transform boundary

means a plate boundary where 2 plates move past each other in opposite directions


means the process by which oceanic crust sinks beneath a deep ocean trench and back into the mantle at a convergent boundary


means a device that determines the distance of an object under water by recording echoes of sound waves

seismic waves

means vibrations that travel through Earth carrying the energy released during an earthquake

seafloor spreading

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

scientific theory

means a well tested concept that explains a wide range of observations


means the direct transfer of energy through space by electromagnetic waves


means the force exerted on a surface divided by the total area

plate tectonics

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


means a section of the lithospere that slowly moves over the asthenosphere carrying pieces of continenal and ocean crust


means the name of the single landmass that broke apart and gave rise to today's contienents

outer core

means a layer of molten iron and nickel that surrounds the inner core of earth

mid ocean ridge

means an undersea mountain chain where new ocean floor is produced


means the layer of hot solid material between earth's crust and core


means a rigid layer made of the uppermost part of the mantle and the crust

inner core

means a dense sphere of solid iron and nickel at the center of earth


means a light colored igneous rock that is found in continental crust


means a trace of an ancient organism that has been presevred in a rock


means a break or crack in earth's lithosphere along which the rocks move

divergent boundary

means a plate boundary where two plates move away from each other


means the amount of mass of a substance in a given volume; mass per volume

deep ocean trench

means a deep valley along the ocean floor beneath which oceanic crust slowly sinks toward the mantle


means the layer of rock that forms Earth's outer surface

convergent boundary

means a plate boundary where two plates move toward each other

convection current

means the movement of a fluid caused by diferences in temperature, that transfer heat from one part of the fluid to another


means the transfer of thermal energy by the movement of a fluid

continental drift

means the hypothesis that the contienents slowly move across earth's surface


means the direct transfer of thermal energy from one substance to another substance that it is touching


means a dark dense igneous rock with a fine texture found in oceanic crust


means the soft layer of the mantle on which the lithosphere floats

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