title: Mechanisms of magma generation beneath hawaii and mid-ocean ridges: uranium/thorium and samarium/neodymium isotopic evidence.
abstract: Measurements of uranium/thorium and samarium/neodymium isotopes and concentrations in a suite of Hawaiian basalts show that uranium/thorium fractionation varies systematically with samarium/neodymium fractionation and major-element composition; these correlations can be understood in terms of simple batch melting models with a garnet-bearing peridotite magma source and melt fractions of 0.25 to 6.5 percent. Midocean ridge basalts shows a systematic but much different relation between uranium/thorium fractionation and samarium/neodymium fractionation, which, although broadly consistent with melting of a garnet-bearing peridotite source, requires a more complex melting model.
authors.forename: K W
authors.initials: KW
authors.lastname: Sims
authors.forename: D J
authors.initials: DJ
authors.lastname: Depaolo
authors.forename: M T
authors.initials: MT
authors.lastname: Murrell
authors.forename: W S
authors.initials: WS
authors.lastname: Baldridge
authors.forename: S J
authors.initials: SJ
authors.lastname: Goldstein
authors.forename: D A
authors.initials: DA
authors.lastname: Clague