The oxygen fugacity ($f_{{\text{O}}_2}$) may affect the ionic conductivity of olivine under upper mantle conditions because Mg vacancies can be produced in the crystal structure by the oxidization of iron from Fe²⁺ to Fe³⁺. Here we investigated olivine ionic conductivity at 4 GPa, as a function of temperature, crystallographic orientation, and oxygen fugacity, corresponding to the topmost asthenospheric conditions. The results demonstrate that the ionic conductivity is insensitive to $f_{{\text{O}}_2}$ under relatively reduced conditions ($f_{{\text{O}}_2}$ below Re-ReO₂ buffer), whereas it has a clear $f_{{\text{O}}_2}$-dependence under relatively oxidized conditions ($f_{{\text{O}}_2}$ around the magnetite-hematite buffer). The ionic conduction in olivine may contribute significantly to the conductivity anomaly in the topmost asthenosphere especially at relatively oxidized conditions.

氧逸度（$F_{{\text{哦}}_2}$) 可能会影响上地幔条件下橄榄石的离子电导率，因为通过将铁从 Fe ²⁺氧化为 Fe ³⁺可以在晶体结构中产生 Mg 空位。在这里，我们研究了 4 GPa 下的橄榄石离子电导率，作为温度、晶体取向和氧逸度的函数，对应于最顶层的软流圈条件。结果表明离子电导率对$F_{{\text{哦}}_2}$ 在相对减少的条件下（$F_{{\text{哦}}_2}$低于 Re-ReO ₂缓冲区），而它有一个清晰的$F_{{\text{哦}}_2}$-在相对氧化条件下的依赖性（$F_{{\text{哦}}_2}$在磁铁矿 - 赤铁矿缓冲液周围）。橄榄石中的离子传导可能对最顶部软流圈的电导异常有显着影响，尤其是在相对氧化的条件下。