Evolution of helium isotopes in the Earth's mantle

@article{Class2005EvolutionOH,
  title={Evolution of helium isotopes in the Earth's mantle},
  author={Cornelia Class and Steven L. Goldstein},
  journal={Nature},
  year={2005},
  volume={436},
  pages={1107-1112}
}
Degassing of the Earth's mantle through magmatism results in the irreversible loss of helium to space, and high 3He/4He ratios observed in oceanic basalts have been considered the main evidence for a ‘primordial’ undegassed deep mantle reservoir. Here we present a new global data compilation of ocean island basalts, representing upwelling ‘plumes’ from the deep mantle, and show that island groups with the highest primordial signal (high 3He/4He ratios) have striking chemical and isotopic… 
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Temporal evolution of primordial tungsten-182 and 3He/4He signatures in the Iceland mantle plume
Studies of short-lived radiogenic isotope systems and noble gas isotopic compositions of plume-derived rocks suggest the existence of primordial domains in Earth's present-day mantle. Tungsten-182
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