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Comment: 19:53 - 20:30 (00:37)
Source: Annenberg/CPB Resources - Earth Revealed - 6. Plate Dynamics
Keywords: "Don L. Anderson", convection, mantle, core, "Kormel Boundary", viscosity, "magnetic field"
Our transcription: Whether there is boundary layer convection in the mantle or not, there is another kind of convection that occurs in the outer portion of the Earth's core.
Then, as we cross the Kormel Boundary we're into a very low viscosity fluid molten iron core.
This is convecting very, very rapidly and forming the Earth's magnetic field, so basically we have two parts of the Earth that are convecting.
The mantle is a very sluggish high viscosity fluid, more or less like tar that's trying to convect on a hot day.
Whereas, the core itself has more the viscosity of water, and it's convecting very, very rapidly.
So there's two scales of convection and two kinds of convection in the Earth.
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