Eruption of La Fournaise and Nevados de Chillan.

At Piton de La Fournaise, the eruption did not last very long.

I enclose the activity bulletins of April 3rd in the evening and this morning.

Activity Bulletin from Tuesday, April 3, 2018 at 5:30 pm (local time)
The eruption started on April 3, 2018 at 10:40 am continues. The volcanic tremor (indicator of eruptive intensity at the surface) continues to intensify, especially on the seismological stations located north of the volcano.

Following a reconnaissance made by a team of the OVPF at the ramparts of the Enclos, the eruptive activity could be confirmed. It is located on the north flank of the volcano against the top of the broken slopes.

A helicopter overflight of the eruptive site by a second team of the OVPF in the middle of the afternoon allowed to locate more precisely the eruption.

Piton de la Fournaise - Evolution of the RSAM (indicator of the volcanic tremor and the intensity of the eruption) between 3:00 am (23:00 UTC 02) and 15:30 (11:30 UTC) on April 3, 2018 on the seismic station of NSR, located on the northern flank of the volcano (© OVPF / IPGP)

A long crack about 1km long opened in 7 distinct segments, two with emissions of lava fountains. The last active segment is just at the foot of the rampart against the bottom of the Nez Coupé de Sainte Rose

At 16:00 local time, many landslides were recorded by the OVPF network in the rampart at the Nez Coupé de Sainte Rose area, and many fumaroles were observed on site at this level. This situation presents a real and imminent danger of collapse. As a result, the Nez Coupé de Sainte-Rose trail is currently closed to pedestrian traffic from Piton Partage

Piton de La Fournaise - Photograph of the eruptive site in the late morning (11h50) (© OVPF / IPGP)

Piton de La Fournaise - 03.04.2018 - the crack and the two active segments - IPR photos

Piton de La Fournaise - 03.04.2018 - one of the active vents - photos IPR

Piton de La Fournaise - 03.04.2018 - lava flows and lava fountains near the ramparts - photo IPR

Piton de La Fournaise - a slight incandescence is reflected on the clouds on this view of the webcam Piton Basalte 03.04.2018 / 14:49 UT - OVPF

Activity Bulletin from Wednesday, April 4, 2018 to 08:30 (local time)

Following a very sharp fall in volcanic tremor (indicator of surface eruptive intensity) at 1 o'clock (local time, 21h UTC), surface eruptive activity started on April 3, 2018 at 10:40 am local time stopped. day, April 4, 2018 at 4:00 am (local time, 00h GMT), after a gas piston phase.

Piton de La Fournaise - Evolution of the RSAM (indicator of the volcanic tremor and the intensity of the eruption) between 3 April 3:00 (23h UTC) and 4 April 6:00 (2h UTC) 2018 on the seismic station of NSR, located on the northern flank of the volcano. (© OVPF / IPGP)

No assumptions are made about the evolution of the future situation (permanent shutdown, resumption of activity on the same site, resumption of activity further downstream whether it is inside or outside Enclos Fouqué), taking into account the following observations:

• Many earthquakes under the Plaine des Osmondes sector.
• Many landslides in the rampart of the Nose Coupé de Sainte Rose.
• The location near the rampart of the eruptive fissure.

Sources: OVPF & Fournaise-info

Piton de La Fournaise - 2018.04.03 - Location of eruptive fissures and lava flows emitted during the eruptive phase of April 3, 2018. (© OVPF-IPGP)

In Chile, Nevados de Chillan's activity took place from March 7 to 31 with degassing, explosions and sporadic incandescence in the crater, in which a dome is extruded.

The explosions occurred on March 10, 11, 12, 17, 26 and 31, the latter being the strongest. A thermal anomaly has been observed by the ESA satellite since the beginning of the dome extrusion.

From the before-after photos, there are no significant changes in the dome's physiognomy.

Source: Sernageomin & Volcanes of Chile