Cross Section Analysis Rock Layers

The cross section on the right shows sedimentary rock layers containing fossils.

Assuming that these rock layers have not been overturned, which fossil is in the layer that was formed most recently?

• z

• z

Tags

NGSS.MS-ESS1-4

The cross section on the right shows fossils and the rock layers in which they are found. Crustal movement has not displaced the rock layers.

Which fossil is considered the oldest in the cross section shown?

• armored fish

• early horses

• dinosaurs

• trilobites

Tags

NGSS.MS-ESS1-4

NGSS.MS-LS4-1

Base your answers to questions 68 and 69 on the reading passage and diagram on the right and on your knowledge of science.

Preserved in Amber

Sap is a substance secreted by some trees. Many years ago, plants and small animals were caught in the sap on the trees. Sap hardens and turns into a clear substance called amber. The plants or animals are preserved as fossils in the amber. Part of a plant preserved in amber is shown below.

Explain why fossils are important to scientists. [1]

Tags

NGSS.MS-LS4-1

NGSS.MS-LS4-2

Explain why plant fossils found in amber, such as the one shown, are not usually found in volcanic rocks. [1]

Base your answers to questions 49 and 50 on the cross section below and on your knowledge of science.

The cross section shows sedimentary rock layers containing fossils. The rock layers have not been overturned since they formed.

Explain why the trilobites are considered to be the oldest fossil in this diagram. [1]

_______________________________________________________

Tags

NGSS.MS-ESS1-4

Explain how this diagram shows that all Earth’s rock layers were not formed at the same time. [1]

Tags

NGSS.MS-ESS1-4

The diagram on the right shows a cross section of a portion of Earth’s crust that has not been overturned. Letters A, B, C, and D represent sedimentary rock layers that contain fossils.

Which rock layer contains the oldest fossils?

• A

• B

• C

• D

Tags

NGSS.MS-ESS1-4

25 The sequence below occurs over a long period of geologic time.

The sequence shows the steps involved in the formation of

• an element

• an igneous rock

• a fault

• a fossil

Tags

NGSS.MS-ESS2-3

NGSS.MS-LS4-1

Base your answers to questions 60 and 61 on the diagram on the right and on your knowledge of science. The diagram represents a cross section of several layers of sedimentary rock that have not been overturned. Each layer contains fossils.

Explain why the fossils in rock layer A are more likely to resemble life-forms that exist today

Tags

NGSS.MS-LS4-1

NGSS.MS-LS4-2

State one conclusion that many scientists have made about Earth’s past by studying fossils. [1]

Tags

NGSS.MS-LS4-1