Publication Date:
2015-02-25
Description:
An integrated analysis of large scale geological features and seismological data provides clues for a regionallyextended
structural discontinuity slicing through all over the central-eastern portion of the Sicilian Fold and Thrust Belt,
between the Madonie Mts. range and south of Mt. Etna region. Along this area, major NE-SW trending Mio-Pliocene
compressive structures (thrust-top basins and related syncline) are systematically dragged and rotated according to
vertical axis until to assume a hook-shape at their terminations. The clockwise sense of rotation of such major structures
suggests the occurrence of regional, more than 100 km long, dextral wrench fault zone with a NW-SE direction. More
detailed field surveys performed in key sectors (e.g. Madonie Mts. and Mt. Judica region) reveal that this crustal
discontinuity consists probably of a wider deformation band that in the near-surface scattered into a series of discrete
segments which sometimes overlap to form zone of releasing/restraining stopovers.
The analysis of the seismicity of the studied region helped us to achieve further information about the characteristics
of this shear zone. Selected earthquakes (from the CSI 1.1 1981–2002 by Castello et al., 2006, and from Bollettino
Sismico 2003-2012, http://bollettinosismico.rm.ingv.it/index.php), were used as data source for a simultaneous
inversion of a 3-D velocity structure and hypocentre parameters. The obtained velocity images and the foci distribution
depict a relevant NW-SE oriented tectonic boundary. This structural element splits a sector of high concentration of
earthquakes northwards from a zone with relative paucity of seismicity southward. Further, the possible presence of this
major structural discontinuity is emphasized by a strong wave velocity contrast found in central Sicily and visible down
to about 30 km of depth.
Description:
Published
Description:
http://www.geoscienze2014.it/
Description:
1T. Geodinamica e interno della Terra
Description:
open
Keywords:
regional shear zone
;
central-eastern Sicily
;
Tomography
;
04. Solid Earth::04.07. Tectonophysics::04.07.02. Geodynamics
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
Conference paper
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