0000000000284100
AUTHOR
Sulli A.
Understanding paleomagnetic rotations in Sicily: thrust vs. strike-slipe tectonics
The paleomagnetic investigation of the western Sicily Maghrebian belt has revealed since the 1970s that large clockwise (CW) rotations up to 140° with respect to the Hyblean-African foreland occurred synchronous with Tertiary shortening of the chain. The observation that rotations decrease stepwise from internal to external tectono-stratigraphic units led in the 1990s to a widely accepted model postulating that rotational thrust-sheet emplaced during forward orogenic propagation. More recently, other authors suggested that CW rotations from Sicily are conversely the result of late orogenic dextral strike-slip tectonics. Here we report on a paleomagnetic investigation of 30 Jurassic-Eocene s…
SEISMOTECTONIC MAP OF THE NORTHERN SICILY CONTINENTAL MARGIN (NSCM) AND IMPLICATIONS FOR GEOHAZARD ASSESSMENT
The Sicily dominates the central Mediterranean Sea. The Northern Sicily Continental Margin (NSCM) is a segment of the Appeninic-Tyrrhenian System whose upbuilding refers to both the postcollisional convergence between Africa and a very complex “European” crust (Bonardi et al., 2001) or AlKaPeKa (sensu Boullin, 1986) and the opening of the Tyrrhenian back-arc basin. Seismostratigraphic and structural analysis of a large number of available (from ViDePi project) and unpublished (from Department of Earth and Marine Science of the University of Palermo) multichannel seismic reflection profiles acquired across the NSCM, allow us to produce an accurate seismotectonic map, in order to obtain a use…
Computation of run-up heights for landslide-generated tsunami. An attempt of hazard assessment in the North Sicily continental margin
The North Sicily continental margin is a very active region located in a transitional area between the Sicilian- Maghrebian Chain to the south and the southern Tyrrhenian Sea to the north. Strong seismicity, active tectonics and volcanism, fluid escape, high sediment supply and widespread mass movements exposed this region to marine geohazards, with a potential for tsunami generation (e.g. Messina 1908, Stromboli 2004 events). In recent years, high resolution swath mapping and high resolution to high penetration seismic reflection profiles have been collected during several oceanographic cruises, in the frame of the MaGIC and CARG projects. Morphobatymetric and geoseismic analysis evidenced…
Sismotettonica del Margine Continentale della Sicilia nord-occidentale: implicazioni per la valutazione del geohazard
I processi tettonici attivi nel margine continentale della Sicilia settentrionale (MCSS) sono stati analizzati per la realizzazione della carta sismotettonica, al fine di ottenere uno strumento utile per la valutazione della pericolosità sismica della regione. La carta sismotettonica è realizzata attraverso la sovrapposizione di layer che rappresentano la distribuzione di tematismi, quali litostratigrafia, tettonica, sismicità, flussi di calore, gravimetria, magnetometria, profondità della Moho, movimenti orizzontali e verticali, frane, fuoriuscite di fluidi, evidenziando la relazione tra questi e le strutture attive. Il MCSS si trova in una zona di transizione tra la catena siciliano-maghr…
Seismostratigraphic reconstruction of the Messinian palaeotopography across the Northern Sicily Continental Margin (NSCM) and an overlying Zanclean megaflood deposit
During the Messinian salinity crisis (MSC) (from 5.97 to 5.33 Ma), the Mediterranean Sea became disconnected from the world’s oceans and a fast and continuous evaporation resulted in its partial desiccation. One of the theories for the end of the MSC postulates that a large volume of Atlantic waters entered the Mediterranean Sea through the Gibraltar Strait and rapidly refilled the Mediterranean basin in an event welldocumented known as the Zanclean Flood. The pathway of the Zanclean flood during its passage from the western to the eastern Mediterranean Sea is unclear. The aim of this study is to understand the effects of the Messinian palaeotopography of the southern Tyrrhenian Sea on the …
3D structural modeling and restoration in fold-and-thrust belts: examples from the Kumeta and Busambra Mts., NW Sicily (Italy)
The Sicilian Fold and Thrust belt (SFTB) is a structurally complex area where along-strike variations of structural styles, shortening amounts, exhumation rates and amounts of syn-tectonic sedimentation frequently occur. Moreover strong differential clockwise rotations around vertical axes affected the different tectonic units during their emplacement. This complexity, coupled with debatable or incomplete subsurface dataset (e.g., available 2D onshore seismic lines) allowed previous authors to propose different interpretations for the tectonic evolution of the SFTB since Cenozoic time. The study area, located in the Western sector of the SFTB comprises the Kumeta and Busambra ridges (derive…
Multivariate modelling of geophysical tomography data to identify a tectonized area
An integrated analysis approach, based on geological investigations and 2D high-resolution shallow geophysical data, was proposed along a slope in the Bellolampo landfill area (Palermo, Italy) where the presence of a fault zone was hypothesized. Geophysical surveys included electrical resistivity tomography (ERT), induced polarization tomography (IPT) and seismic refraction tomography (SRT) techniques. The inversion of single geophysical parameter often does not allow to justify the complexity of the subsoil structures. The most appropriate solution should be to add additional physical or geological information so to get a constrained geological model. However, it is not at all easy to work…