A break or crack in Earth's lithosphere along which the rocks move.

The soft layer of the mantle on which the lithosphere floats.

The transfer of thermal energy by the movement of a fluid.

A layer of molten iron and nickel that surrounds the inner core of Earth.

The direct transfer of energy through space by electromagnetic waves.

The direct transfer of thermal energy from one substance to another substance that it is touching.

A plate boundary where two plates move past each other in opposite directions.

The movement of a fluid, caused by differences in temperature, that transfers heat from one part of the fluid to another.

The hypothesis that states that the continents slowly move across Earth's surface.

The name of the single landmass that broke apart 200 million years ago and gave rise to today's continents.

The process by which molten material adds new oceanic crust to the ocean floor.

A section of the lithosphere that slowly moves over the asthenosphere, carrying pieces of continental and oceanic crust.

A device that determines the distance of an object underwater by recording echoes of sound waves.

The process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent plate boundary.

The force exerted on a surface divided by the total area over which the force is exerted.

A deep valley that forms where two plates move apart.

An undersea mountain chain where new ocean floor is produced.

The layer of rock that forms Earth's outer surface.

A plate boundary where two plates move toward each other.

A rigid layer made up of the uppermost part of the mantle and the crust.

The theory that pieces of Earth's lithosphere are in constant motion, driven by convection currents in the mantle.

A deep valley along the ocean floor beneath which oceanic crust slowly sinks toward the mantle.

A dense sphere of solid iron and nickel at the center of Earth

The layer of hot, solid material between Earth's crust and core.