Unit 2 Lesson 2: Relative Dating

Open Ended

An example of something old...

Open Ended

An example of something young...

Open Ended

An example of something that is horizontal...

Open Ended

An example of something older than you...

Multiple Choice

The hardened remains of a living thing that died long ago.

• fossil

• extinct

• endangered

• minerals

Multiple Choice

Which type of rock are most fossils found?

• sedimentary rock

• metamorphic rock

• igneous rock

• fossils

Multiple Choice

Which of these is the best indication of the relative age of a rock layer?

• The chemical make-up of the layer

• The thickness of the layer

• The position of the layer compared to another layer

• The distance of the layer extending over Earth

Multiple Choice

Using Absolute and Relative Age

This tiny speck is a crystal that was found in a sandstone rock in Australia. It's about 4.2 billion years old. The person holding it is Simon Wilde, who discovered it in 1984. Is this an example of Relative Age or Absolute Age

• Absolute Age

• Relative Age

Multiple Choice

Relative age of a rock is the number of years that have passed since the rock formed?

• True

• False

Multiple Choice

This coin is the newest in my collection .

Is the statement describing (A) absolute age or (R) relative age?

• Relative Age

• Absolute Age

Multiple Choice

Summarize the Law of Superposition

• The youngest rocks are located at the bottom of the rock layers

• The oldest rocks are located at the bottom of the rock layers

• The ages of the rocks are mixed between the layers of the rock

• The ages of all the rocks are the same throughout all the layers

Multiple Choice

Which layer is the oldest?

• A

• B

• C

• D

Multiple Choice

What does the Law of Original Horizontality mean?

• Sedimentary Rocks nautrally form vertical layers and then they fall horizontally

• Sedimentary Rocks form in horizontal layers

• Sedimentary Rocks form vertical and horizontal layers

• Sedimentary Rocks cannot change direction once formed

Multiple Choice

Using the information from the previous slides. Which Rock layer is the oldest?

• 1

• 2

• 3

• 4

Multiple Choice

Using the information from the prevous slides. Which rock layer is the youngest?

• 1

• 2

• 3

• 4

Multiple Choice

Which of the following correctly lists the layers in order from oldest to youngest?

• A, B, C, D, E
• E, B, C, D, A
• E, D, C, B, A
• C, B, A, D, E

Multiple Choice

Which of the following is true?

• A fault is younger than the rock layers that it goes through.

• A fault is older than the rock layers that it goes through.

• The rock layers are younger than the fault that cuts through it.

Multiple Choice

Which of the following is true?

• An igneous intrusion is older than the rock layers that it goes through.

• An igneous intrusion is younger than the rock layers that it goes through.

• The rock layers are younger than the intrusion that cuts through it.

Multiple Select

What are two ways that a rock layer can cause a gap in the geologic record?

• when an intrusion occurs

• when a rock layer is eroded

• when a fault breaks and separates rock layers

• when sediment is not deposited for a very long time

Multiple Choice

_{Which rock layer contains the newest fossils?}

• F
• E
• B
• C

Multiple Choice

To be considered an index fossil, it had to have lived for a relatively short period of time.

• True
• False

Multiple Choice

The fossil record shows that horseshoe crabs have existed with very little change for about 1 billion years. Would horseshoe crabs be useful as an index fossil?

• Yes, because they were around for a very long time

• No, because horseshoe crabs can never be used as index fossils

• No, because they were around for TOO LARGE of an amount of time

• Yes, because horseshoe crabs can always be used as index fossils

• Relative dating can also be done by comparing the relative ages of rock layers in different areas. ​

• A geologic column is an ordered arrangement of rock layers that is based on the relative ages of the rocks with the oldest rocks at the bottom of the column.

• Not an actual rock layer, but a comparison of two different rock layers.​

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​Geologic Column

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