Referência Bibliográfica
Publication_BiblioReference
JESUS, M.C., BELLI, G., GHERI, D., MATOS, S., WALLENSTEIN, N., MONTALVO, A., MARCHETTI, E. (2023) - 2022 São Jorge Island (Azores) seismovolcanic crisis: deployment of a mobile infrasound array (SJ1) for local monitoring purposes. Infrasound Technology Workshop 2022 (ITW2022), Ponta Delgada, Azores, Portugal, January 30th to February 3rd.
Resumo
PublicationAbstract
On 19 March 2022, seismic activity suddenly increased on São Jorge Island, being associated with a possible unrest of Manadas Fissure Volcanic System, where historical eruptions occurred in 1580 and 1808. To locally monitor the evolution of seismicity and eventual eruptive activity, we immediately started a site survey to deploy a mobile infrasound array around the epicentral area. Firstly, several sites were pre-selected using a terrain imagery software. On 1 April 2022, in a collaborative work between IVAR-CIVISA and UniFI, those spots were evaluated in situ. On the most ideal site, we installed a 4-element infrasound array (SJ1), configurated in a diamond geometry with an aperture of ~ 115 m. After 1 month, having more resources, the array design was rearranged into a triangular geometry with a central element, extending the aperture to ~ 130 m. SJ1 has been remotely acceded by GSM transmission and data are broadcasted in real time to IVAR and UniFI servers. 24-h periods of data were processed to analyse PSDs for both array configurations, which are herein compared and discussed about their signal-to-noise ratio and detection capability.