click below
click below
Normal Size Small Size show me how
CM3 FK1
Earthquakes and Volcanoes
| Term | Definition |
|---|---|
| crust | Earth's outer layer; includes the rock of the ocean floor and large areas of land |
| mantle | the thickest layer of Earth; found just below the crust |
| core | the dense center of Earth; a ball made mostly of two metals, iron and nickel |
| plate | continent-sized slabs of Earth's upper crust and mantle |
| earthquake | a vibration, or shaking, of Earth's crust |
| fault | a break in Earth's crust along which rocks move |
| focus | the point underground where the movement of an earthquake first took place |
| epicentcer | the point on the surface of Earth that is right above the focus of an earthquake |
| seismograph | an instrument that records earthquake waves |
| volcano | a mountain that forms when red-hot melted rock flows through a crack in Earth's surface |
| magma | melted rock inside the Earth |
| lava | a melted rock that reaches Earth's surface |
| vent | the rocky tube in a volcano through which magma rises toward the surface |
| crater | a large basin formed at the top of a volcano when it falls in on itself |