Clear deformation marks are visible on the latest InSAR satellite images of the Reykjanes Peninsula, covering the period 20-26. December. The deformation that is taking place now is very similar to the deformation that was observed in late February when magma formation was forming under the Fagradalsfjall area. These results are consistent with GPS measurements showing deformation in the same area.
Volcanic eruptions could start in the short term
The civil defense and the police chief of Suðurnes have decided to activate the SMS messages that will be sent to people entering a predefined area due to the earthquakes that have resumed at Fagradalsfjall in Reykjanes.
In the event of an eruption, the SMS will be transformed into a direct warning to people in the area in question.
Reykjanes Peninsula - interferogram between 20 and 26.12.2021 / surface deformation over the period - Image processing Michelle Parks. via IMO
Reykjanes Peninsula - location and magnitude of the earthquakes of the current swarm, as of 12/27/2021 / 9 a.m. - Doc. IMO
Since the start of the swarm, more than 15,000 earthquakes have been detected.
The biggest earthquake is M4.9 occurred at 9:23 am yesterday 12/22.
Since the start of the swarm, 92 earthquakes have been M3.0 or more, of these 14 have been M4.0 or more
The mean depth of hypocenters is stable, with the majority of hypocenters located between 4 km and 6 km below the surface.
No volcanic tremor pulse has been detected today so far.
As stated earlier, it should be considered most likely that if an eruption occurs it will likely be in or very near the areas where the Geldingadalir eruption has occurred, but it cannot be excluded that the magma could cross the surface somewhere in the area between Nátthagi and Keilir.
Source: IMO, Civil Defense and the Suðurnes Police Chief
Piton de La Fournaise -image 12.26.2021 / 12:17 p.m. - IRT / OVPF-IPGP webcam - one click to enlarge
At Piton de La Fournaise, over the last 24 hours, the amplitude of the eruptive tremor (indicator of a surface lava emission) shows fluctuations.
These fluctuations can be linked either to:
- the cone under construction which undergoes construction and dismantling phases, thus influencing the speed of the lava flows at the level of the vent;
- or to punctual releases of pockets of gas trapped in the supply ducts which can be released suddenly leading to an increase in the tremor.
The amplitude of the tremor is (on average over the last half-day) about 30% of its initial amplitude.
Piton de La Fournaise - Evolution of the RSAM (indicator of a surface lava emission) between 12/21/2021 2:00 p.m. local time (6:00 p.m. UT) and 12/27/2021 10:00 a.m. (local time, 10:00 a.m. UT time) on the FOR seismological station located at the level of the Château Fort crater (© OVPF / IPGP).
Piton de La Fournaise - lava at the foot of the cone on 12/26/2021 / 06h50TU - Piton de bert-1 / OVPF webcam - one click to enlarge
Piton de La Fournaise - modification at the foot of the cone on 12/27/2021 / 02:31 GMT - Piton de bert-1 / OVPF webcam - one click to enlarge
The lava tunnel activity set up at the foot of the cone since 12/23/2021, thanks to the closure of the cone, continues, with occasional resurgences of flows. Following the resurgences observed yesterday, a second mouth was visible at the foot of the cone this morning. The main flow does not emerge in a single channel until about a hundred meters downstream. Lava fountain activity within the cone is low, and lava fountains exceed the height of the cone (<15 m) only intermittently. observable at the foot of the eruptive cone.
Piton de La Fournaise - InSAR interferogram between 14 and 26.12.2021 - Doc. Mounts project - one click to enlarge
Over the last 24 hours:
- A single volcano-tectonic earthquake under the summit was recorded.
- Surface deformations no longer show significant deformation.
- The lava flow estimates, established by satellite method with the HOTVOLC platform (OPGC - Clermont Auvergne University), are between 3 and 12 m³ / sec. These variations are explained by the method, which is based on the infrared radiation of the flow, the perception of which by satellites can be largely influenced by the weather conditions above the flows.
- The front of the flow, in graton, currently on a relatively flat area, moves only very slowly. The flow front advanced less than 100 meters between December 24 and 26.
Sources : OVPF, Mirova and Mounts project
Find all the information relating to Piton de la Fournaise's activity on the various OVPF-IPGP media: - the website: ipgp.fr/fr/ovpf/actualites-ovpf - the Twitter account: twitter. com / obsfournaise - the Facebook account: facebook.com/ObsVolcanoPitonFournaise.
Rincon de La Vieja - eruption, overflow of acid lake and lahar on 12.25.2021 - photo Volcanes sin Fronteras
On December 25 at around 10:15 a.m., an eruption occurred in the active crater of the Rincón de la Vieja volcano, in Costa Rica.
This event generated the outflow of hot and acidic water from the lake and, along with the heavy rains, lahars formed. These affected the Pénjamo, Azul and Niño de Upala rivers.
Neighbors report dead fish and a milky color from the tributaries.
Sources: Ovsicori & Volcanes sin Fronteras