Question

• click on this link to read about convection.

1. how does this explanation support how energy from inside the earth might be spreading toward the surface of earth?

this explains that energy would spread toward the surface of the earth with things like volcanoes, sea floor spreading and mountain ridges.

1. how could the concept of convection be used to explain how continents move?

• view the image below to assist with the next few questions.

Explanation:

Convection currents form in Earth's semi-fluid mantle when heat from the core heats lower mantle material, making it less dense and causing it to rise. As this material nears the crust, it cools, becomes denser, and sinks back toward the core. These circular currents exert horizontal force on the tectonic plates (which carry continents) that rest on the mantle. The rising mantle material pushes plates apart at divergent boundaries (like mid-ocean ridges), and sinking material pulls plates together at convergent boundaries, driving the slow movement of continents over millions of years.

Answer:

Convection currents in Earth's mantle drive continental movement:

1. Heat from Earth's core warms lower mantle rock, making it less dense so it rises toward the crust.
2. As the rock cools near the crust, it becomes denser and sinks back toward the core, creating circular convection currents.
3. These flowing currents exert drag on the overlying tectonic plates (which hold continents), pushing them apart at divergent zones (e.g., mid-ocean ridges) and pulling them together at convergent zones, causing the gradual movement of continents over geologic time.