Mt. Vesuvius is a worldwide known active volcano located in Southern Italy, east of the city of Napoli. Its last eruption occurred in 1944, ending a continuous open-conduit activity that lasted for more than three centuries. After then the volcano entered into a quiescent phase. Nonetheless, the explosive style of its past activity and its proximity to densely populated areas make Mt. Vesuvius one of the most dangerous volcanoes in the world. For this reason, a comprehensive monitoring program was established, with the goal of early detection of any possible signals of unrest. During the last decades, seismic activity at Vesuvius has been characterized by low-magnitude volcanotec- tonic (VT) earthquakes located below the crater area at depths shallower than 5 km (D’Auria et al., 2013). Some degassing activity is observed at fumaroles inside the crater (Granieri et al., 2013), whereas ground deformations are negligible and attributed to gravitation flank sliding and compaction rather than volcanic activity (Tammaro et al., 2013). Should the volcano reawake in the future, a number of precursor phenomena are expected to be observed. Among them, seismic activity is the most common precursor observed at volcanoes worldwide before eruptions. Seismic events different than VT earthquakes, like volcanic tremor and low-frequency earthquakes (LF), have been documented to accompany unrest episodes at many active volcanoes worldwide (Konstantinou and Schlindwein, 2002; Chouet, 2003; McNutt, 2005; Chouet and Matoza, 2013). The source of such signals is likely related to the volcano feeding system, as a consequence of the interaction of volcanic and hydrothermal fluids with the surrounding rock (e.g., Chouet, 1996). Unfortunately, the distinctive features of volcanic tremor and LF earthquakes make their detection, classification, and location a challenging task. These events are in fact characterized by low amplitudes, emergent onset, and lack of impulsive phases, which prevent the use of location methods based on the inversion of arrival times determined at the stations of a local seismic network.
Seismic monitoring of Mt. Vesuvius by array methods
LA ROCCA, MARIO;
2014-01-01
Abstract
Mt. Vesuvius is a worldwide known active volcano located in Southern Italy, east of the city of Napoli. Its last eruption occurred in 1944, ending a continuous open-conduit activity that lasted for more than three centuries. After then the volcano entered into a quiescent phase. Nonetheless, the explosive style of its past activity and its proximity to densely populated areas make Mt. Vesuvius one of the most dangerous volcanoes in the world. For this reason, a comprehensive monitoring program was established, with the goal of early detection of any possible signals of unrest. During the last decades, seismic activity at Vesuvius has been characterized by low-magnitude volcanotec- tonic (VT) earthquakes located below the crater area at depths shallower than 5 km (D’Auria et al., 2013). Some degassing activity is observed at fumaroles inside the crater (Granieri et al., 2013), whereas ground deformations are negligible and attributed to gravitation flank sliding and compaction rather than volcanic activity (Tammaro et al., 2013). Should the volcano reawake in the future, a number of precursor phenomena are expected to be observed. Among them, seismic activity is the most common precursor observed at volcanoes worldwide before eruptions. Seismic events different than VT earthquakes, like volcanic tremor and low-frequency earthquakes (LF), have been documented to accompany unrest episodes at many active volcanoes worldwide (Konstantinou and Schlindwein, 2002; Chouet, 2003; McNutt, 2005; Chouet and Matoza, 2013). The source of such signals is likely related to the volcano feeding system, as a consequence of the interaction of volcanic and hydrothermal fluids with the surrounding rock (e.g., Chouet, 1996). Unfortunately, the distinctive features of volcanic tremor and LF earthquakes make their detection, classification, and location a challenging task. These events are in fact characterized by low amplitudes, emergent onset, and lack of impulsive phases, which prevent the use of location methods based on the inversion of arrival times determined at the stations of a local seismic network.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
