Catherine Chauvel, CNRS senior researcher at IPGP, has been awarded a European ERC Advanced Grant for her project SHRED : Survival of Hadean REmnants in a Dynamic mantle.
Plate tectonics drives the formation and destruction of crust and introduces surface material into the deep Earth, while mantle convection mixes materials back together, erasing their diversity. Geochemical heterogeneities in modern volcanics indicate the survival of Hadean (≈ 4.5 Ga) remnants, and their mare existence raises first-order questions: What is the nature of the material carrying the odd geochemical signatures? How can Hadean material survive in an actively convecting mantle? What are the physical properties of material that can be preserved for billions of years, and yet that can be entrained in mantle plumes? Can Hadean remnants be stored in the structures seismically imaged in the lowermost mantle? Answering these questions is the challenging aim of SHRED. I will define the location, dimensions, structure, physical nature and composition of the ‘storage site’ of old material and I will constrain the conditions necessary for the material to be sampled in hotspots.
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