| A | B |
|---|
| epicenter | The part of Earth’s surface directly above the focus of an earthquake. |
| faults | A fracture in Earth’s crust at risk for displacement or rupture. |
| tectonic plates | The theory stating that the Earth’s outer shell is divided into about 30 tectonic plates that move slowly in relation to one another. |
| Richter Scale | A scale for expressing the magnitude of an earthquake. |
| Seismic | Of or relating to an earthquake |
| Waves | The way the force of an earthquake moves outward from the epicenter. |
| Retrofit | To furnish a man-made object with new parts or equipment for improved performance. |
| Substrate | An underlying support or foundation, as for a building. |
