Origin of continental components in Indian Ocean basalts: Evidence from Elan Bank (Kerguelen Plateau ODP Leg 183, Site 1137).
Geology, 29, 2, 147-150, Feb. 2001.
ABSTRACT
Basalts forming the floor of the Indian Ocean are geochemically
distinct from those of the Atlantic and Pacific Oceans. These
differences have been attributed to a deeply recycled continental
component or to widespread dispersion of plume-type mantle within
the Indian Ocean asthenosphere. The discovery of Proterozoic continental
crustal rocks within the uppermost basaltic basement of Elan Bank,
part of the Kerguelen Plateau, shows instead that direct shallow-level
contamination of basaltic magmas by isolated continental crust
fragments may have produced the anomalous isotopic ratios of some
Indian Ocean basalts.
Keywords: Indian Ocean, Kerguelen plume, continental contamination, large igneous province, Kerguelen Plateau.