Analysis of the seismicity recorded by the LIPARI seismic array in southern Italy
Abstract
We use seismicity to investigate the magmatic system and the tectonic evolution of Lipari volcanic island located in the southern Italy subduction zone. To do this we carried out a passive seismic experiment between October and November 2018 on Lipari, the largest of the Aeolian Archipelago (Di Luccio et al., 2019). 48 ZLand 3C seismic nodes were positioned on the island and recorded more than 300 Gbytes of data. The Aeolian Islands consist of a 150-km long ENE-WSW oriented volcanic arc and are located on 15 to 20 km of continental crust between the southern Tyrrhenian back arc basin and the Calabrian Arc. From NE to SW the arc-shaped alignment of Stromboli, Panarea, Salina, Filicudi and Alicudi is bisected by the NNW-SSE oriented Lipari and Volcano islands. The major strike-slip Tindari-Letojanni fault (TLf) is also NNW-SSE oriented, and crosses Lipari and Vulcano as it stretches southward to the northeastern tip of Sicily.
In the central Tyrrhenian Sea the volcanic activity started during Pliocene and migrated southeastward towards the Calabrian Arc and the ages of the volcanic products range from 1.3 Myr to the present. In the central Aeolian Islands, the volcanism started 0.4 Ma and fumaroles, hot springs and shallow seismicity characterize the volcanic islands and submerged areas, which are both assumed to be directly controlled by the TLf system. Also the main eruptive vents are aligned along the NNW-SSE direction. In western Lipari, geothermal and actively degassing areas as well as fumaroles are concentrated on fractures and faults, where kaolin formed due to the hydrothermal activity on pre-existing lava flows and pyroclastic and lacustrine deposits. A recent study (Cucci et al., 2017) has shown that a decrease in fluid discharge may reflect pressurization at depth that potentially precedes hydrothermal explosions. In this regards a primary goal is to understand the influence on the regional tectonics on the volcanic evolution of Lipari. In this study we aim to build an accurate catalog of the local seismicity by analyzing the recorded waveforms and computing focal mechanisms to characterize the spatial extent of the TLf. Analysis of the seismicity in frequency and time domains will allow us to investigate the interaction between the Lipari's hydrothermal system and volcanism in the framework of the Tyrrhenian subduction zone.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.V13D0190D
- Keywords:
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- 1295 Integrations of techniques;
- GEODESY AND GRAVITY;
- 7280 Volcano seismology;
- SEISMOLOGY;
- 8178 Tectonics and magmatism;
- TECTONOPHYSICS;
- 8485 Remote sensing of volcanoes;
- VOLCANOLOGY