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THE SOUTHERN TYRRHENIAN SEA MARGIN 503

The recognition of the STSSD as the dominant structure REFERENCES
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NW-SE directed convergence. Analysis of NW-SE trend- BOUCHER C., ALTAMINI Z. & SILLARD P. (1998) - Results and Analysis
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of the ITRF97. IERS Technical note, 27, Central Bureau of
odds with previous purely extensional models (e.g. see IERS, Paris Observatory.
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Sea margin can be interpreted in terms of strike-slip tec- inheritance in mountain belts: an Alpine-Apennine perspective.
tonics. The main structure has the geometry of a dextral Journal of Structural Geology, 28, 1893-1908.
strike-slip fault system, that we indicate as the Southern CALAIS E., GALISSON L., STEPHAN J-F., DELTEIL J., DEVERCHERE J.,
Tyrrhenian Strike-Slip Duplex (STSSD: see also RENDA LARROQUE C., MERCIER D., DE LEPINAY B., POPOFF M. & SOS-
et alii, 1999). This structure, along with its westward con- SON M. (2000) - Crustal strain in the southern Alps, 1948-1998.
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represents a key-feature in the framework of the geody- CARMINATI E., WORTEL M.J.R., SPAKMAN W. & SABADINI R. (1998) -
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namic history of the western Mediterranean system. Mediterranean basins. Some geological and geophysical evidence.
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of the southern Tyrrhenian Sea margin, our study has a CARTER W.E. & ROBERTSON D.S. (1986) - Studying the Earth by Very
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ACKNOWLEDGEMENTS
DE VOOGD B., TRUFFERT C., CHAMOT-ROOKE N., HUCHON P., LALLE-
Discussions with P. Rutigliano, R. Devoti, C. Sciarretta, V. Luceri, MANT S. & LE PICHON X. (1992) - Two-ship deep seismic soun-
F. Vespe and P. Tomasi were very helpful. The European Community dings in the basins of the Eastern Mediterranean Sea (Pasiphae
supported this study (Research Networks, «Measurement of Vertical cruise). Geophysical Journal International, 109, 536-552.
Crustal Motion in Europe by VLBI»), grant ERB-FMRX-CT9960071. DEVOTI R., FERRARO C., LANOTTE R., LUCERI V., NARDI A., PACIONE R.,
This paper is dedicated to the memory of Mario Grasso, whose semi- RUTIGLIANO P., SCIARRETTA C., GUEGUEN E., BIANCO G. &
nal work in stratigraphy, structure and geodynamics provided an VESPE F. (2002) - Geophysical interpretation of geodetic deforma-
invaluable source of inspiration for many geologists working in the tions in the central Mediterranean area. In: «Plate Boundary Zones»,
Meditarranean area. S. Stein & J. Freymueller (Eds), Geodynamics Series, 30, 57-65.