Publication Date:
2021-11-29
Description:
In the recent decades, satellite monitoring techniques have enhanced the discovery of non-catastrophic slope movements triggered by earthquake shaking involving old paleo-landslides with deep-seated sliding surfaces. Understanding the triggering and attenuation mechanisms of such mass movements is crucial to assessing their hazard. In December 2018, Etna volcano (southern Italy) began a very intense eruption, which was accompanied by a seismic swarm with magnitudes reaching 4.9. Synthetic aperture radar data identified local displacements over a hilly area to the west of Paternò village. We evaluated the contribution of seismically induced surface instability to the observed ground displacement by employing a multidisciplinary analysis comprising geological, geotechnical and geomorphological data, together with analytical and dynamic modelling. The results allowed us to identify the geometry and kinematics of a previously unknown paleo-landslide, which was stable before the volcanic eruption. The landslide was triggered by the light-to-moderate seismic shaking produced by the strongest event of the seismic sequence, namely, the December 26, Mw 4.9 earthquake. This observation confirms that seismic shaking has a cumulative effect on landslides that does not necessarily manifest as a failure but could evolve into a catastrophic collapse after several earthquakes.
Description:
Published
Description:
112524
Description:
5T. Sismologia, geofisica e geologia per l'ingegneria sismica
Description:
JCR Journal
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
