Descrizione del progetto
L’origine volatile della Terra svelata tramite analisi degli isotopi di krypton e xenon
Non si sa molto in merito alla composizione dei gas nobili pesanti krypton (Kr) e xenon (Xe) nel mantello terrestre, e per questo motivo la storia volatile della Terra rimane per lo più sconosciuta. Il progetto VolatileOrigin, finanziato dall’UE, misurerà con precisione gli isotopi di Kr e Xe presenti nei campioni ricavati dal mantello, tra cui basalti e diamanti della dorsale medio-oceanica, e in diversi tipi di meteoriti. Grazie alla definizione delle composizioni dei campioni della dorsale medio-oceanica e dei diamanti, i ricercatori saranno in grado di caratterizzare la portata delle eterogeneità di Kr e Xe del mantello, introdotte tramite il riciclaggio progressivo dei gas atmosferici nobili mediante subduzione, riuscendo così a rilevare le fonti di questi volatili nel mantello. Masse di dati precisi sui meteoriti relativi agli isotopi di Kr e Xe non radiogeni approfondiranno la comprensione delle composizioni misurate del mantello e sveleranno le impronte digitali delle fonti volatili.
Obiettivo
The presence of volatile elements such as carbon, nitrogen, water, noble gases, on terrestrial planets is a requirement for planet habitability, yet their origin is still highly debated. Noble gases are invaluable tracers of volatile sources due to their inertness, in particular their non-radiogenic isotopes have kept remnant signatures of planetary accretion. Krypton and xenon are mighty tools to distinguish between chondritic and solar volatile sources due to the distinct isotopic compositions of these end-members. However, the heavy noble gas (Kr, Xe) compositions of the Earth’s mantle is poorly determined. Hence, the Earth’s mantle volatile history remains largely unknown. The objectives of this project are to precisely measure the non-radiogenic Kr and Xe isotopes in mantle-derived samples, including mid-ocean ridge basalts and diamonds, and in meteorites of different types in order to better understand Earth’s volatile origin. Determining the compositions of mid-ocean ridge and diamond samples will allow to characterize the extent of mantle Kr and Xe heterogeneities, introduced through progressive atmospheric noble gas recycling via subduction, and, hence to identify the source(s) of these volatiles in the mantle. Precise bulk meteorite data for the non-radiogenic Kr and Xe isotopes are incomplete and will be crucial in our understanding of the measured mantle compositions to fingerprint the volatile sources. This project will use a novel protocol for the specific measurements of these isotopes in mantle-derived samples associated with noble gas mass spectrometry. The MSCA fellowship represents a unique opportunity for me to learn new analytical skills in cosmochemistry, to improve my soft skills and to secure my fruitful reintegration in Europe. I will transfer to the host lab my expertise of mantle geochemistry. On the whole, this project will strengthen my scientific independence, taking me closer to achieve an outstanding academic position in Europe.
Campo scientifico
- natural scienceschemical sciencesinorganic chemistrynoble gases
- natural sciencesphysical sciencesastronomyplanetary sciencesmeteorites
- natural sciencesphysical sciencesastronomyplanetary sciencesplanets
- natural sciencesearth and related environmental sciencesgeochemistrycosmochemistry
- natural scienceschemical sciencesanalytical chemistrymass spectrometry
Parole chiave
Programma(i)
Argomento(i)
Meccanismo di finanziamento
MSCA-IF - Marie Skłodowska-Curie Individual Fellowships (IF)Coordinatore
8092 Zuerich
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