摘要：60 Fe- 60 Ni systematics in quenched angrites and two old eucrites were investigated by secondary ion mass spectrometry. The 60 Ni/ 62 Ni isotopic compositions were normal within 2σ errors. The inferred initial 60 Fe/ 56 Fe ratios for quenched angrites was (6±9)× 10 −9 , and similar upper limit values were also obtained from eucrites. Using the age difference of approximately 5 Ma between the quenched angrites and Ca−Al-rich inclusions, the initial 60 Fe/ 56 Fe ratio at the start of the solar system was calculated to be approximately (6±9)× 10 −8 . This initial ratio is significantly smaller than previously published values obtained from chondritic materials, suggesting the heterogeneous distribution of 60 Fe in the solar nebula.
