Mardi 24 Novembre à 14h : Marion Garçon (post-doc LMV)
Titre : “Erosion de la croute Archéenne et recyclage dans le manteau Terrestre”
Title: “Archean crust erosion and recycling into the Earth’s Mantle”
Archean sedimentary rocks have amalgamated the erosion products of large continental areas, hence offer a comprehensive view of the composition of Archean continents that is not available from the igneous rock record. Through time, most of these sediments have been recycled into the Earth’s mantle at subduction zone. Today, only a few witnesses are preserved at surface of the Earth. Here we explore trace and major element data as well as radiogenic isotope systematics (Sm-Nd, Lu-Hf) of Archean sedimentary rocks drilled in the Barberton Greenstone belt, South Africa to provide new constrains on the composition of the Archean crust and to investigate the effects of sediment recycling on the composition of the mantle through time.