| A | B |
|---|
| earthquake | a violent shake of the earth's crust |
| focus | the point at which an earthquake occurs under the surface |
| epicentre | the place on the surface of the earth where the earthquake |
| seismic waves | shock waves caused by an earthquake |
| seismograph | an instrument that measures the earthquake waves |
| Richter scale | a scale that measures the force of an earthquake: o = small, 10 = very large |
| volcano | an opening on the earth's crust where ash and lava come out |
| vent | the top of the volcano where the lava and ash come out |
| dormant volcano | sleeping volcano, can still errupt |
| explosive volcano | a violent erruption where large amounts of ash and lava come out of the surface of the earth |
| sheild cone volcano | quiet eruption where lava forms gentle slopes and wide bases |
| cinder cone volcano | made of ash, and rock that are thrown into the air, makes steep slopes and small bases |
| composite cone volcano | alternating ash and lava layers from quiet erruptions to violent erruptions |
