Exploring Mayotte’s magmatic plumbing system using the variety and geometry of its seismicity

The seismic sequence off the coast of Mayotte island, in the Comoros archipelago, preceded and accompanied the large submarine volcanic eruption and birth of the volcano Fani Maoré. While this sequence has slowed down and the eruption has stopped, it is still active and captures the deep complex system of this new volcano and its evolution. The seismicity is separated in two clusters. The distal cluster is located about 25 km South-East of Mayotte and has been associated with the magma propagation towards the surface. The proximal cluster, about 10 km East of Mayotte, suggests the presence of several magmatic reservoirs and conduits. We built a new catalog using deep learning methods from land and ocean bottom seismometers data from 2019 to 2023. We locate this seismicity using NonLinLoc and a 1D velocity model developed in 2020 specifically for this seismic sequence. We analyze the volcano-tectonic and long period earthquakes spatio-temporal patterns as well as their mechanism to understand the volcanic system. We compare this analysis with recent modeling studies that suggest interactions between reservoirs.