Referência Bibliográfica
Publication_BiblioReference
MATOS, S., GHERI, D., BELLI, G., JESUS, M. C., WALLENSTEIN, N., MARCHETTI, E. (2023) - 2022 São Jorge Island (Azores) seismo-volcanic crisis: infrasound radiation by low magnitude earthquakes. Infrasound Technology Workshop 2022 (ITW2022), Ponta Delgada, Azores, Portugal, January 30th to February 3rd.
Resumo
PublicationAbstract
São Jorge Island is one of the five volcanic islands of the central group of the Azores Archipelago, in the middle of the North Atlantic Ocean. On 19 March 2022 a seismovolcanic crisis began in the western part of the island, under the active Manadas Volcanic Fissure System, related to a possible unrest associated to a magmatic intrusion. A collaborative partnership between the University of the Azores and the University of Florence (UniFI), allowed to deploy a portable infrasound array (SJ1) on the island at ~7 km from the main epicentral area (MEA), two weeks after the beginning of the crisis. Two events were detected at IMS IS42 infrasound station (located at Graciosa Island at a distance of ~42 km from MEA), the first one associated to the most energetic earthquake of this crisis (a 3.8 Richter scale magnitude), the second to a 2.1 Richter scale magnitude event, the latter being also detected by SJ1. We present the preliminary analysis of the SJ1 and IS42 data, which were correlated with the seismic events recorded by the local CIVISA/IVAR seismic network, aimed to investigate the infrasound radiation processes by low magnitude earthquakes.