The eruption that began on 04/09/2021 at 7 p.m. at Piton de La Fournaise (appearance of the tremor) continues. The intensity of the volcanic tremor (indicator of a surface lava emission) over the past 24 hours has remained relatively stable and comparable to that observed in previous days
Observations of the eruptive site made during an overflight aboard a microlight on April 20 still show:
- a main eruptive cone and a secondary eruptive cone about a hundred meters downstream (resulting from the merger of the two secondary mouths which were still visible at the end of last week), each presenting an activity of lava fountains and degassing,.
- a flow activity focusing on the plateau downstream of the eruptive site, with a regime of lava tunnels showing this morning a main resurgence about a hundred meters from the secondary cone.
- the absence of active flow at the level of the Grandes Pentes with a front which therefore remains frozen just upstream of Piton le Bonnet.
Piton de La Fournaise - the lava flow front located in the Grandes Pentes - Doc. OVPF 20.04.2021 / 08h00 local
Over the last 24 hours, 12 superficial volcano-tectonic earthquakes (between sea level and the surface) have been recorded under the summit craters.
The CO2 fluxes in the soil are still increasing both in the far field (Plaine des Cafres and Plaine des Palmistes) and in the near field (Gîte du volcan).
The deflation of the building has stopped and a slight inflation of the top seems to be emerging. This parameter will be monitored over the next few days because it may correspond to the arrival of deep magma, highlighted by the flow of CO2 in the soil for several days, in the superficial magmatic reservoir that feeds the current eruption.
Debit estimates, made from the SO2 fluxes measured by the DOAS “NOVAC” network, make it possible to propose a first estimate of the total volumes (lava flows + pyroclastic cones) emitted during the eruption as well as their evolution in the time. Thus, since the start of the eruption, the total volume emitted would be around 7 million m3.
Fagradalsfjall eruption continues without much change
A magnitude 4.1 earthquake was measured at 11:05 p.m. on 20.04.2021 about three kilometers northeast of Mount Þorbjörn (6 km southwest of Fagradalsfjall). On the surface, old craters are called Sundhnúkagígaröðin.
An announcement from the Icelandic meteorological office says the earthquake was felt in many parts of the southwest, south and west, all east of Hella and north of Grundarfjörður. Several aftershocks followed.
Comparison of the extent of the lava fields of the last eruptions in Iceland - Doc. 20.04.2021 / Jarðvísindastofnun Háskólans
Scientists have compared recent lava eruptions in Iceland over the past quarter century. On the attached map, the lava that formed during the eruptions at Hekla in 2000, Fimmvörðuháls and Eyjafjallajökull 2010 and Holuhraun has been placed over a map of the Reykjanes Peninsula. Recently formed lava is shown in red. It makes it possible to put into perspective the size of the lava fields produced on 04.20.2021.
Source: IMO and Univ. from Iceland
Explosive activity continues at Ili Lewotolok in recent days.
The PVMBG relates that of Tuesday, April 20, 2021 at 08:31 WITA with an ash column ± 750 m above the peak (± 2173 m above sea level). This eruption was recorded on a seismograph with a maximum amplitude of 6.2 mm and a duration of 23 seconds.
Ili Lewotolok presented this Wednesday, April 21, 2021, at 05:37 WITA a new episode, accompanied by an ash plume observed at ± 1,000 m above the summit (± 2,423 m above sea level). This eruption was recorded on a seismograph with a maximum amplitude of 7 mm and a duration of 94 seconds.
The activity level remains at 3 / siaga, as the activity continuing.
Source : PVMBG &Magma Indonesia