Vocabulary Cards 1
a layer of molten iron and nickel that surrounds the inner core of Earth
outer core
the layer of rock that forms Earth’s outer surface
crust
the layer of hot, solid material between Earth’s crust and core
mantle
a dense sphere of solid iron and nickel in the center of Earth
inner core
the amount of force pushing on a surface or area
pressure
a rigid layer made up of the uppermost part of the mantle and the crust
lithosphere
the soft layer of the mantle on which the lithosphere floats
asthenosphere
the amount of mass in a given space; mass per unit volume
density
the movement of energy from a warmer object to a cooler object
heat transfer
the direct transfer of energy through empty space by electromagnetic waves
radiation
the transfer of heat from one substance to another by direct contact of particles of matter
conduction
the transfer of heat by movements of a fluid
convection
the preserved remains or traces of living things
fossil
the undersea mountain chain where new ocean floor is produced; a divergent plate boundary
mid-ocean ridge
a system that determines the distance of an object under water by recording echoes of sound waves; gets its name from sound navigation and ranging
sonar
the hypothesis that the continents slowly move across Earth’s surface
continental drift
a vibration that travels through Earth carrying the energy released during an earthquake
seismic wave
the movement of a fluid, caused by differences in temperature, that transfers heat from one part of the fluid to another
convection current
the process by which molten material adds new oceanic crust to the ocean floor
sea-floor spreading
the name of the single landmass that broke apart 225 million years ago and gave rise to today’s continents
Pangaea