Thermal conductivity in the mantle

Scientists have studied perovskite, the Earth’s most abundant mineral, under pressures ranging from 20 to 145 GPa. Using X-ray emission spectroscopy, they discovered that this material becomes almost completely transparent above 120 GPa. This would mean that, in the lower mantle, heat from the core can be transferred through the material itself, without the need for large convection movements as previously imagined.

At 120 GPa, the perovskite in the lower mantle is transparent to infrared light and permits transmission of heat from the core to the mantle. 

Further information:

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• Ref.: J. Badro et al., Science 305, 383-386 (2004).