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Rare earth distribution and its correlation with clay mineralogy in the clay-sized fraction of Cretaceous and Pliocene sediments (central Portugal)

Published online by Cambridge University Press:  09 July 2018

M. I. Prudêncio
Affiliation:
Departamento de Quimica, ICEN, LNETI, 2685 Sacavém
M. O. Figueiredo
Affiliation:
Centro de Cristalografia e Mineralogia, IICT, Al. Afonso Henriques, 41, 4° E, 1000 Lisboa, Portugal
J. M. P. Cabral
Affiliation:
Departamento de Quimica, ICEN, LNETI, 2685 Sacavém

Abstract

The REE contents in the clay-sized fractions of nineteen Cretaceous and Pliocene continental sediments, Portugal, were found to be correlated with kaolinite. No correlation is apparent between clay mineralogy and La/Lu or Eu/Sm ratios. The Eu anomaly is generally smaller (or even absent) in the clay-sized fraction than in the corresponding whole sediment, probably due to a greater ability of the clay minerals to accommodate Eu (as Eu2+) rather than the other REE released during weathering.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1989

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