LGSR - Laboratoire GéoSciences Réunion

Le Laboratoire GéoSciences Réunion fait partie de l'équipe Géologie des systèmes volcaniques au sein de l'unité mixte de recherche UMR CNRS 7154 –IPGP dont la tutelle principale est l'Institut de Physique du Globe de Paris.

Les tutelles secondaires sont :

• Université de La Réunion
• Université Paris 7

Combined analysis of whole rocks, melt inclusions and matrix glasses of Piton de la Fournaise products unravel three stages of magmatic differentiation. The deepest (> 7.5 km depth) is dominated by clinopyroxene crystallization (Line 1). Above (2.5 km), fractionation is dominated by olivine, yielding steady state basalts at the top of the chamber and picrites at its bottom (Line 2). In shallow cooling dykes and subsurface pockets of magma, melts become more differentiated by clinopyroxene+plagioclase fractionation (Line 3). The shift from one differentiation line to the next is pressure dependent (Famin et al., 2009).