Petroski - Geologic Time and Stratigraphy Practice

During a class project on the history of life on Earth, Daniel and Ava are trying to determine when the first fish appeared in the fossil record. According to their research, which period should they focus on?

• Permian

• Jurassic

• Cambrian

• Silurian

Answer explanation

The first fish appeared during the Cambrian period, which is known for the emergence of many marine life forms, including early fish. The other periods listed came later in the geological timeline.

Tags

NGSS.MS-LS4-1

On the Geologic Time Scale diagram, click the Era that we currently live in.

Tags

NGSS.MS-ESS1-4

According to this depiction of the Geologic Time Scale, what Period began 250 million years ago?

• Mesozoic

• Triassic

• Permian

• Paleozoic

Answer explanation

The Triassic Period began approximately 250 million years ago, following the Permian Period. It is the first period of the Mesozoic Era, making it the correct answer.

Tags

NGSS.MS-ESS1-4

According to the Law of Superposition, the rock layer closest to the surface of the Earth is younger than the rock layers below it.

• True

• False

Answer explanation

The Law of Superposition states that in undisturbed rock layers, the oldest layers are at the bottom and the youngest are at the top. Therefore, the statement is true: the rock layer closest to the surface is indeed younger.

Tags

NGSS.MS-ESS1-4

Which layer is the oldest?

• A

• B

• C

• D

Answer explanation

Layer D is the oldest because, in geological terms, the oldest layers are typically found at the bottom of a sequence. As layers accumulate over time, the most recent layers are deposited on top of the older ones.

Tags

NGSS.MS-ESS1-4

Which layer is the youngest?

• A

• B

• C

• D

Answer explanation

Layer A is the youngest because, in geological terms, the youngest layer is typically the one that is on top, having been deposited last. Therefore, A is the correct choice.

Tags

NGSS.MS-ESS1-4

During a geology field trip, Emma and Rohan are examining rock layers. Did the lava flow occur before or after the Granite Dike?

• Before

• After

Answer explanation

The Granite Dike is an intrusion that forms when magma cools and solidifies underground. The lava flow occurred after the Granite Dike, as it is typically younger than the rock it intrudes into.

Tags

NGSS.MS-ESS1-4

Drag and drop the layers below to the correct column.

Groups:

(a) Older than the Granite Dike

,

(b) Younger than the Granite Dike

• Limestone #4

• Sandstone #2

• Shale #3

• Lava Flow

• Shale #1

Tags

NGSS.MS-ESS1-4

Order the rock layers below from oldest to youngest

• E

• C

• F

• B

• D

Tags

NGSS.MS-ESS1-4

Place the layers in the correct category below:

Groups:

(a) Younger than layer A

,

(b) Older than layer A

• E

• D

• G

• C

• F

• B

Tags

NGSS.MS-ESS1-4