The document discusses determining the relative ages of rocks and fossils by examining rock layers. It explains that younger rocks are found higher in rock layers than older rocks due to the law of superposition. This allows scientists to deduce the relative ages of fossils found in different layers, with those in lower layers being older. Examples are given of using rock layers to determine which fossils are oldest and youngest.

1. 4L
*copy down things in black

2.  Maya is older than Anna
Nikki is older than Cheryl
Cheryl is older than Maya
Who is the oldest?

3.  Maya is older than Anna
 Nikki is older than Cheryl
 Cheryl is older than Maya
Who is the oldest?
youngest
oldest

4.  Maya is older than Anna
 Nikki is older than Cheryl
 Cheryl is older than Maya
Who is the oldest?
4
2 3 1

5. HOW DO WE KNOW HOW OLD
THE EARTH IS AND HOW
LONG AGO THINGS
HAPPENED ON EARTH?

6. WHAT IS RELATIVE
DATING?
Relative Age—how old something is compared to something
else
 Example: I am older than John, but younger than Mary.

7. ROCK LAYERS
 We can “read” rock layers to determine relative age of fossils and
rocks

8. ROCK LAYERS
Which fossil is the oldest?
Which fossil is the youngest?
A
B
C
D

9. ROCK LAYERS
Law of Superposition younger rocks are on top, older rocks are on
bottom
A
B
C
D

10. SKETCH THIS!

11. SKETCH THIS!
youngest
oldest

12. WHAT IF IT’S NOT NEAT
LAYERS?

13. WHAT IF IT’S NOT NEAT
LAYERS?

14. WHAT IF IT’S NOT NEAT
LAYERS?

15. TRY IT YOURSELF!

16. COMPARING ROCK LAYERS
AND FOSSILS

17. B
C