论文标题
铁 - 硅质合金在地球核心条件下的导热率低，对地球诺摩的影响
Low thermal conductivity of iron-silicon alloys at Earth core conditions with implications for the geodynamo
论文作者
论文摘要
地球芯由具有光元件的铁（Fe）组成，例如硅（SI）。它的热导率严重影响地球的热结构，进化和动力学，因为它控制了在地球历史上维持地球的巨大和组成源的大小。在这里，我们直接测量了固体Fe和Fe-Si合金的热导率，最高为144 GPA和3300K。15AT％Si合成Fe中的Fe中的电导率大大降低了其电导率，在132 GPA和3000 K时，其电导率降低了约2倍和3000K。一个si的外部核心在％Si时，其电导率为20 w m-1 K-1 k-1 k-1 k-1 si的电导率约为20 w m-1 k-1，低于pure pure pure pure pure Truse pure-pure-pure-pure-Termperutation selly peremperutation。这表明在核心掩体边界上的最小热流量比以前预期的要低3 tw，因此操作地geodynamo所需的热能要少。我们的结果对内部核心年龄的关键限制可能超过20亿年。
Earth core is composed of iron (Fe) alloyed with light elements, e.g., silicon (Si). Its thermal conductivity critically affects Earth thermal structure, evolution, and dynamics, as it controls the magnitude of thermal and compositional sources required to sustain a geodynamo over Earth history. Here we directly measured thermal conductivities of solid Fe and Fe-Si alloys up to 144 GPa and 3300 K. 15 at% Si alloyed in Fe substantially reduces its conductivity by about 2 folds at 132 GPa and 3000 K. An outer core with 15 at% Si would have a conductivity of about 20 W m-1 K-1, lower than pure Fe at similar pressure-temperature conditions. This suggests a lower minimum heat flow, around 3 TW, across the core-mantle boundary than previously expected, and thus less thermal energy needed to operate the geodynamo. Our results provide key constraints on inner core age that could be older than two billion-years.
