and the green dot shows the latest measurement acquired (image: IMO)

The latest deformation data (cGNSS) revealed a subsidence of the edifice since early August.
Several monitoring stations found multiple sites flattened within and/or around the caldera. At this stage, it is uncertain what process is causing this pressure reduction; possibly, the source of the inflation has been shut off, or it could be related to an outflow of magmatic fluids.
Regular geodetic measurements around Askja have shown historic periods of subsidence and a period of uplift, which did not result in an eruption. The IMO continues to monitor the area, which is still at the uncertainty level. The latest data needs to be modelled and interpreted to understand what process is responsible for this recent change. A new seismic station was also installed last week (west of Askja) to improve earthquake relocations.
The available data at the end of August 2023, which includes the results of the geochemical field campaign data collected in the summer, confirmed that at that time (August 2023), there was no increase in the geothermal activity within Askja nor any evidence of magma becoming shallower.
It is quite a challenge to maintain monitoring equipment during the wintertime, but Askja will be visited to install additional instrumentation, i.e. cameras and thermocouples.
Source: Icelandic Meteorological Office volcano activity update 5 October 2023