Across
- 4. the amount of time it takes for half of a remaining isotope to decay
- 6. when water mineralizes and turns to stone
- 8. leave a cavity or indent where an organism once was
- 9. a fossil is classified as this when it is widespread, abundant, and was living for a short period of time
- 10. the type of rock that fossils are found in
- 13. the law meaning that rocks found inside of other rocks are the older of the two
Down
- 1. determining the age or rock by using radioactive material to find the half-life
- 2. the law that newer rock layers are on top of old layers
- 3. forms when an organism dies and the space is filled with minerals
- 5. features like faults and dikes are newer than the rock they cut through
- 7. fossil forms when an insect is trapped in amber
- 11. provides indirect evidence of life in the past
- 12. occurs when plants and animals die, leaving a film of carbon behind