Plate Tectonics

the theory that continents were once connected but have drifted apart.

mineralized remains of organisms showing how long-dead organisms lived and how their bodies were structured.

fossil that is widespread, lived over a relatively short period of time and can be used to correlate rock strata.

the theory that the crust is divided into pieces called tectonic plates that slowly move on top of the mantle.

huge pieces of crust that slowly move on the upper ductile part of the mantle

the thin, solid outermost layer of Earth; made of less dense silicates and is either continental (landmasses) or oceanic (ocean floors)

the layer of molten material under the crust

relating to the whole world

the rigid outer layer of Earth that contains the crust and mantle

Earthquakes, volcanoes, etc.

melted; liquified

the process by which hot material rises and cooler material sinks

the condition of a solid that allows it to flow like plastic putty

the boundary between two tectonic plates moving away from each other; if on land, it creates rift valleys; if on seafloor, it creates new ocean crust and mountainous regions

melted or molten rock material beneath Earth's surface; cools slowly to form rocks with larger crystals