Across
- 6. A long cylinder of ice obtained from drilling through ice caps or ice sheets; used to study past climates
- 8. The process in which a radioactive isotope tends to break down into a stable isotope of the same element of another element.
- 10. The scientific study of the origin, history, and structure of Earth and the processes that shape Earth.
- 11. The standard method used to divide Earth's long natural history into manageable parts.
- 12. Principle that geologic processes that occurred in the past can be explained by current geologic processes.
- 14. A principle that states that younger rocks lie above older rocks if the layers have not been disturbed
Down
- 1. Any method of determining whenether an event or object is older or younger than other events or objects
- 2. A method of determining the absolute age of an object by comparing the relative percentages of a radioactive (parent) isotope and a stable (daughter) isotope.
- 3. The weather conditions in an area over a long period of time
- 4. The trace or remains of an organism that lived long ago, most commonly preserved in sedimentary rock
- 5. Any method of measuring the age of an event or object in years
- 7. The time required for half of a sample of a radioactive isotope to break down by radioactive decay to form a daughter isotope.
- 9. An automated system for capturing, storying, retrieving, analyzing, manipulating and displaying geographic data.
- 12. A break in the geologic record created when rock layers are eroded or when sediment is not deposited for a long period of time
- 13. fossilized structure, such as a footprint or a coprolite, that formed in sedimentary rock by animal activity on or within soft sediment