Géochimie isotopique du lithium dans les basaltes-Géochimie des ...

tel-00344949, version 1 - 7 Dec 2008
2. Article soumis à EPSL
and supplementary materials� are satisfactorily explained by a single lower crustal
contaminant.
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Figure 2.9 : A� Variation of Pb isotopic composition of the Chaîne des Puys
series compared to different types of granulites xenoliths exhumed from the
lower crust �Downes et al. 1990, 1991� and to upper crustal hercynian
granitoïds �Downes et al., 1997�. B� zoom on the Pb isotopic variation of the
Chaîne des Puys series.
Several parameters must be assumed, in order to model the evolution of the volcanic
series by the AFC process �DePaolo, 1981�. Bulk distribution coefficients for each element