Unraveling Earth's Past

You observe a rock outcrop with layers of sedimentary rock. According to the Principle of Original Horizontality, how were these rock layers originally deposited?

• Vertically

• Horizontally

• At a random angle

• In a circular pattern

In a sequence of undisturbed sedimentary rocks, where is the youngest layer likely to be found?

• At the bottom

• In the middle

• At the top

• Outside the sequence

Tags

NGSS.MS-ESS1-4

If a fault cuts across several layers of rock, what can you infer about the relative age of the fault according to the Principle of Cross-Cutting Relationships?

• The fault is older than the layers it cuts through.

• The fault is the same age as the layers it cuts through.

• The fault is younger than the layers it cuts through.

• The age of the fault cannot be determined.

What is an unconformity in a rock sequence?

• A layer of rock that has been turned upside down

• A gap in the geological record where rock layers have been removed by erosion

• A place where rocks have been folded or tilted

• A sequence of rocks that have not been disturbed

Tags

NGSS.HS-ESS2-1

Which of the following best describes the Principle of Superposition?

• Older rocks are on top, and younger rocks are at the bottom.

• Younger rocks are on top, and older rocks are at the bottom.

• Rocks on the sides are older than the rocks in the center.

• There is no specific order to the ages of rocks in a sequence.

Tags

NGSS.MS-ESS1-4

What is the significance of index fossils in relative dating?

• They indicate the absolute age of the rocks.

• They are found in all rock layers.

• They show the direction of magnetic fields in the past.

• They allow for the correlation of rock layers from different locations.

If an igneous intrusion is found within a sequence of sedimentary rock, what can be said about the relative ages of the rock and the intrusion?

• The intrusion is older than the sedimentary rock.

• The sedimentary rock is older than the intrusion.

• The intrusion and the sedimentary rock are the same age.

• The relative ages cannot be determined.

Tags

NGSS.MS-ESS1-4

What does an angular unconformity indicate about the geological history of the area?

• The area has experienced continuous deposition.

• The area has been affected by a volcanic eruption.

• The area has experienced deposition, tilting, and erosion.

• The area has been affected by an earthquake.

Tags

NGSS.HS-ESS2-1

In a rock outcrop, you find a layer of sandstone that is overlain by a layer of volcanic ash. Using the Principle of Superposition, which layer is younger?

• The sandstone layer

• The volcanic ash layer

• Both layers are the same age

• It is impossible to determine which layer is younger

Tags

NGSS.MS-ESS1-4

A limestone layer contains fossils of a marine organism known to have lived in a specific geological time period. This limestone layer is most likely to be used as:

• An index fossil for correlating the age of rock layers.

• A source for radiometric dating.

• Evidence of an angular unconformity.

• A marker for the youngest rock layer.

Tags

NGSS.MS-ESS1-4

NGSS.MS-LS4-1