naturally preserved remains, imprints, or traces of organisms

middle layer of Earth situated between the crust above and the core below

ancient supercontinent, composed of land that forms today's continents

event in which magnetic field reverses direction

mountain range located on the seafloor in the middle of the ocean

conforming to a type, standard, or regular pattern

today's magnetic field; magnets orient themselves to point north

magnetic field in which magnets orient themselves to point south

new ocenaic crust forms at a mid-ocean ridge as old oceanic crust moves away

circulation of material caused by differences in temperature and density

where two plates collide

where two plates separate

cold, rigid outermost rock layer of Earth

capable of being molded of changing shape

theory that Earth's surface is made up of rock plates that move with respect to each other

force created by rising mantle of ocean ridges that creates potential for plates to move away from the ridge

force created by sinking of a plate, or slab, that pulls on the rest of the plate

sinking of a denser plate below a more bouyant plate at a convergent plate boundary

where two plates slide past each other