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Chinese Journal of Geochemistry

, Volume 24, Issue 1, pp 9–17 | Cite as

Geochemistry of Late Cretaceous (60–67 Ma) igneous activities in the hebrides terrace seamount (guyot) area, Scotland

  • M. El-Tokhi
  • M. Omran
  • A. El-Muslem
Article

Abstract

Tholeiitic basalts in various stages of alteration were dredged from Late Cretaceous volcanic rocks (60–67 Ma) in the Hebrides Terrace seamount area in the Atlantic Ocean. These rocks are extrusive olivine basalts, including high- and low-Al basalts. High-Al basalts are depleted in MgO, CaO, Cr, Sc, V, Sr, Zr and enriched in TiO2, Na2O, Nb, Rb as compared with low-Al basalts. Petrography and bulk-rock composition (major, trace and rare-earth elements) data defined clear tholeiitic suites displaying possible liquid lines of descent related to different degrees of crystal fractionation and partial melting. Isotopic dating of dredged samples gave the guyot an age of 60–67 Ma, in support of the assumption that it was formed during the Late Cretaceous.

Key words

silicate analysis standard sample rock and mineral 

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Copyright information

© Science Press 2005

Authors and Affiliations

  • M. El-Tokhi
    • 1
  • M. Omran
    • 1
  • A. El-Muslem
    • 2
  1. 1.Geology Dept.Mansoura UniversityDamiettaEgypt
  2. 2.Geology Dept.United Arab Emirates UniversityUnited Arab Emirates

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