Relative Dating Homework
NAME:
1. In your own words, what is the Law of Superposition?
2. What is the difference between relative and absolute age of a rock?
3. How is the Law of Superposition an example of relative dating?
4. Draw three rock layers. Label the layers from oldest to youngest using the Law of Superposition.
5. If a geologist digs into the Earth’s crust for 500 meters, which depth would contain the oldest rocks and fossils?
a. 50 meters
c. 250 meters
b. 100 meters
d. 500 meters.
*WHY?
6. Why are igneous intrusions (principle of cross-cutting relationships) younger than the layers they cut through?
DRAW IT!
7. How does unconformity change a scientist’s understanding of the history of Earth?
A) It reduces understanding because rock layers representing thousands or millions of years are missing
B) It increases that understanding because the changes in the positions of rock layers show how forces acted
on Earth
C) It reduces understanding because fossils have been removed from an unconformity
D) It increases understanding because an unconformity contains rock layers that are absent in other areas
8. The diagram shows a portion of Earth’s crust. Letters A, B, C, and D
represent sedimentary rock layers. Which rock layer contains the oldest
fossils?
A) A
B) B
C) C
D) D
9. Draw a picture of a rock layer with inclusions. Label the oldest and youngest layers.
10.If a layer of sandstone is in contact with a mass of granite that contains small pieces of the sandstone,
which rock is older?
a. the sandstone
b. the granite
c. Both are the same age.
d. It is not possible to determine which rock is older from this information.
11. Use the diagram below to list layers from youngest to oldest. Be sure to explain which principles you
used to determine the relative age of layers.
Youngest
Oldest
Which principles did you use to determine
the relative ages of the layers?
11. Using the diagram to the right, label
layers A-D from youngest to oldest.
B
Youngest
C
D
Oldest
A
Which principles did you use to determine
the relative age of the rock layers?
A
B
C
D