Publication Date:
2017-04-04
Description:
We present results from the first crustal seismic tomography for the southern Tyrrhenian area, which includes ocean bottom seismometer (OBS) data and a bathymetry correction. This area comprises Mt. Etna, the Aeolian Islands, and many volcanic seamounts, including the Marsili Seamount. The seismicity distribution in the area depends on the complex interaction between tectonics and volcanism. The 3-D
velocity model presented in this study is obtained by the inversion of P wave arrival times from crustal earthquakes. We integrate travel time data recorded by an OBS network (Tyrrhenian Deep Sea Experiment), the SN-1 seafloor observatory, and the land network. Our model shows a high correlation
between the P wave anomaly distribution and seismic and volcanic structures. Two main low-velocity anomalies underlie the central Aeolian Islands and Mt. Etna. The two volumes, which are related to the
well-known active volcanism, are separated and located at different depths. This finding, in agreement with structural, petrography, and GPS data from literature, confirms the independence of the two systems.
The strongest negative anomaly is found below Mt. Etna at the base of the crust, and we associate it with the deep feeding system of the volcano. We infer that most of the seismicity is generated in brittle rock
volumes that are affected by the action of hot fluids under high pressure due to the active volcanism in the area. Lateral changes of velocity are related to a transition from the western to the central Aeolian Islands and to the passage from continental crust to the Tyrrhenian oceanic uppermost mantle.
Description:
Published
Description:
3703–3719
Description:
1.4. TTC - Sorveglianza sismologica delle aree vulcaniche attive
Description:
3.3. Geodinamica e struttura dell'interno della Terra
Description:
JCR Journal
Description:
open
Keywords:
ocean bottom seismometers
;
southern Tyrrhenian Sea
;
seismic tomography
;
Aeolian Islands
;
Etna
;
oceanic continental crust
;
04. Solid Earth::04.06. Seismology::04.06.06. Surveys, measurements, and monitoring
;
04. Solid Earth::04.06. Seismology::04.06.07. Tomography and anisotropy
;
04. Solid Earth::04.07. Tectonophysics::04.07.04. Plate boundaries, motion, and tectonics
;
04. Solid Earth::04.07. Tectonophysics::04.07.06. Subduction related processes
;
04. Solid Earth::04.07. Tectonophysics::04.07.07. Tectonics
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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