What is one of the two primary energy sources sustaining the heat engine of convection?

Answer

Residual heat from Earth's formation

One primary contributor is the residual heat left over from the Earth's formation approximately 4.5 billion years ago, which continues to be lost from the interior, particularly across the core-mantle boundary.

What is one of the two primary energy sources sustaining the heat engine of convection?

#Videos

Mantle Convection explained by Peter Bunge - YouTube

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