Timescales of Planetesimal Differentiation in the Early Solar System

摘要: __________________________________________________________________ Chronological constraints on the formation times of a variety meteoritic materials indicate that planetesimal differentiation occurred rapidly in early solar system. Some planetesimals only experienced earliest stage onset melting and were subsequently arrested state. On some these bodies, such incipient began within ~2 to 5 Myr calcium-aluminum-rich inclusions (CAI), but possibly extended ≥10 others. Extensive took place yet other form silicate crust-mantle reservoirs metallic cores. Crust ~4 CAI formation, likely at least ~10 Myr. Global mantle differentiation, which established source crustal materials, contemporaneously for angrites eucrites, ~3 4 formation. Metal segregation different narrow time interval ≤5 Myr; specific case Howardite-Eucrite-Diogenite (HED) parent body, process core is estimated have ~0.6 before global differentiation. Following metal segregation, crystallization over 10 or more.