Publication Date:
2024-05-29
Description:
Fault creep along the lower eastern flank of Mt. Etna volcano has been documented since the end of the 19th
century and significantly contributes to the surface faulting hazard in the area. On 29 October 2002, during a
seismic swarm related to dyke intrusions, two earthquakes caused extensive damage and surface faulting in an
area between the Santa Venerina and Santa Tecla villages. On the same day after the two earthquakes, an
episodic aseismic creep occurred along the Scalo Pennisi Fault close to the Santa Tecla coastline. On 8 February
2022, during another aseismic creep event along the Scalo Pennisi Fault, we observed the reopening of the pre existing 2002 ground ruptures mostly as pure dilational fractures. We mapped the 2002 and 2022 surface
ruptures, and collected data on displacement, length, and pattern of ground breaks. Ground ruptures affected
structures located along the activated fault segments, including roads, walls and buildings. The 2002 surface
faulting propagation can be ascribed to a sliding of the Mt. Etna eastern flank toward the SE, as also suggested by
the related shallow seismicity, and InSAR and geodetic data between 2002 and 2005. For the 2022 event, dif ferential InSAR data, acquired in both descending and ascending views, allowed us to decompose Line of Sight
(LOS) displacement into horizontal and vertical components. We detect a ~ 700 m long and ~ 500 m wide
deformation zone with a downward and eastward motion (max displacement ~1,5 cm) consistent with a normal
fault. We inverted the InSAR–detected surface deformation using a uniform-slip fault model and obtained a
shallow detachment for the causative fault, located at ~300 m depth, within the volcanic pile. This is the first in depth study along the Scalo Pennisi Fault to suggest a shallow faulting that accommodates Mt. Etna E flank
gravitational sliding.
Description:
Published
Description:
229829
Description:
JCR Journal
Keywords:
Etna
;
Aseismic creep
;
Earthquake
;
Surface faulting
;
Volcano-tectonic deformation
;
InSAR
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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