Data/hora: 27/07/2024 03:11:42

Provedor de dados: 	Institutional Archive of Ifreme (ArchiMer)	
País: 	France	
Título: 	Geochemistry of the mantle beneath the Rodriguez Triple Junction and the South-East Indian Ridge	
Autores: 	Michard, A; Montigny, R; Schlich, R.	
Data: 	1990	
Ano: 	1990	
Resumo: 	Rare earth element abundances and Sr, Nd, Pb isotope compositions have been measured on zero-age dredge sample from the Rodriguez Triple Junction (RTJ) and the South-East Indian Ridge (SEIR). Along the SEIR, the geochemical "halo" of the St. Paul hot spot has a half-width of plus or minus 400 km and the data may be fairly well accounted for by a binary mixing between an Indian MORB-type component ( super(87)Sr/ super(86)Sr = 0.7028, super(143)Nd/ super(144)Nd = 0.51304, super(206)Pb/ super(204)Pb = 17.8) and the plume-type St. Paul component (0.7036, 0.5129, and 18.7 respectively). The RTJ has distinctive geochemical properties which contrast with those of the adjacent ridge segments. Low super(206)Pb/ super(204)Pb ratios which plot to the left of the geochron, rather high super(208)Pb/ super(204)Pb and super(87)Sr/ super(86)Sr ratios (17.4, 37.4, and 0.7031 respectively), a striking isotopic homogeneity, and variable LREE/HREE fractionation with (La/Sm) sub(N) = 0.3-0.8 make this triple junction an anomalous site. The geochemical properties of the Indian Ocean basalts have been examined using a three-component mantle model.	
Tipo: 	Text	
Idioma: 	Inglês	
Identificador: 	http://archimer.ifremer.fr/doc/00268/37944/36025.pdf

http://archimer.ifremer.fr/doc/00268/37944/	
Editor: 	Gauthier-Villars	
Formato: 	application/pdf	
Fonte: 	Oceanologica Acta, Special issue (0399-1784) (Gauthier-Villars), 1990	
Fonte: 	info:eu-repo/semantics/openAccess

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