Thermal evolution of the Martian core: Implications for an early dynamo

  title={Thermal evolution of the Martian core: Implications for an early dynamo},
  author={Jean‐Pierre Williams and Francis Nimmo},
Mars is thought to have possessed a dynamo that ceased ;0.5 b.y. after the formation of the planet. A possible, but ad hoc, explanation is an early episode of plate tectonics, which drove core convection by rapid cooling of the mantle. We present an alternative explanation: that the Martian core was initially hotter than the mantle after core formation, providing an initial high heat flux out of the core. A core initially 150 K hotter than the mantle can explain the early dynamo without… 

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