Postdoctoral Fellow, NASA
Meteorites, cosmochemistry, carbonacious chondrites, hydrothermal alteration, presolar grains, secondary ion mass spectrometry.
B.S., 2011, Earth, Environment and Planetary Sciences, University Paris Diderot (Paris VII)
M.S., 2013, Remote Sensing, University of Paris Diderot (Paris VII) and IPGP
M.S., 2014, Planetology, University of Versailles St-Quentin (UVSQ)
PhD., 2017, Cosmochemistry, Muséum National d'Histoire Naturelle de Paris
Contact & Links
- (202) 478-8463
- Department of Terrestrial Magnetism
Carnegie Institution of Washington
5241 Broad Branch Road, NW
Washington, DC 20015-1305
Chondrites are considered witnesses of the Solar System formation, as they are fragments of undifferentiated asteroids. Even though most of them experienced secondary processes, such as aqueous alteration and thermal metamorphism that altered their pristine mineralogy, they are still a major source of information about the physico-chemical conditions of the protoplanetary disk.
Throughout his Ph.D., Maximilien studied the conditions in which aqueous alteration occurred in the asteroidal parent-bodies of CM carbonaceous chondrites. To do so, he focused on secondary minerals, mainly carbonates, as they are considered a direct snapshot of the chemical and isotopical composition of the fluid which they precipitated from. With collaborators, he noticed that their O-isotopic compositions alone could be used as a tool to determine their temperature of precipitation. This revealed that CM chondrites have a similar thermal history, attesting for a common parent-body origin. Aside from this project, he developed a high-pressure experiment to synthetize standards suitable for the datation of carbonates in meteorites via the radiochronometer 53Mn-53Cr.
Among the diversity of mineral phases constituting chondrites, nanometric to micrometric grains predating the solar system are valuable witnesses of the stellar environment where the solar system formation began. At DTM, Maximilien plans on studying the isotopic and elemental compositions of various families of presolar grains to better constrain their origin and the stellar context that led to their presence in solar system material. The addition of the Hyperion source to the NanoSIMS opens new ways of investigation to improve our understanding of those unusual constituents that remained poorly constrained owing to their small size.