| A | B |
|---|
| geology | the scientific study of nature, formation, origin, and development |
| geologic time scale | a scale of geology |
| era | a system of of dating events from one particular event or moment |
| big bang theory | a theory of how the universe was created |
| theory | an organized body of ideas |
| law | a reloshionship between cause and effect |
| pangaea | a giant land mass |
| fossils | the recognizable remains of a plant or animal |
| index fossils | fossils of an organism that lived in many places , but over a short time period |
| trilobite | extinct aquatic arthropods found widly in paleozoic deposits |
| ammonite | a fossil genus of cephalopods, of spiral form and often very large, abundent in the trassic era |
| extinct | died out, no longer found |
