Helium Isotopic Evidence for a Lower Mantle Component in Depleted Archean Komatiite

Richard1, Marty, Chaussidon

  • 1D. Richard, B. Marty, M. Chaussidon, CNRS, Centre de Recherches Petrographiques et Geochimiques, Rue Notre-Dame des Pauvres, B.P. 20, 54501 Vandoeuvre Cedex, and Ecole Nationale Superieure de Geologie, 94 Avenue De Lattre de Tassigny, 54001 Nancy Cedex, France. N. Arndt, Geosciences, Unite Propre de Recherches 4661 CNRS, Universite de Rennes, 35042 Rennes Cedex, France.

Science (New York, N.Y.)
|July 5, 1996
PubMed
Summary

Archean komatiites, volcanic rocks, suggest deep mantle sources. Helium isotope analysis reveals a lower mantle component, challenging previous upper mantle origin theories for these ancient rocks.

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