Formation and impact histories of the Solar System and planets from chemical and isotopic investigations of planetary materials

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The long-term scope of my research program is to understand the origin of the Solar System and how planets formed and evolved throughout time. Among these key processes, I am particularly interested in understanding what stellar sources of elements contributed to the Solar System, deciphering the timescales and chemical reservoirs for planetary formation and evolution, and the mechanisms responsible for chemical and isotopic changes in irradiated or shocked planetary materials. This cosmic fingerprinting will enable us to build models to identify the building blocks of terrestrial planets and shape scenarios for their early evolution. Another important theme of my research is to understand the consequences of impacts on planetary surfaces such as those of asteroids, the Moon, Mars, and Earth. To achieve these goals, I will study extra-terrestrial materials such as meteorites, samples brought back from Apollo space missions, and rocks and associated ore deposits from selected terrestrial impact craters.The three planned research themes in my program and their key objectives include:1. Origins of the Solar System and planets: with high-precision mass spectrometry, we can detect variations in the relative atomic abundances of elements in planetary materials. It is of major importance to understand the origin of isotopic heterogeneities in the solar System and trace the nuclear sources of elements that contributed to the molecular cloud, understand their mode and timing of incorporation within the solar nebula, and their distribution throughout the protoplanetary disk. Another important aspect of this theme is to monitor the mass-fractionation and irradiation effects by cosmic rays that affect the isotopic compositions of planetary materials and the subsequent interpretation. 2. Chronology and reservoirs of planetary formation: we can decipher a high-resolution chronology of planetary processes such as condensation (from gas to the first solids), accretion (how the planets grew) and differentiation (how they evolve) in the inner Solar System using the high-resolution U-Pb radiogenic isotope dating system in pristine planetary materials. Meteorites are samples from different locations of the protoplanetary disk exposing variable chemical conditions. In particular, Sm-Nd and Lu-Hf compositions of reduced materials will provide new clues for understanding the processes and reservoirs of planetary formation.3. Impacts in the Solar System: there is widespread evidence of scars left by planetary impacts on the surface of terrestrial planets, asteroids, and Solar System satellites. In the search for extra-terrestrial life, and of new mineralization, it is important to characterize the source and volume of delivered materials, how impact affected planetary surfaces, and understand the distribution through time of these events and the production of ore deposits in some cases. We can develop new models to explain the delivery of materials to the inner and outer Solar System with a better comparative chronology and inter-disciplinary approach of shocked planetary materials.Answering the fundamental questions about the origin of the Solar System and conditions for life to develop in our planetary system is of major interest for humans to understand our environment, the chemical and physical conditions to build habitable planets, and to shape the future of space exploration. The proposed research will be carried out in collaboration with other faculty members at Western and with laboratories across Canada will create a comprehensive environment for training high-qualified students in state-of-the-art facilities dedicated to excellence in geochemical research.