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pure and applied geophysics

, Volume 119, Issue 6, pp 1134–1143 | Cite as

The crust and upper mantle structure beneath southern Italy by earthquakes and DSS data

  • E. Del Pezzo
  • I. Guerra
  • R. Scarpa
Article

Abstract

This paper describes a travel—time analysis performed for the Italian seismic stations, in particular those operating in southern Italy, in order to study the crust and upper mantle properties in the region. Average P-wave residuals of teleseisms in the distance range 30°–95° with respect to Jeffreys-Bullen tables, at thirteen permanent and temporary stations of southern Italy, are coherent with a high velocity zone beneath Calabria and northern Sicily and low velocity material in the mantle beneath the Eolian Islands. Travel—time residuals from Tyrrhenian intermediate earthquakes show a high velocity structure which extends in a NW direction from a depth of at least 200 km down to 450 km.

A damped least-squares inversion applied to DSS data confirms the existence of low velocity zones in the crust beneath the Eolian Islands, at 8–12 km depth, that agrees with previous results and with the lack of S waves from local earthquakes.

Key words

P-wave residuals Velocity models 

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Copyright information

© Birkhäuser Verlag 1981

Authors and Affiliations

  • E. Del Pezzo
    • 1
  • I. Guerra
    • 2
    • 3
  • R. Scarpa
    • 2
  1. 1.Istituto Internazionale di VulcanologiaCNRCataniaItaly
  2. 2.Osservatorio VesuvianoErcolano, NapoliItaly
  3. 3.Dipartimento di Scienze della TerraUniversità della CalabriaCastiglione Scalo, CosenzaItaly

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