Dynamics of the eastern flank of Mt. Etna volcano (Italy) investigated by a dense GPS network

A 2D finite elements study was carried out to analyse the effects caused by dike intrusion inside a heterogeneous medium and with a realistic topography of Mt. Etna volcano. Firstly, the method (dimension domain, elements type) was calibrated using plane strain models in elastic half-spaces; the results were compared with those obtained from analytical dislocation models. Then the effects caused both by the topographic variations and the presence of multi-layered medium on the surface, were studied. In particular, an application was then considered to Mt. Etna by taking into account the real topography and the stratification deduced from seismic tomography. In these conditions, the effects expected by the dike, employed to model the 2001 eruption under simple elastic half-space medium conditions, were computed, showing that topography is extremely important, at least in the near field.

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Relationship between seismicity and eruptive activity at Mt. Etna volcano (Italy) as inferred from historical record analysis: the 1883 and 1971 case histories

Annals of Geophysics ◽

10.4401/ag-3981 ◽

1996 ◽

Vol 39 (2) ◽

Author(s):

R. Azzaro ◽

M. S. Barbano

Keyword(s):

Seismic Activity ◽

Historical Record ◽

Effusion Rate ◽

Etna Volcano ◽

Case Histories ◽

Seismic Behaviour ◽

Volcanic System ◽

Prolonged Duration ◽

Mt Etna ◽

A Minor

In this paper historical and recent seismological data are analysed in order to investigate the relationship between seismicity and eruptive phenomena at Mt. Etna volcano. The 1883 and 1971 case histories have been proposed because they are significant events in the recent history of the volcano regarding volcanic hazard and show very different evolutions of associated seismic activity and eruption dynamics. The first (1883) represents flank eruptions characterised by high seismic release, short duration and moderate effusion rate whereas the second (1971) can be ascribed to eruptions starting as summit or subterminal events and thereafter developing on the flanks with a minor level of seismicity, higher effusion rate and prolonged duration. The pattern of seismic activity during 1883 and 1971, as inferred from historical record analysis, and the different associated type of eruption may be a result of diverse stress conditions acting on the volcanic system. The interpretation of the seismic behaviour by considering historical eruptions in a systematic fashion will contribute to a clearer understanding of volcanic phenomena at Mt. Etna.

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Detection of Volcanic Plumes by GPS: the 23 November 2013 Episode on Mt. Etna

Annals of Geophysics ◽

10.4401/ag-6622 ◽

2015 ◽

Vol 57 ◽

Author(s):

Massimo Aranzulla ◽

Flavio Cannavò ◽

Simona Scollo

Keyword(s):

Signal To Noise Ratio ◽

Explosive Eruptions ◽

Volcanic Plume ◽

Test Case ◽

Signal To Noise ◽

Volcanic Plumes ◽

Gps Network ◽

Mt Etna ◽

New Challenges ◽

Aviation Operations

<p>The detection of volcanic plumes produced during explosive eruptions is important to improve our understanding on dispersal processes and reduce risks to aviation operations. The ability of Global Position-ing System (GPS) to retrieve volcanic plumes is one of the new challenges of the last years in volcanic plume detection. In this work, we analyze the Signal to Noise Ratio (SNR) data from 21 permanent stations of the GPS network of the Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Etneo, that are located on the Mt. Etna (Italy) flanks. Being one of the most explosive events since 2011, the eruption of November 23, 2013 was chosen as a test-case. Results show some variations in the SNR data that can be correlated with the presence of an ash-laden plume in the atmosphere. Benefits and limitations of the method are highlighted.</p>

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Isochronal maps at Mt. Etna volcano (Italy): a simple and reliable tool for investigating large-scale heterogeneities

Annals of Geophysics ◽

10.4401/ag-3874 ◽

1997 ◽

Vol 40 (5) ◽

Author(s):

G. Patanè ◽

C. Centamore ◽

S. La Delfa

Keyword(s):

Large Scale ◽

Volcanic Edifice ◽

P Wave ◽

Etna Volcano ◽

Low Velocity ◽

Seismic Stations ◽

Arrival Times ◽

Mt Etna ◽

Wave Arrival ◽

Feeding Systems

This paper analyses twelve etnean earthquakes which occurred at various depths and recorded at least by eleven stations. The seismic stations span a wide part of the volcanic edifice; therefore each set of direct P-wave arrival times at these stations can be considered appropriate for tracing isochronal curves. Using this simple methodology and the results obtained by previous studies the authors make a reconstruction of the geometry of the bodies inside the crust beneath Mt. Etna. These bodies are interpreted as a set of cooled magmatic masses, delimited by low-velocity discontinuities which can be considered, at present, the major feeding systems of the volcano.

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The geodynamics of Mt. Etna volcano during and after the 1984 eruption

Annals of Geophysics ◽

10.4401/ag-3739 ◽

1999 ◽

Vol 42 (3) ◽

Author(s):

S. La Delfa ◽

G. Patanè ◽

C. Centamore

Keyword(s):

Complex Stress ◽

Focal Mechanisms ◽

Combined Effects ◽

Etna Volcano ◽

Locking Mechanism ◽

Mt Etna ◽

Complex Stress Field ◽

Seismic Networks ◽

Tectonic Forces ◽

The University

Data concerning M > 2.5 earthquakes that occurred at Mt. Etna volcano (Sicily, Italy) during the period April 15th - October 29th, 1984 are here presented and discussed. Only those events with reliable focal mechanisms (at least eight polarities) have been considered. Instrumental information comes from local seismic networks run by the University of Catania and the CNRS (Grenoble, France). The results obtained support the hypothesis that the seismicity and the volcanic activity at Mt. Etna are related to a complex stress field, due to the combined effects of the tectonics associated with the interaction between the African and Eurasian plates and the movement of magma into the crust. In particular, we hypothesize that the tectonic forces caused the end of the 1984 eruption, by means of a "locking mechanism".

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