HR: 1340h
AN: V53B-1574    [Abstracts]
TI: Tomographic Images of Volatile Rich Magma Intrusions Leading to the 2001 and 2002-2003 Mt. Etna Eruptions
AU: * Cocina, O
EM: cocina@ct.ingv.it
AF: Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Catania, Piazza Roma, 2, Catania, CT 95123 Italy
AU: Barberi, G
EM: barberi@ct.ingv.it
AF: Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Catania, Piazza Roma, 2, Catania, CT 95123 Italy
AU: Patane', D
EM: patane@ct.ingv.it
AF: Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Catania, Piazza Roma, 2, Catania, CT 95123 Italy
AU: Chiarabba, C
EM: chiarabba@ingv.it
AF: Istituto Nazionale di Geofisica e Vulcanologia, CNT, Sezione di Roma, Via di Vigna Murata, 605, Roma, RM 00143 Italy
AU: De Gori, P
EM: degori@ingv.it
AF: Istituto Nazionale di Geofisica e Vulcanologia, CNT, Sezione di Roma, Via di Vigna Murata, 605, Roma, RM 00143 Italy
AB: Seismic monitoring with proper sampling in space and time, and repeated tomographic analysis (4-D tomography) on active volcanoes, can be considered useful tools for the detection of volatile-rich magma intrusions, responsible of explosive eruptions. Seismic Vp/Vs tomographic images at depth less than 5 km b.s.l., obtained analyzing 2001 and 2002-2003 Mt. Etna eruptions datasets, highlights both volumes where gas-saturated magma intrusion occurred (Vp/Vs negative anomalies) and regions enriched in fluids (Vp/Vs positive anomalies). The 4D images of the Vp/Vs velocity ratio suggest that these eruptions can be related to intrusions of volatile-rich basaltic magma emplaced some months before their onset, as supported by recent seismological, geodetic and geochemical evidences. These results constitute the first unambiguous detection of Vp/Vs changes at Mt. Etna volcano, representing a possible tool to recognize high level of explosive eruptions.
DE: 7270 Tomography (6982, 8180)
DE: 7280 Volcano seismology (8419)
DE: 8414 Eruption mechanisms and flow emplacement
DE: 8419 Volcano monitoring (7280)
SC: Volcanology, Geochemistry, Petrology [V]
MN: Fall Meeting 2005