N and H isotopic signatures of angrite melts by in situ analyses (SIMS) of mineral-hosted melt inclusions and interstitial glass in two of the oldest volcanic angrites: D'Orbigny and Sahara 99555
Most primitive melt trapped in Mg-rich Ol in D'Orbigny with δD: -348±53 ~ -118±31‰ (standard: SMOW) and δ15N: 0±25 ~ 56±29‰ (standard: atm)，similar to those of CM carbonaceous chondrites, whose parent bodies are thought to have accreted in the outer solar system.
Sahara 99555 show low N and water content (0.020 ± 0.001 ~ 1.25 ± 0.06 wt.%), which possibly indicate that its parental melt underwent a higher degree of degassing compared to D'Orbigny or, alternatively, the two angrites do not sample the same volatile reservoir within the APB.
Given the very old cystallisation age of D'Orbigny, the N and H-rich objests presumably formed beyond the orbit of Jupiter, must have been present in the terrestrial planet-forming region within the first ~4Ma after the formation of CAIs.
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