The thermal transport properties of minerals at high temperature and high pressure are important for understanding the internal evolution and dynamic processes of the Earth. Here, we carry out a detailed study on the lattice thermal conductivities (\({\kappa }_\text {latt}\)) of \(\text {Mg}_2\text {SiO}_4\) under upper mantle and transition zone conditions by anharmonic lattice dynamics method. The calculations show that the \({\kappa }_\text {latt}\) of \(\text {Mg}_2\text {SiO}_4\) increase with the phase transitions, which agree with the previous measurements and are attributed to the increase of lifetime and group velocity under extreme conditions. The \({\kappa }_\text {latt}\) of \(\text {Mg}_2\text {SiO}_4\) along the geotherm shows a 64\(\%\) jump at 410 \({\textrm{km}}\) and 71\(\%\) jump at 520 \(\textrm{km}\). The anisotropy in the \({\kappa }_\text {latt}\) of olivine and wadsleyite decreases with increasing pressure. The present findings offer a fundamental knowledge of the \({\kappa }_\text {latt}\) of \(\text {Mg}_2\text {SiO}_4\) under extreme conditions, which are crucially important for understanding the thermal transport processes in the Earth.

矿物在高温高压下的热传输特性对于理解地球内部演化和动力过程具有重要意义。在这里，我们对上地幔下\(\text {Mg}_2\text {SiO}_4\)的晶格热导率 ( \({\kappa }_\text {latt}\) )和通过非调和晶格动力学方法的过渡区条件。计算表明，\(\text {Mg}_2\text {SiO}_4\)的\({\kappa }_\text {latt}\)随着相变而增加，这与之前的测量一致并且是归因于极端条件下寿命和群速度的增加。\ ({\kappa }_\text {latt}\)的\(\text {Mg}_2\text {SiO}_4\)沿地热显示 64 \(\%\)在 410 \({\textrm{km}}\)和 71 \(\%\)处跳跃跳到 520 \(\textrm{km}\)。橄榄石和瓦兹利石的\({\kappa }_\text {latt}\) 的各向异性随着压力的增加而降低。目前的研究结果提供了极端条件下\(\text {Mg}_2\text {SiO}_4\) 的 \( { \kappa }_\text {latt}\)的基本知识，这对于理解至关重要地球上的热传输过程。