Tyrrhenian Sea

I picked a pomegranate from a tree once, on Stromboli, an island in the Tyrrhenian Sea, off the coast of Italy. It looked like something from another planet, especially when you cut it open—a seed pod from another world. A world, like Stromboli, where you watch... 

Capaldi G, Cortini M, Pece R (1982) Th isotopes at Vesuvius evidence for open-system behavior of magma-forming processes. J Volcanol Geotherm Res 14 247-260 Capaldi G, Cortini M, Pece R (1983) U and Th decay-series disequilibria in historical lavas from the Eolian islands, Tyrrhenian Sea. Isot Geosci 1 39-55... 

Barghigiani, C. and S. De Ranieri. 1992. Mercury content in different size classes of important edible species of the northern Tyrrhenian Sea. Mar. Pollut. Bull. 24 114-116. 

Barghigiani, C., D. Pellegrini, and E. Carpene. 1989. Mercury binding proteins in liver and muscle of flat fish from the northern Tyrrhenian Sea. Comp. Biochem. Physiol. 94C 309-312. 

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. 

Tyrrhenian Sea Floor (12 Ma to Present) Comacya (12), Magnaghi (3), Mar-sili (1.8-0), Vavilov, Aceste, Anchi-se, Lametini, Palinuro, older Ponza, etc. - Coexisting intraplate (oceanic tholeiites, Na-transitional and alkaline) and arc-type (arc-tholeiitic, calc-alkaline, potassic) rocks. 

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. 

Several volcanoes with calc-alkaline, tholeiitic (MORB and arc tholeiites) to Na-transitional and alkaline affinity coexist on the Tyrrhenian Sea floor. According to some authors (Savelli 1988 Locardi 1993), the calc-alkaline and shoshonitic seamounts developed along arcuate structures that become younger from west to south-east. The older volcanic cycle (4.5 Ma) of Ponza Island may represent the northern end of one of these arcs. 

Silicic volcanics occur as lavas at San Vincenzo, Roccastrada, Monte A-miata, Monti Cimini and Tolfa-Manziana-Cerite complex. Pyroclastic rocks are scarce or absent, and a few ignimbrites only occur at Monti Cimini and Cerite complex. Silicic intrusions crop out in the islands of Elba, Montecristo and Giglio, and at Campiglia and Gavorrano in southern Tuscany. Other granitoid bodies occur as seamounts in the northern Tyrrhenian Sea (e.g. Vercelli Barbieri et al. 1986) and as hidden intrusions in several places of southern Tuscany (e.g. Franceschini et al. 2000 Poli et al. 2003). 

The volcanoes of the Roman Province developed in a region characterised by Late Miocene-Quaternary extensional tectonics related to the eastward migration of Apennine mountain range and to the contemporaneous opening of the Tyrrhenian Sea. The volcanic zone is characterised by a system of Upper Miocene to Pleistocene NW-SE basins, developed along normal faults and intersected by strike-slip NE-SW faults (Bartolini et al. 1982). Both fault systems represent zones of crustal weakness along which Roman potassic magmas were intruded. 

As other sectors of the Apennine chain, central Apennines have been affected by various tectonic phases. Compressional events dominated from Upper Cretaceous to Lower Pliocene and generated fragmentation of the carbonate platform and intensive thrusting and folding. Extensional tectonics dominated from Middle Pliocene to present. It initially affected the Tyrrhenian Sea border and successively shifted eastward, generating intensive NW-SE faulting with development of graben-horst systems. 

The volcanic centers of the Campania Province developed inside Quaternary extensional basins along the Tyrrhenian Sea border at the intersection between NE-SW and NW-SE fault systems. The Pontine Islands form a row of volcanoes with a W-E trend, offshore the Campania Province, and along the so-called 41st Parallel Tectonic Line (Serri 1990 Bruno et al. 2000). Vulture is located at the eastern border of the Apennine compression front, in an extensional tectonic setting affecting the border of the Apulia foreland. 

The thickness of the lithosphere along the Pontine-Campania-Vulture transect increases from about 50 km along the Tyrrhenian Sea border to more than 110 km in the Apulia foreland (Calcagnile and Panza 1981). The depth of the Moho increases from about 20-25 km offshore the Tyrrhenian Sea coast to 40 km beneath the internal zones of the Apennines, to decrease to about 30 km beneath the Apulia foreland (e.g. Locardi and Nicolich 1988 Piromallo and Morelli 2003). In contrast with other zones of the Apennine chain, the sector running from the Campania Province to... 

The Aeolian archipelago is an active volcanic arc in the southern Tyrrhenian Sea (Keller 1982). It consists of several stratovolcanoes forming seven main islands and several seamounts, which extend to the west and northeast of the emergent portion of the arc, around the Marsili basin (Fig. 7.1). The volcanic activity exposed above the sea level took place entirely during the Quaternary, most probably from about 400 ka to the present (Gillot 1987). 

The Ustica island (0.75-0.13 Ma) occurs in the southern Tyrrhenian Sea, west of the Aeolian volcanic arc, along the southern margin of the Tyrrhenian abyssal plain, probably at the intersection between E-W and NW-SE trending faults (e.g. Boccaletti et al. 1984). The recently discovered Pro-meteo submarine lava field is located a few km southeast of Ustica (Trua et al. 2003). 

Information on ages and on petrological and volcanological characteristics of Plio-Quatemary Sardinian and southern Tyrrhenian Sea volcanoes is given in Tables 9.1 and 9.2. Selected analyses are given in Tables 9.3 and 9.4. The locations of the main eruptive centres are shown in Fig. 9.1. 

Fig. 9.1. Distribution of Plio-Quatemary volcanism in the southern Tyrrhenian Sea and Sardinia. The Oligo-Miocene arc-type magmatism of Sardinia is also reported.

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