What internal process powers the movement of tectonic plates?

What internal process powers the movement of tectonic plates?

• A. Heat from Earth's interior
• B. Solar radiation
• C. Wind
• D. Ocean currents

Answer: (A)

Internal heat in Earth's mantle drives convection, and that convection is what moves the tectonic plates. Heat coming from the planet’s interior creates temperature and density differences in the mantle, causing hotter, less dense material to rise while cooler, denser material sinks. This slow, looping flow sets the stage for the rigid lithospheric plates at the surface to be carried along, with interactions at plate boundaries—like ridges and subduction zones—translating mantle movement into plate motion. Solar energy powers surface weather, wind, and ocean currents, but it doesn’t energize the mantle’s flow or the deep-seated process that moves tectonic plates.

Internal heat in Earth's mantle drives convection, and that convection is what moves the tectonic plates. Heat coming from the planet’s interior creates temperature and density differences in the mantle, causing hotter, less dense material to rise while cooler, denser material sinks. This slow, looping flow sets the stage for the rigid lithospheric plates at the surface to be carried along, with interactions at plate boundaries—like ridges and subduction zones—translating mantle movement into plate motion.

Solar energy powers surface weather, wind, and ocean currents, but it doesn’t energize the mantle’s flow or the deep-seated process that moves tectonic plates.