Enstatite chondrites have been regarded as major building blocks of the Earth and other differentiated inner planetary bodies due to the similarity of Δ¹⁷O (deviation of the δ ¹⁷O value from the terrestrial silicate fractionation line) and nucleosynthetic isotope anomalies. However, this hypothesis has been rebutted by the fact that the Earth and enstatite chondrites show distinct Si isotopic compositions. It has been debated whether the origin of this Si isotope difference is the result of nebular or planetary processes. Here we show that the δ ³⁰Si (deviation of ³⁰Si/²⁸Si relative to NBS 28 standard) and the Δ¹⁷O values of chondrules in unequilibrated enstatite chondrites are between −0.20‰ and −0.54‰ and −0.36‰ and +0.26‰, respectively. Furthermore, the chondrules with higher Δ¹⁷O values tend to have lower δ ³⁰Si. The data exhibit values consistent with most of the noncarbonaceous group differentiated planetary bodies. This consistency suggests that the Si and O isotopic compositions of enstatite chondrules record those of the major precursors that formed the differentiated planetary bodies in the inner solar system. Model calculations based on the results reveal that the Si and O isotope variations of the enstatite chondrite chondrules were generated by an interaction between the evaporation-driven SiO-rich gas and partially or fully melted forsterite-rich precursor chondrules. The Mg/Si of the evaporated dust-gas mixtures increased with increasing silicate/metal ratio in the evaporated dust, which may have increased the bulk Mg/Si and δ ³⁰Si value of the inner planetary bodies.

由于 Δ ¹⁷ O（δ ¹⁷ O 值与陆地硅酸盐分馏线的偏差）和核合成同位素异常的相似性，顽火球粒陨石被认为是地球和其他分化的内行星体的主要组成部分。然而，这一假设已被地球和顽火球粒陨石显示出不同的 Si 同位素组成这一事实所驳斥。这种 Si 同位素差异的起源是星云过程还是行星过程的结果一直存在争议。在这里，我们表明δ ³⁰ Si（³⁰ Si/ ²⁸ Si 相对于 NBS 28 标准的偏差）和 Δ ¹⁷未平衡顽火辉石球粒中球粒的 O 值分别在-0.20‰和-0.54‰以及-0.36‰和+0.26‰之间。此外，具有较高 Δ ¹⁷ O 值的球粒往往具有较低的δ ³⁰西。数据显示的值与大多数非碳类分化的行星体一致。这种一致性表明顽火辉石球粒的 Si 和 O 同位素组成记录了内部太阳系中形成差异化行星体的主要前体的组成。基于结果的模型计算表明，顽火石球粒陨石球粒的 Si 和 O 同位素变化是由蒸发驱动的富 SiO 气体与部分或完全熔化的富镁橄榄石前体球粒之间的相互作用产生的。蒸发尘埃-气体混合物的Mg/Si随着蒸发尘埃中硅酸盐/金属比的增加而增加，这可能增加了内部行星体的体积Mg/Si和δ ³⁰ Si值。