Publication Date:
2017-04-04
Description:
Flank instability at basaltic volcanoes is often related to repeated dike intrusions along
rift zones and accompanied by surface fracturing and seismicity. These processes have been
mostly studied during specific events, and the lack of longer-term observations hinders their
better understanding. Here we analyze ~20 years of deformation of the Pernicana Fault
System (PFS), the key structure controlling the instability of the eastern flank of Mt. Etna.
We exploit East-West and vertical components of mean deformation velocity, as well as
corresponding time series, computed from ERS/ENVISAT (1992–2010) and COSMO-SkyMed
(2009–2011) satellite radar sensors via Synthetic Aperture Radar Interferometry techniques.
We then integrate and compare this information with field, seismic, and leveling data,
collected between 1980 and 2012. We observe transient displacements accompanied by
seismicity, overprinted on a long-term background eastward motion (~2 cm/yr). In the last
decades, these transient events were preceded by a constant amount of accumulated strain
near the PFS. The time of strain accumulation varies between a few years and a few decades,
also depending on magma emplacement within the nearby North East Rift, which may
increase the strain along the PFS. These results suggest that the amount of deformation near
the PFS may be used as a gauge to forecast the occurrence of instability transients on the
eastern flank of Etna. In this context, the PFS may provide an ideal, small-scale structure to
test the relations between strain accumulation, stress loading, and seismic energy release.
Description:
This work has been partially supported by the
Italian Space Agency (ASI) within the SAR4Volcanoes project, agreement I/
034/11/0.
Description:
Published
Description:
4398-4409
Description:
1T. Geodinamica e interno della Terra
Description:
2T. Tettonica attiva
Description:
3T. Pericolosità sismica e contributo alla definizione del rischio
Description:
4T. Fisica dei terremoti e scenari cosismici
Description:
5T. Sorveglianza sismica e operatività post-terremoto
Description:
1V. Storia e struttura dei sistemi vulcanici
Description:
2V. Dinamiche di unrest e scenari pre-eruttivi
Description:
3V. Dinamiche e scenari eruttivi
Description:
4V. Vulcani e ambiente
Description:
6A. Monitoraggio ambientale, sicurezza e territorio
Description:
JCR Journal
Description:
restricted
Keywords:
Volcano flank instability
;
Pernicana fault
;
Etna
;
04. Solid Earth::04.01. Earth Interior::04.01.99. General or miscellaneous
;
04. Solid Earth::04.03. Geodesy::04.03.99. General or miscellaneous
;
04. Solid Earth::04.04. Geology::04.04.99. General or miscellaneous
;
04. Solid Earth::04.04. Geology::04.04.09. Structural geology
;
04. Solid Earth::04.06. Seismology::04.06.99. General or miscellaneous
;
04. Solid Earth::04.07. Tectonophysics::04.07.99. General or miscellaneous
;
04. Solid Earth::04.08. Volcanology::04.08.99. General or miscellaneous
;
05. General::05.01. Computational geophysics::05.01.99. General or miscellaneous
;
05. General::05.02. Data dissemination::05.02.99. General or miscellaneous
;
05. General::05.08. Risk::05.08.99. General or miscellaneous
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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