Across
- 3. Tectonics A scientific theory that describes large scale movement of Earth’s lithosphere.
- 6. The study of ancient life.
- 9. Dating A technique used to date materials such as rocks or carbon, usually based on a comparison between the observed abundance of a naturally occurring radioactive isotope and its decay products.Using known decay rates.
- 11. fossils Fossils used to identify or define geological periods.
Down
- 1. A long and distinct period of history with a particular feature or characteristic.
- 2. A certain amount of time
- 4. The end of an organism or group of organisms,normally species.
- 5. Time Scale The geologic time scale is a system of chronological measurement that relates stratigraphy to time, and is used by geologists, paleontologists, and other earth scientists to describe the timing and relationships between events that have occured throughout Earth’s history.
- 6. Is a group of researchers who study of prehistoric life.
- 7. Is the amount of time required for a quantity to fall to half its value as measured at the beginning of the time period.
- 8. Extinct Reptiles.
- 10. Dating The science of determining the relative order of past events, without necessarily determining their absolute age.
- 12. The planet we live on.