THE DEEP-STRUCTURE OF THE EOLIAN ARC NFILICUDI-PANAREA-VULCANO SECTOR) IN LIGHT OF GRAVITY, MAGNETIC AND VOLCANOLOGICAL DATA

The magnetic and gravimetric methods of investigation have been applie d to the central sector of the Eolian arc, combined with geovolcanolog ical data, for the purpose of defining the structural framework in whi ch the volcanism developed. The processing of the magnetic and gravime tric data involved 3D modeling of the volcanic bodies and the applicat ion of a ''depth separation filter'', in order to subtract from the me asured field the effect caused by the subaerial and submarine volcanic edifices and by all surface inhomogeneities. Magnetic and gravimetric 2.5D modeling on selected profiles has also been done, in a joint int erpretation of the magnetic and gravimetric data, constrained by volca nological knowledge. The interpretation of the final maps and profiles has demonstrated the existence of extensional tectonics, resulting in the development of horst and graben. Volcanism occurs in the graben a reas. In particular, the Salina-Lipari-Vulcano magmatic axis has devel oped in a very deep articulated graben of lithospheric importance and completely filled by volcanic deposits and intrusive bodies. The origi n of this structure and of the associated igneous activity is suggeste d to be related to trans-tensional tectonics along a Plio-Pleistocene regional strike-slip fault system.