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Science
Chap. 4 note cards
Term | Definition |
---|---|
Fossils | Traces or remains of living things from long ago |
Original remains | Fossils that are the actual bodies or body parts of organisms |
Ice core | A tubular sample that shows the layers of snow and ice that built up over thousands of years |
Relative age | Is the age of an event or object in relation to other events or objects |
Index fossils | Fossils of organisms that were common, that lived in many areas, and that existed only during specific spans |
absolute age | The actual age of an event or object |
half-life | The length of time it takes half of the atoms in a sample of a radioactive element to change from an unstable form into another form |
uniformitarianism | Huttons theory or that the earth is an always-changing place |
Geologic time scale | divides the earths history into intervals of time defined by major events or changes on earth |