Systematic variation of Sr-, Nd- and Pb- isotopes with time in lavas of Mauritius, Réunion Hotspot

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doi: 10.1093/petrology/egh085
Author(s): Nohda, Susumu; Kaneoka, Ichiro; Hanyu, Takeshi; Xu, Sheng; Uto, Kozo
Author Affiliation(s): Primary:
Kumamoto University, Department of Environmental Sciences, Kumamoto, Japan
University of Tokyo, Japan
Institute of Geoscience, Japan
Volume Title: Journal of Petrology
Source: Journal of Petrology, 46(3), p.505-522. Publisher: Oxford University Press, Oxford, United Kingdom. ISSN: 0022-3530 CODEN: JPTGAD
Note: In English. 43 refs.; illus., incl. charts, 3 tables, sketch map
Summary: We report Sr-, Nd- and Pb-isotopic compositions for the lavas of Mauritius, the second youngest volcanic island in the Reunion hotspot. The lavas of the Older Series (7.8-5.5 Ma) have identical isotopic compositions (87Sr/86Sr = 0.70411 to 0.70422, 143Nd/144Nd = 0.512865 to 0.512854, and 206Pb/204Pb = 19.016 to 19.041) to those of Reunion, where the center of volcanic activity is currently located. The lavas of the Intermediate Series (3.5-1.9 Ma) and Younger Series (0.70-0.17 Ma) are shifted to lower Sr-isotopic compositions (0.70364-0.70394, with 143Nd/144Nd = 0.512813 to 0.512948 and 206Pb/204Pb = 18.794 to 18.984). The Intermediate Series lavas have similar trace-element characteristics (e.g. Zr-Nb, Ba-Y) to those of Rodrigues, in both cases requiring the involvement of an enriched mantle-like component in the mantle source. During the volcanic history of Mauritius, the magmas lost the principal isotopic characteristics of the Reunion hotspot with time, and became gradually imprinted with the isotopic signature of a shallower mantle source that produced the Central Indian Ridge basalts.
Year of Publication: 2005
Research Program: ODP Ocean Drilling Program
Key Words: 02 Geochemistry; 05 Petrology, Igneous and Metamorphic; Alkaline earth metals; Basalts; Central Indian Ridge; Geochemistry; Igneous rocks; Indian Ocean; Indian Ocean Islands; Isotope ratios; Isotopes; Lava; Lead; Leg 115; Lithogeochemistry; Mauritius; Metals; Mid-Indian Ridge; Mid-ocean ridge basalts; Nd-144/Nd-143; Neodymium; Ocean Drilling Program; Pb-206/Pb-204; Radioactive isotopes; Rare earths; Reunion Hot Spot; Sr-87/Sr-86; Stable isotopes; Strontium; Trace elements; Variations; Volcanic rocks
Coordinates: S202000 S202000 E0573000 E0573000
Record ID: 2005038766
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