GNGTS 2017 - 36° Convegno Nazionale
166 GNGTS 2017 S essione 1.2 Geohazards (Mediterranean Sea). In: S. Krastel, J.-H. Behrmann, D. V������ �� ������ �� ������� �� �������� �� ölker, M. Stipp, C. Berndt, R. Urgeles, J. Chaytor, K. Huhn, M. Strasser and C.B. Harbitz (Editors), Submarine Mass Movements and Their Consequences: 6th International Symposium. Springer International Publishing, Cham, pp. 295-306. DOI: 10.1007/978-3-319- 00972-8_26 Maesano, F.E., Tiberti, M.M. and Basili, R.; 2017: The Calabrian Arc: three-dimensional modelling of the subduction interface. Sci Rep, 7(1): 8887. DOI: 10.1038/s41598-017-09074-8 Volpi, V., Del Ben, A., Civile, D. and Zgur, F.; 2017: Neogene tectono-sedimentary interaction between the Calabrian Accretionary Wedge and the Apulian Foreland in the northern Ionian Sea. Marine and Petroleum Geology, 83: 246-260. DOI: 10.1016/j.marpetgeo.2017.03.013 GEOMETRICAL AND STRUCTURAL CONTROLS ON RUPTURE ZONE FABRIC: FIELD SURVEYS OF THE 2016 EARTHQUAKES IN SIBILLINI MOUNTAINS (CENTRAL ITALY) M. Menichetti, E. Tirincanti, D. Piacentini, M. Roccheggiani, A. Tamburini Dipartimento di Scienze Pure e Applicate, Università di Urbino, (PU), Italy A detailed field mapping of spatial geometries of the coseismic surface ruptures of active faults is the basis for the identification of seismogenic structures and represent an important step toward assessing the recurrence intervals and magnitude of earthquakes. Structural relations such fracture length and distributions, fault offsets, shear zone width, links between geometries along the fault strands provide insight into mechanics of earthquake rupture. Moreover surface ruptures display key structural relationships that are the essential tools for extrapolating and constraining the depth of the fault plane from a kinematic point of view. Kinematic fault analysis integrated with geophysical data, allowing to constrain any seismotectonic model. Integration of geological and seismological data remains one of the main objectives when identifying active faults and assessing their potential hazard. While large data sets of instrumental seismological data are easy to gather, especially with modern digital seismic stations, field geological data remain very costly in terms of human and economic resources, especially in remote areas. However, evolving technologies have allowed remotely sensed data to be used to obtain a lot of equivalent information. Asignificant sequence of earthquakes occurred in the SibilliniMountains inCentral Italy from August to October 2016. On August 24, Mw 6.1 earthquake struck the area between the town of Amatrice (Rieti Province) and Arquata del Tronto (Ascoli Piceno Province). Several ground ruptures along different strands of SW dipping extensional faults occurred over a distance of more than 20 km, throughout the morphologically complex landscape of the Sibillini Mountain chain and the Laga massif. The October 26 Mw 6.0 earthquake was centred in the Visso area (Macerata Province), approximately 30 km northwest of the previous event. On October 30, an Mw 6.5 event occurred near Norcia (Perugia Province), in an area located between the epicentres of the former earthquakes. This event reactivated existing ground ruptures and produced further rupturing over a larger area. A highly detailed map of the coseismic surface ruptures was created by integrating a direct and a classical structural field survey with low altitude aerial photos and remote sensing data interpretation. An important challenge in the field survey was related to the easy and rapid erosional degradation of fault scarps especially in a mountain range where storms are frequents and the snow cover can reach few meters. The exposed coeseismic rupture surfaces begins degradation immediately after the earthquake, and, within a period as short as a few weeks, many important structural relationships of the surface rupture may have become completely erased and cannot be documented at any scale. ������� ������� ����� �� ���������� ������� �� Rupture mapping based on low-flying flights of
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