|Author(s)||Moreira M1, Dosso Laure2, Ondreas Helene3|
|Affiliation(s)||1 : Univ Paris Diderot, Inst Phys Globe, Equipe Geochim & Cosmochim, F-75005 Paris, France.
2 : IFREMER, CNRS, UMR6538, F-29280 Plouzane, France.
3 : CNRS, UMR7154, F-75005 Paris, France.
|Source||Geophysical Research Letters (0094-8276) (American Geophysical Union), 2008-05 , Vol. 35 , N. 10 , P. NIL_49-NIL_54|
|WOS© Times Cited||18|
|Keyword(s)||Pacific Antarctic ridge, mantle geochemistry, helium isotopes|
|Abstract||The first isotopic data and concentrations of helium are reported for the Pacific-Antarctic ridge between 52.5 degrees S and 41.5 degrees S. The He-4/He-3 ratio is extremely homogeneous over more than 1200 km, with a mean ratio of 99,275 (R/Ra = 7.29) and a standard deviation of 2719 (0.19), which is the lowest dispersion observed for the global mid oceanic ridge system. Moreover, the Menard T. F. is a frontier between two mantles with slightly different helium isotopic ratios (96,595 +/- 1520 and 100,347 +/- 2330). No difference in the helium concentration between the two ridge segments defined by the Menard T. F. can be observed, as well as no significant difference in the U and Th contents suggesting that the difference in helium isotopic ratio is old (>500 My) and may represent a slight difference in degassing or/and trace element depletion history.|
Moreira M, Dosso Laure, Ondreas Helene (2008). Helium isotopes on the Pacific-Antarctic ridge (52.5°–41.5°S). Geophysical Research Letters, 35(10), NIL_49-NIL_54. Publisher's official version : https://doi.org/10.1029/2008GL033286 , Open Access version : https://archimer.ifremer.fr/doc/00000/4348/