Vibrations that travel through Earth carrying the energy released during an earthquake.
The force exerted on a surface divided by the total area over which the force is exerted.
The layer of rock that forms Earth's outer surface.
A dark, dense, igneous rock with a fine texture, found in oceanic crust.
A usually light-colored igneous rock that is found in continental crust.
The layer of hot, solid material between Earth's crust and core.
A rigid layer made up of the uppermost part of the mantle and the crust.
The soft layer of the mantle on which the lithoshpere floats.
A layer of molten iron and nickel that surrounds the inner core of Earth.
A dense sphere of solid iron and nickel at the center of Earth.
The direct transfer of energy through space by electromagnetic waves.
The direct transfer of thermal energy from one substance that it is touching.
The transfer of thermal energy by the movement of fluid.
The amount of mass of a substance in given volume; mass per unit volume.
The movement of a fluid, caused by differences in temperature, that transfers heat from one part of the fluid to another.
The hypothesis 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.
A trace of an ancient organism that has been preserved in rock.
An undersea mountain chain where new ocean foo is produced.
A device that determines the distance of an object under water by recording echoes of sound waves.
The process by which molten material adds new oceanic crust to the ocean floor.
A deep valley along the ocean floor beneath which oceanic crust slowly sinks toward the mantle.
The process by which oceanic cus sinks beneath a deep-ocean trench and back into the mantle at a converent plate boundary.
A section of the lithosphere that slowly moves over the asthenosphere, carrying pieces of continental and oceanic crust.
A well-tested concept that explains a wide range of observations.
The theory that pieces of Earth's lithosphere are in constant motion, driven by convection currents in the mantle.
A break or crack in Earth's lithosphere along which the rocks move.
A plate boundary where two plates move away from each other.
A deep valley that forms where two plates move apart.
A plate boundary where two plates move toward each other.
A plate boundary where two plates move past each other in opposite directions.
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