Cross Sections (Earth's Outer Layer, Fossils, Relative Dating)

Understanding Cross Sections
(Relative Dating and Earth's Outer Layer)

Open Ended

What observations do you have about the four cross sections? Did you notice any patterns?

​(Fossils are assumed to be the same age as the rock they are found in)

Multiple Choice

How old do scientists age fossils?

• They assume the fossil is older than the rock it's in.

• They assume the fossil is the same age as the rock it's in.

• They assume the fossil is younger than the rock it's in.

• The fossil's age is unrelated to the rock it's in.

Multiple Choice

Earth's Outer Layer is...

• mostly water.

• made of hard solid rock.

• made of soft solid rock.

• covered in sand.

Multiple Choice

Which geological law states that layers found deeper in the ground are older than layers found closer to the surface?

• Law of Original Horizontality

• Law of Cross Cutting Relationships

• Law of Superposition

• Law of Gravity

Multiple Choice

How do scientists learn about rock layers close to the surface?

• They just make it up

• Dig deep and wide holes out of the earth

• Cut the Earth in Half

• Drill for core samples

Multiple Choice

True or False: A rock or process that cuts through another rock is older than the rock it cuts through.

• True

• False

Multiple Choice

Which rock formation in the image is the oldest?

• A

• B

• C

• D

Multiple Choice

Which rock formation is older than E and Younger than C?

• A

• D

• F

• J

​"Steno and the Shark"

Multiple Choice

What are tongue stones?

• Fossilized teeth of ancient sharks

• Shark tongues

• Rocks that grew inside rocks

• Mud and sand

Multiple Choice

How did Steno describe the formation of rocks?

• They form randomly

• They form in layers, with the oldest at the bottom

• They form in layers, with the oldest at the top

• They form in zigzags, with the oldest in the middle

Multiple Choice

Based on the article, about how old do scientists think the earth is?

• 2000 Years Old

• 15,600 Years Old

• 257 Million Years Old

• 4.6 Billion Years Old

Multiple Choice

What are the largest units of Geologic Time?

• Eon

• Era

• Period

• Century