| A | B |
|---|
| volcano | ven in the Earth's surface that often forms a mountain |
| dormant | means "inactive" |
| Mt. Saint Helens | the volcano in Washington state that erupted violently in May 1980 |
| Mt. Pinatubo | the eruption of the century; June 1991 |
| Mt. Unzen | volcano in Japan that erupted killing 41 people including scientists |
| volcanologist | a scientist who studies volcanoes |
| Mt. Kilauea | the world's most active volcano |
| vent | an opening in the Earth's surface that allows the magma to flow through |
| lava | the name given to magma when it is on the surface |
| crater | the opening at the top of the vent |
| Ring of Fire | the belt of volcanoes |
| rift | a long, deep underwater crack that forms from place separation |
| hot spots | areas in the mantle that melt through the crust to form volcanoes |
| geothermal energy | thermal energy from the magma bodies inside the Earth that can be used to produce electricity |
| hot dry rock | new technology that involves pumping water into dry rock instead of using magma |
| fissures | cracks in the Earth's interior |
| basaltic magma | contains less silica; very fluid-like |
| granitic magma | very thick; contains lots of silica |
| shield volcano | type of volcano that has broad and gently sloping sides |
| cinder cone volcano | type of volcano that is steep and loosely consolidated |
| composite volcano | type of volcano that varies between violent and quiet eruptions |
| tephra | lava blasted into the air that solidifies and falls back to the Earth as ash, cinders, or bombs |
| batholith | largest intrusive igneous rock bodies |
| dike | vertical crack cutting through rock layers that has been filled with cooled magma |
| sill | a horizontal crack between rock layers that has been filled with cooled magma |
| laccolith | the dome that forms when a sill continues to push up rock layers |
| caldera | the large opening produced after the collapse of a volcano |
| volcanic neck | the solid igneous core of the vent |
