par Lapen, T. J.;Righter, M.;Brandon, A.D;Debaille, Vinciane 
;Beard, B. L.;Shafer, J. T.;Peslier, A. H.
Référence Science, 328, page (347-351)
Publication Publié, 2010
;Beard, B. L.;Shafer, J. T.;Peslier, A. H.Référence Science, 328, page (347-351)
Publication Publié, 2010
Article révisé par les pairs
| Résumé : | Martian meteorite ALH84001 (ALH) is the oldest known igneous rock from Mars and has been used to constrain its early history. Lutetium-hafnium (Lu-Hf) isotope data for ALH indicate an igneous age of 4.091 ± 0.030 billion years, nearly coeval with an interval of heavy bombardment and cessation of the martian core dynamo and magnetic field. The calculated Lu/Hf and Sm/Nd (samarium/neodymium) ratios of the ALH parental magma source indicate that it must have undergone extensive igneous processing associated with the crystallization of a deep magma ocean. This same mantle source region also produced the shergottite magmas (dated 150 to 570 million years ago), possibly indicating uniform igneous processes in Mars for nearly 4 billion years. |
