Name: ________________________ Period 1 2 3 4 5 6
CK12 Reading Notes for 11.4 to 11.6
11.4 Principles of Relative Dating
Use this video resource to answer the questions that follow.
https://www.youtube.com/watch?v=z93fKmQqPW0 Start at 1:23
1. What do you determine when you're doing relative dating? 2.
What are you not determining?
3.
What is the Law of Superposition? 4.
What is the exception?
5.
What is the Law of Original Horizontality? 6.
If rocks are not horizontal what does that mean?
7.
What is the Law of Cross­Cutting Relationships?
8.
What is the Law of Inclusions?
9.
What is an unconformity? 10. What can cause an unconformity?
11. What does an angular unconformity look like? 12. What does this indicate?
13. What happened during an unconformity and how do we know that?
14. How do you know where there is a disconformity?
15. What happened to create a nonconformity? 16. What can you look for to identify a nonconformity?
Reading Review
17. How do Steno's laws help geologists to decipher the geological history of a region?
18. What is the principle of faunal succession?
19. Why does just about every geology textbook use the Grand Canyon as the example in the sections on geological history?
11.5: Determining Relative Ages
Use the video resource below to answer the questions that follow.
https://www.youtube.com/watch?v=5UFXxap7g9I
20. What does relative dating give you? What doesn't it give you?
21. What is the order of rock layers and events in the first rock section shown?
22. What is the order of rock layers and events in the second rock section shown?
23. What is the order of rock layers and events in the third rock section shown?
24. What is the order of rock layers and events in the fourth rock section shown?
25. What is the order of rock layers and events in the fifth rock section shown?
26. What is the order of rock layers and events in the sixth rock section shown?
Reading Review
27. What is relative age? 28. How does it differ from absolute age?
29. Why do the principles of relative dating not indicate the absolute age of a rock unit?
30. Under what circumstances would a rock unit with an older fossil be above a rock until with a younger fossil?
11.6: Correlation of Relative Ages
Use the video resource below to answer the questions that follow.
https://www.youtube.com/watch?v=M4aL96AKKbY To see where these two canyons are in the geology of this potion of southern Utah shown see in the drawing of the Grand Staircase at the top of this concept.
31. What does the rock that forms the hoodoos of Bryce Canyon tell geologists about the environment at the time the sediments were deposited?
32. Why are the rocks at Bryce Canyon orange?
33. What happened when the Colorado Plateau rose?
34. How were the hoodoos created for the most part?
35. What is the rock that creates the white cliffs at Zion? 36. Why are the sands at angles?
37. When was that portion of Utah a giant sand dune? 38. Why are there dunes stacked on top of dunes?
Reading Review
39. What features must the iridium layer that dates to around 66 million years ago have to be a key bed?
40. Why are microfossils especially useful as index fossils?
41. What is the process of correlation?
Summary Paragraph ­ type out and turn in to Turnitin.com
Write a 7 sentence paragraph that explains how scientists determine the age of a fossil. Use the vocabulary you learned above and bold these words in your text: horizontality, superposition, disconformity, nonconformity, faunal succession, relative age, iridium, absolute age, index fossil, canyons, crosscutting, erosion, intrusions, micro­fossils. To prepare for your summary paragraph, write a sequence of 5 ideas that you will use as an outline in your paragraph. Remember to include the vocabulary you learned above.
1.
2.
3.
4.
5.