Question

Study the image about convection currents.

convection currents. A trench is labeled on each side of the lithosphere. Points 1 to 4 are labeled. 1: Mantle. 2: Ridge. 3: Asthenosphere. 4: Outer core.

At which location does heat transfer begin as dense material heats up?

1
2
3
4

Answer 1

4

Heat from the hot outer core warms the base of the mantle/asthenosphere. That heating makes dense mantle material less dense so it rises, driving convection currents.