Data/hora: 09/06/2024 08:40:57

Provedor de dados: | Institutional Archive of Ifreme (ArchiMer)
País: | France
Título: | Helium isotopes on the Pacific-Antarctic ridge (52.5°–41.5°S)
Autores: | Moreira, M; Dosso, Laure; Ondreas, Helene.
Data: | 2008-05
Ano: | 2008
Palavras-chave: | Pacific Antarctic ridge; Mantle geochemistry; Helium isotopes.
Resumo: | 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 (&gt;500 My) and may represent a slight difference in degassing or/and trace element depletion history.
Tipo: | Text
Idioma: | Inglês

Identificador:

http://archimer.ifremer.fr/doc/2008/publication-4348.pdf

DOI:10.1029/2008GL033286

Editor: | American Geophysical Union
Relação: | http://archimer.ifremer.fr/doc/00000/4348/
Formato: | application/pdf
Fonte: | Geophysical Research Letters (0094-8276) (American Geophysical Union), 2008-05 , Vol. 35 , N. 10 , P. NIL_49-NIL_54
Fonte: | 2008 American Geophysical Union