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| Graham, David W.; Hanan, Barry B.; Hemond, Christophe; Blichert-toft, Janne; Albarede, Francis. |
| We report He-3/He-4 for 150 mid-ocean ridge basalt (MORB) glasses from the Southeast Indian Ridge (SEIR). Between 81 degrees E and 101 degrees E He-3/He-4 varies from 7.5 to 10.2 R-A, encompassing more than half the MORB range away from ocean island hot spots. Abrupt transitions are present and in one case the full range occurs over similar to 10 km. Melting of lithologically heterogeneous mantle containing a few percent garnet pyroxenite or eclogite leads to lower He-3/He-4, while He-3/He-4 above similar to 9 R-A likely indicates melting of pyroxenite-free or eclogite-free mantle. Patterns in the length scales of variability represent a description of helium isotopic texture. We utilize four complementary methods of spectral analysis to evaluate this... |
| Tipo: Text |
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| Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00217/32839/31308.pdf |
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