Temperatures of mantle sources of mid-ocean ridge basalts, ocean island basalts and Archean komatiites
Laboratoire(s)/équipe(s) du LabEx OSUG impliqué(e.s) : ISTerre
Porteur du Projet : Alexander Sobolev
Our project aims to determine the consequences of thermal heterogeneity of the convecting mantle and to understand the role of hot mantle plumes in the sources of ocean island basalts, mid-ocean ridge basalts and Archean komatiites. We will use olivine-spinel Al partitioning to determine source temperatures in order to resolve long-standing issues concerning the temperatures of plumes and komatiites, and by inference the very existence of thermo-chemical mantle plumes. We will study olivine phenocrysts and their spinel inclusions in primitive samples of mid-ocean ridge basalts (for different spreading rates), ocean island basalts (Hawaii, Reunion, Iceland, Gorgona, Canaries, Polynesia) and Archean komatiites (S. Africa, Australia, Canada) available in ISTerre. As a major analytical tool we will use the cutting-edge electron microprobe of ISTerre and newly developed high-precision analytical protocols for olivine analysis.
Soutien attribué : 10 900 € en 2014