Magnesium isotopic composition of achondrites

Oxygen isotope composition of the primitive Achondrites

Introduction: Primitive achondrites are meteorites with near-chondritic bulk compositions and nonchondritic textures [1]. They are thought to be either highly metamorphosed chondrites, or residues formed by low degrees of partial melting [1]. They thus record the conditions at the onset of asteroidal melting and form an important link between chondrites and the extensively melted achondrites (i...

Magnesium isotopic composition of the Earth and chondrites

To constrain further the Mg isotopic composition of the Earth and chondrites, and investigate the behavior of Mg isotopes during planetary formation and magmatic processes, we report high-precision (±0.06& on dMg and ±0.07& on dMg, 2SD) analyses of Mg isotopes for (1) 47 mid-ocean ridge basalts covering global major ridge segments and spanning a broad range in latitudes, geochemical and radioge...

MAGNESIUM ISOTOPIC COMPOSITION OF CAIs AND CHONDRULES FROM CBb CHONDRITES

M. Gounelle, E. D. Young, A. Shahar and A. Kearsley, Laboratoire d’Étude de la Matière Extraterrestre, Muséum National d’Histoire Naturelle, 57 rue Cuvier, CP52, 75005 Paris, France. Impacts & Astromaterials Research Centre, Department of Mineralogy, The Natural History Museum, London SW7 5BD, UK. ([email protected]). Institute of Geophysics and Planetary Physics, UCLA. Department of Earth and S...

Petrologic and oxygen-isotopic investigations of eucritic and anomalous mafic achondrites

Magnesium Isotopic Compositions of Cm Hibonite Grains

Introduction: Hibonite is thought to be one of the earliest solids in the solar system, occurring as either a condensate or refractory residue, therefore the Mg isotope compositions of hibonite grains can help elucidate the initial abundance and distribution of Al in the early solar system. Previous investigations [1-6] of CM hibonite grains have demonstrated that hibonite shows a bimodal patte...