Sicily Channel

TMPC pipeline for the import of Algerian gas, made up of two lines each 156-kilometer long and three lines each 155-kilometer crossing underwater the Sicily Channel from Cap Bon to Mazara del Vallo in Sicily, the entry point to Italy. 

Plio-Quatemary magmatism in Italy occurs along a NW-SE trending ex-tensional zone on the Tyrrhenian border of the Italian peninsula, in western Sicily, in the Sicily Channel, on the Tyrrhenian Sea floor and in Sardinia. Geochronological data for the main magmatic centres (Fig. 1.1 Table 1.1) show that there is a general decrease in age from Tuscany and Sardinia towards the south-east, where volcanism is presently active. 

Sicily (7 Ma to Present) Etna (0.5-Present), Iblei (7-1.5), U-stica (0.75-0.13), Pantelleria (0.3-0.005), Linosa (1-0.5), Sicily Channel seamounts - Stratovolcanoes, diatremes, small plateaux, etc. formed of tholeiitic and Na-alkaline rocks (basanite, hawaiite, trachyte, peralkaline trachyte and rhyolite). 

Flegrei and Ischia) and continues in the Aeolian islands, in eastern Sicily (Etna), and along the Sicily Channel. Young volcanism in Sardinia has ages of about 5 to 0.1 Ma. Several Pliocene to active seamounts occur on the Tyrrhenian Sea floor. 

Tuscany shoshonitic basalt Sicily Channel transitional basalt A Tuscany famproite Etna Na-alkaline basalt... 

The volcanoes of the Sicily Channel (Linosa and Pantelleria and a number of seamounts Miocene to present in age) are mainly located along ex-... 

Crustal thickness in the Sicily volcanic province is about 20 to 25 km (Boccaletti et al. 1984 Him et al. 1997 Nicolich 2001, and references therein). The lithosphere shows variable thickness from about 50 km beneath the Ustica island, to 60 km beneath the Sicily Channel and some 70 km in the Etna and Iblei area (Calcagnile et al. 1982). Heath flow is about 50 to 70 mW/m2 at the regional scale but is higher than 80-100 mW/m2 in the areas affected by recent magmatism (Della Vedova et al. 2001). 

Sicily Channel Miocene to - Several cones (Cimotoe, Tetide, Anfitrite, Graham,... 

Fig. 8.16. TAS classification diagrams of Linosa and Sicily Channel seamounts. The dashed line is the boundary between subalkaline and alkaline fields of Irvine and Baragar (1971). Data on seamounts have been recalculated on water-free basis.

Numerous volcanic centres occur on the seafloor of the Sicily Channel (Fig. 8.1). Calanchi et al. (1989) recognised at least ten recent submarine volcanoes of various dimensions, mostly located along NW-SE regional faults. Some of these volcanoes have erupted during historical times others are covered by undisturbed Pliocene-Quaternary sediments and have been detected by seismic profiles and magnetic survey (Allan and Morelli 1971). 

Finally, the most recent centre in the Sicily Channel is the Foerstner volcano sited about 5 km north-west of Pantelleria. This is reported to have erupted in October 1881. The eruption lasted about a week, but was not observed by any scientist and descriptions are based on fishermen accounts (Washington 1909). 

Trace element abundances of rocks dredged from the Sicily Channel seamounts are scarce (Beccaluva et al. 1981 Calanchi et al. 1989). They show variable concentrations, with incompatible element abundances increasing from tholeiitic to alkaline basalts and basanites (Fig. 8.17). Mantle normalised incompatible elements define bell-shaped patterns (not shown), which resemble those for the exposed rocks in the Sicily Channel. 

Extensional and strike-slip faulting in Sicily and the Sicily Channel, with formation of tholeiitic to Na-alkaline volcanism. 

Rossi PL, Tranne CA, Calanchi N, Lanti E (1996) Geology, stratigraphy and vol-canological evolution of the island of Linosa (Sicily Channel). Acta Vulcanol 8 73-90... 

Parello F., Allard P., D Alessandro W., Federico C., Jean-Baptiste P., and Catani O. (2000) Isotope geochemistry of Pantelleria volcanic fluids, Sicily Channel rift a mantle volatile end-member for volcanism in southern Europe. Earth Planet. Sci. Lett. 180, 325-339. 

The map in Fig. 1.5 represents the geographical distribution of accidents and illustrates the accident-prone areas in the Mediterranean, namely the approaches of Gibraltar and the Malta-Sicily channel and accesses around the areas of Genoa and Leghorn, Venice and Trieste, Piraeus, Beirut, and Alexandria. 

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