| A | B |
|---|
| 1906 earthquake | San Francisco |
| 1964 earthquake | Alaska |
| 1923 earthquake | Tokyo |
| 1556 earthquake | Shensi, China |
| 1755 earthquake | Lisbon, Portugal |
| 1995 earthquake | Kobe, Japan |
| Epicentre | surface point directly above the Focus |
| Certain types of soil will liquefy | when shaken |
| Earthquakes on the sea floor | often create a tsunami |
| Aftershocks are | renewed tremors following a major earthquakes |
| Energy of motion | kinetic energy |
| Elastic rebound theory is based on | release of stress |
| The Mercallis scale is based on | intensity |
| Seismographs measure | ground motion |
| Amplitude | height of the waves |
| The greater the mass, the greater the | inertia |
| Earthquake scientists | seismologists |
| Tectonic plate boundaries are marked | by numerous active faults |
| J. Tuzo Wilson | developed theory of plate tectonicsg |
| Geophhysics is a discipline that combines | geology and physics |
| wave speed varies with the | density of the medium |
| 100 km. thick | Atmosphere |
| 11 km. thick | Hydrosphere |
| 20-50 km. thick | Crust |
| 2900 km. thick | Mantle |
| Uppermost mantle | Lithosphere |
| Arrival times of P and S waves | are used to locate the epicentre |
| Two basic kinds of earthquake waves | P waves and S waves |
| Earthquake zones are regions | of active crust at or near plate boundaries |
