Review Questions from class on Tuesday, December 8th.

1. Review Questions Chapter 8: Relative Dating, Absolute Dating, Fossils

2. This principle states that geologic processes are the same today as they were in the past but the RATES of the processes vary over time Uniformitarianism

3. This branch of Earth Science studies the history of the Earth Earth Science

4. What does a Paleontologist study? Fossils

5. When you determine whether an object or event is older or younger than other objects/events, you are finding the object’s ___________ Age. Relative

6. This law states that younger rocks lie above older rocks in undisturbed rock layers. Superposition

7. A break in the earth’s crust along which blocks of crust slide relative to one another Fault

8. Molten rock from Earth’s interior that squeezes into existing rock layers and cools Intrusion

9. This type of rock disturbance occurs when rock layers bend and buckle from Earth’s internal forces Folding

10. This disturbance occurs when internal forces in the earth slant rock layers without folding them Tilting

11. Hardened tree sap that sometimes has the preserved remains of insects Amber

12. The number of years an object has existed Absolute Age

13. Remains or traces of animals or plants that lived in past geologic times Fossils

14. This occurs when an organism’s tissues are completely replaced by minerals Petrification

15. Any naturally preserved evidence of an animal’s activity Trace Fossil

16. A type of trace fossil that is made from preserved animal feces or dung & can provide information about the habits/diet of animals that left them Coprolite

17. An empty space/cavity in rock where a plant or animal was buried Mold

18. A replica of an object that is created when sediment fills a mold and becomes rock Cast

19. The boundary between a set of tilted rock layers and a set of horizontal layers Angular Unconformity

20. Atoms of the same element that have different numbers of neutrons Isotopes

21. Fossils of organisms that lived during a short, well-defined time span and are only found in rock layers of a particular geologic age Index Fossils

22. The earth’s age, according to geologists 4.6 Billion years old

23. The law that states that faults/intrusions are always younger than the rock layers they cut through Law of Crosscutting Relationships

24. Saying one rock is older or younger than another rock but not saying its age in years Relative Age

25. Principle that states that sedimentary rocks left undisturbed will remain in horizontal layers Principle of Original Horizontality

26. A break in the geologic rock record Unconformity

27. List 3 methods of absolute dating besides Radiometric Dating Rates of Erosion Rates of Deposition Varve Count

28. List two reasons Radiometric Dating is the most accurate method Doesn’t depend on Environment Rates don’t vary over time

29. The original radioactive isotope Parent Isotope

30. The newly formed, more stable isotope that forms during radioactive decay Daughter Isotope

31. The time it takes for ½ the mass of parent isotope to decay into its daughter isotope Half Life

32. If you have 16 g of radioactive parent isotope, how much parent/daughter isotope will you have after 3 half lives? 2 g of Parent 14 g of Daughter

33. This parent isotope decays into Lead-206, has a half life of 4.5 billion years, and is used to date rock that is really old Uranium 238

34. This parent isotope decays into Nitrogen-14, has a half life of 5,730 years, and is used to date rock that is relatively young Carbon-14

35. Sue was found in this state South Dakota

36. Sue was the most _______ T.rex ever found Complete

37. WHO was Sue the T.rex named after? The woman who found her

38. Who bought Sue and for how much? Chicago’s Field Museum $8 Million