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根据激光探针分析含尖晶石橄榄岩中矿物的氧同位素组成，应用增量法计算矿物对氧同位素分馏曲线，得到正尖晶石－矿物对氧同位素温度高于含尖晶石橄榄岩的相平衡温度，而用反尖晶石－矿物对计算的氧同位素温度则很接近含尖晶石橄榄岩的相平衡温度，较为合理。因此，地幔橄榄岩中镁铝尖晶石的氧同位素组成继承了其母体反尖晶石特征，即与橄榄石、单斜辉石和斜方辉石平衡的是反结构尖晶石，在其发生相变作用变成正结构尖晶石时未发生氧同位素再平衡。对镁铝尖晶石高温下Mg2＋－Al3＋非趋同有序的热力学分析表明，当s＝1／3时是正尖晶石和反结构尖晶石的分界线，相变温度在1550—1782℃之间，与应用反尖晶石结构分馏系数计算的同位素温度结果一致。
According to the laser probe analysis of oxygen isotope composition of minerals in spinel containing peridotite, the mineral oxygen isotope fractionation curve is calculated by incremental method, and the temperature of spinel-mineral oxygen isotope is higher than that of spinel-bearing peridotite Phase equilibrium temperature, whereas the counter-spinel-mineral pair calculated oxygen isotopic temperature is very close to the phase equilibrium temperature of the spinel containing peridotite, more reasonable. Therefore, the oxygen isotopic composition of Mg-Al spinel in the mantle peridotite inherits the characteristics of its parent inverse spinel, that is, anti-structure spinel is balanced with olivine, clinopyroxene and orthopyroxene, Oxygen isotope rebalancing did not occur when the phase transformation became a positive structure spinel. The thermodynamic analysis of Mg2 + -Al3 + non-convergent order at high temperature of Mg-Al spinel shows that when s = 1/3, the boundary between spinel and spinel is the transition temperature between 1550-1782 ℃ , Which is consistent with the isotope temperature calculated using the inverse spinel structure fractionation coefficient.