Paleomagnetic analyses have suggested that the lunar magnetic field underwent a significant change from 4.25 to 3.19 Ga, indicating the rapid transition of the lunar dynamo mechanism. We used the van der Pauw (vdP) method to measure the electrical resistivity of Fe-S-P alloys under conditions relevant to the lunar core and estimated the thermal conductivity of the Fe-S-P lunar core. These values were incorporated into thermal and dynamo models to investigate the evolution of the lunar core. Our model indicates that the inner core began to grow as early as 4.35 Ga, the solidification regime switched at 3.50 Ga, and the thermal dynamo ceased between 3.78 and 3.51 Ga. The cessation of the dynamo could be due to a low buoyancy flux and insufficient entropy dissipation. Thermal and compositional dynamos cannot sustain the ancient strength of the Moon's magnetic field, and require other energy sources.

中文翻译：

---

基于 Fe-S-P 合金输运特性的月核热演化和发电机演化


古地磁分析表明，月球磁场经历了从 4.25 Ga 到 3.19 Ga 的显着变化，表明月球发电机机制的快速转变。我们使用范德堡（vdP）方法测量了月核相关条件下Fe-S-P合金的电阻率，并估算了Fe-S-P月核的热导率。这些值被纳入热模型和发电机模型中，以研究月球核心的演化。我们的模型表明，内核早在 4.35 Ga 时就开始生长，凝固状态在 3.50 Ga 时切换，热发电机在 3.78 至 3.51 Ga 之间停止。发电机的停止可能是由于浮力通量低和浮力不足造成的。熵耗散。热发电机和合成发电机无法维持月球磁场的古老强度，需要其他能源。