Earth's Crust
Earth's outermost layer of rock
Sediment
Small, solid fragments of rock and other materials that are carried and deposited by wind, water or ice. Examples would be sand, mud, or gravel.
Sedimentary Rock
Rock formed when chemical reactions cement sediments together, hardening them
Igneous Rock
Rock that forms from molten rock
Metamorphic Rock
Igneous or sedimentary rock that has been changed into a new kind of rock as a result of great pressure and temperature
Plastic Rock
Rock that behaves like something between a liquid and a solid
Earthquake
Vibration of the earth that results either from volcanic activity or rock masses suddenly moving along a fault
Fault
The boundary between two sections of rock that can move relative to one another
Focus
The point where an earthquake begins
Epicenter
The point on the surface of the earth directly above an earthquake's focus