Non-equilibrium degassing and a primordial source for helium in ocean-island volcanism

@article{Gonnermann2007NonequilibriumDA,
  title={Non-equilibrium degassing and a primordial source for helium in ocean-island volcanism},
  author={Helge M. Gonnermann and Sujoy Mukhopadhyay},
  journal={Nature},
  year={2007},
  volume={449},
  pages={1037-1040}
}
Radioactive decay of uranium and thorium produces 4He, whereas 3He in the Earth’s mantle is not produced by radioactive decay and was only incorporated during accretion—that is, it is primordial. 3He/4He ratios in many ocean-island basalts (OIBs) that erupt at hotspot volcanoes, such as Hawaii and Iceland, can be up to sixfold higher than in mid-ocean ridge basalts (MORBs). This is inferred to be the result of outgassing by melt production at mid-ocean ridges in conjunction with radiogenic… CONTINUE READING