Volcanological Observatory of Piton de la Fournaise (OVPF-IPGP)

Since the arrival of the first permanent inhabitants on La Réunion Island at the end of the 17th century, observations of a sustained activity of Piton de la Fournaise volcano have been reported. Nonetheless, already in the 13th century, Arab sailors reported observation of an island in the east of Madagascar where “the fire spouts out permanently”.

In 1936, Alfred Lacroix expressed the wish for the installation of a volcanological observatory for the study of Piton de la Fournaise. He said: “No instrumental observation was made and it would be to wish that a seismograph was installed near the volcano to record the microseismic movements which certainly accompany the rise of the lava, at the time of the paroxysms”.

It is only about 40 years later, following the eruption outside the caldera in 1977, which partially destroyed the village of Piton Sainte Rose, that the authorities, the department de La Réunion and the CNRS decided to establish a volcanological observatory and entrusted its management to the Institut de Physique du Globe de Paris.

The observatory was operational at the end of 1979.

It is located in Plaine des Cafres, at a straight-line distance of 15 km from the summit of the volcano, and the data transmission in real time allows monitoring of the activity in real time.

Piton de la Fournaise is one of the most active volcanoes in the world with an average of an eruptive phase every 8 months. The activity of Piton de la Fournaise is followed 24/24 by the volcanological observatory through several monitoring and research networks (see next section).

The OVPF has three main missions :

. the monitoring of Piton de la Fournaise with in particular the follow-up of eruptions and lava flows,

. research on volcanoes behavior and evolution,

. and the diffusion of knowledge.

In addition to these three missions, since 2020, the observatory is in charge of the operational monitoring of the seismic activity of Mayotte through REVOSIMA (Réseau de surveillance volcanologique et sismologique de Mayotte)

The monitoring of Piton de la Fournaise activity requires the permanent surveillance of geophysical and geochemical phenomena associated to the circulation and storage of fluid at depth, and their integration in the geological knowledge of past eruptive activity and the possible future eruptive scenarios.

For this, the OVPF-IPGP maintains five different networks with about 100 instruments installed on the island mainly on Piton de la Fournaise but also on the Piton des Neiges:

– the seismological network,
– the ground deformation monitoring network with tiltmeters, extensometers, and GPS receivers,
– the geochemical network carrying out measurements of SO2, H2S and CO2 in the summit fumaroles and of CO2 in the soil in far field,
– the network of cameras,
– the meteorological network (rain gauges).

The networks operate continuously, 24 hours a day, 365 days a year. The instruments are maintained, repaired and constantly perfected. The proper functioning of the networks is checked daily by the observatory staff.
All these data allow the observatory to monitor the volcano activity real time and to warn Etat Major de Zone et de Protection Civile de la Zone Océan Indien of any change in activity and the imminence of an eruption. These data are disseminated by the observatory via daily and monthly bulletins, and via exceptional press releases during any change in activity or during an earthquake felt on the island.

Data analysis and experimental research carried out at the observatory and at the Institut de Physique du Globe de Paris have improved our understanding of the eruptive mechanisms of Piton de la Fournaise in particular and of basaltic volcanoes in general. In return, this knowledge has been used to improve methods of observing and anticipating eruptions.

List of eruptions and collapses at Piton de La Fournaise between  1998 and 2022

(last update: 23/12/2022)

E-L : Lateral Eruption  ;  E-C : Summit eruption in the summit crater ;  Co : Collapse