Across
- 4. the age of rocks and geologic features compared with other nearby rocks and features
- 7. the numerical age, in years, of a rock or object
- 9. a piece of an older rock that becomes a part of a new rock
- 10. principle that sediments are deposited in large, continuous sheets in all lateral directions
- 11. surfaces where rock has eroded away, producing a break, or gap, in the rock record
- 13. a chart that divides Earth’s history into different time units based on changes in the rocks and fossils
- 14. a method used by geologists to fill in the missing gaps in an area’s rock record by matching rocks and fossils from separate locations
- 15. principle that most rock-forming materials are deposited in horizontal layers
Down
- 1. a principle stating that geologic processes that occur today are similar to those that occurred in the past
- 2. the principle that in undisturbed rock layers, the oldest rocks are on the bottom
- 3. a fossil representative of a species that existed on Earth for a short length of time, was abundant, and inhabited many locations
- 5. the principle that if one geologic feature cuts across another feature, the feature that it cuts across is older
- 6. the extinction of many species on Earth within a short period of time
- 8. the preserved remains or evidence of past living organisms
- 12. a rock or sediment layer with distinctive characteristics that make it easily identifiable in correlation