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Marine Geophysical Researches

, Volume 14, Issue 3, pp 227–248 | Cite as

Southern Segment of the European Geotraverse — a wide-angle seismic refraction experiment in the Sardinia Channel

  • C. Peirce
  • P. J. Barton
Article

Abstract

The Sardinia Channel dataset was collected as part of the European Geotraverse (EGT)—a 4000 km seismic refraction line running from Northern Norway to the Sahara, designed to investigate the structure of the lithosphere beneath Europe. Wideangle seismic data recorded by ocean bottom seismometers deployed in the Sardinia Channel as part of the Southern Segment of the EGT, together with gravity data, were used to constrain the final crustal model. In the centre of the Channel the crust is identified as thinned continental in nature, with a crystalline thickness of 10 km overlain by 4 km of sediments and 2.5 km of water in the most extended region. High velocities in the lower crust in the central region are thought to represent an area of underplating or intrusion by igneous material caused by extension related to the opening of the Tyrrhenian Sea. The crust overlies an anomalously low velocity upper mantle.

Key words

OBS thinned continental crust seismic structure Sardinia Channel rifted continental margin European Geotraverse 

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Copyright information

© Kluwer Academic Publishers 1992

Authors and Affiliations

  • C. Peirce
    • 1
  • P. J. Barton
    • 1
  1. 1.Bullard Laboratories, Department of Earth SciencesUniversity of Cambridge, Madingley RiseCambridgeUK

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