GNGTS 2016 - Atti del 35° Convegno Nazionale

188 GNGTS 2016 S essione 1.1 Fig. 1 – Geological sketch map of the Catania region, eastern Sicily. Key: (1) Holocene deposits (a) Late Würmian- Holocene alluvial fan (b); (2) Etnean Lavas: recent alkaline products (80 ka to Present) (a); ancient alkaline products (180-100 ka) (b) (chronological data from Gillot et al. , 1994); (3) sub-alkaline products of Mt. Etna volcanic district (320-200 ka) (chronological data from Gillot et al. , 1994); (4) Middle Pleistocene foredeep deposits and Late Quaternary marine terraces; (5) Undifferentiated Meso-Cenozoic Maghrebian allochthonous units; (6) Pliocene-Early Pleistocene volcanics of the Hyblean Plateau; (7) Meso-Cenozoic foreland sequences of the Hyblean Plateau; (8) Late Quaternary and active tectonics and volcano-tectonics: strike-slip fault (a); normal fault of the “Siculo-Calabrian Rift Zone” (b), thrust (c), anticline (d) dry and eruptive fissure (e); (9) buried front of the Maghrebian allochthonous units; (10) Middle Pleistocene Hyblean extensional fault; (11) main transform fault zone; (12) maximum horizontal extension in the Etnean area and in the Ionian offshore; (13) maximum horizontal compression in the Catania Plain area; (14) main earthquake (a): in the map the major (M≥7) historical earthquakes are reported; the inset also shows the main instrumental events, with available focal mechanisms (b); (15) GPS vector; (16) rift-flank volcanoes (see inset a). The inset a shows the deformation belts connected to the active Nubia-Eurasia convergent boundary and the Siculo-Calabrian Rift Zone respectively. The inset b refers to the relative motion between the plates. (From Catalano et al. , 2011 mod.). substratum composed of a monotonous Early-Middle Pleistocene marly-clay succession, at places capped by few tens of meters of marine sands (Monaco et al. , 2000). This marine succession is exposed at the southeastern end of Catania (S. Giorgio in Fig. 2) where it form the SE dipping forelimb of a vast anticline, whose hinge zone is located in the area of Misterbianco (Fig. 2). The sedimentary substratum is severely uplifted and is modelled by a flight of marine terraced coastal clastic wedges, ranging in age from the OIS 7.5 (240 ka) to the OIS 3.1 (40 ka) (Monaco et al. , 2000; Catalano et al. , 2004). At places, the terraced successions also include the ancient (Middle Pleistocene) lava flows of the earlier activity of Mt. Etna. The terraced slope, which extends in a NE-SW direction from the southern periphery of Catania to the coast of Aci