The Thermal State of Earth's Core

Earth9s core consists of a molten outer layer surrounding a solid inner core, but models suggest that earlier in Earth9s history, the core was completely molten. In his Perspective, Buffett discusses the current knowledge of heat flows at the core-mantle boundary, which drive Earth9s magnetic field. Today9s heat flows are reasonably well understood, but the thermal history of Earth9s core remains unclear. To determine when Earth9s core solidified, better knowledge of the partitioning of radiogenic elements and more reliable estimates of the power requirements for Earth9s magnetic field are required.