ICE AGE

3. a glacier that forms on land
4. the circulation of water through the hydrosphere from earths surface to the atmosphere and back
8. a glacier that forms on mountains
11. the comparison of fossils in different rock layers to determine how old a rock or fossil is
12. certain fossils known to exist in a particular place and time
15. a global climate marked by long periods of cold temperatures that cause glacial formation and expansion
16. when a species no longer has living members in existence.

1. a flowing mass of ice and snow
2. the breakdown of rock into smaller peices from exposure to wind, water, gravity, etc
5. record all of the fossils that have ever been found
6. the eroded sediment that is depositied as glaciers retreat and expand
7. the conditions of the atmosphere
9. the transport of sediment by wind, water, and gravity
10. the average weather in a location for over 30 years or more
13. the remains of ancient animals and plants, the traces or impressions of living things from past geologic ages, or the traces of their activities
14. cylinders of ice drilled out of glaciers that contain layers of snow, dust, volcanic ash, etc