Evolution of the Volcano-Tectonic seismicity associated with Mayotte's active magmatic system

Aude Lavayssière (1) , Lise Retailleau (1, 2)

1 IPGP (UMR_7154) - Institut de Physique du Globe de Paris
2 OVPF - Observatoire Volcanologique du Piton de la Fournaise

In May 2018, a seismic crisis started East of Mayotte which was widely felt on the island and has been linked to the discovery of a new active submarine edifice. In order to reconstruct the evolution of the crisis with more details on the active structures we re-analyze the seismicity from March 2019 to February 2021 and focus on its evolution throughout the eruption. We use a catalog built by using the neural network-based method PhaseNet, which considerably increased the number of detected earthquakes and enabled a deeper analysis of the seismicity variations. Moreover, the development of a new velocity model for the region allowed a precise location of these earthquakes using only land-stations data. We show that the geometry of the seismicity has evolved in the two main clusters of activity with a general decrease in activity in the proximal cluster and no decrease in activity in the distal cluster. Spatial evolutions of different sub-clusters can be identified over time. This analysis is essential to understand the dynamics of the volcanic and magmatic processes beneath Mayotte island and will provide crucial details on the dynamics of submarine eruptions.

Mots clés: RESIF; Seismology; Volcano; Mayotte; Epos-France

Mots clés: RESIF; Sismologie; Volcan; Mayotte; Epos-France

Domaines: Géophysique [physics.geo-ph]

Aude Lavayssière, Lise Retailleau. Evolution of the Volcano-Tectonic seismicity associated with Mayotte's active magmatic system. 5èmes Rencontres Scientifiques et Techniques Résif, Nov 2021, Obernai (67210), France. ⟨hal-03442572⟩