Rock Layers and Continental Drift 26

Reviewing: Continental drift and relative dating.

Warm Up: Create what if, why, or how questions about the following diagram.

​Laptops

Review: Relative Dating and Continental Drift.

By Teacher at IS 93

The earth moves!

Our earth moves! We have many pieces of evidence for this some we can even feel; like earthquakes. So what is causes the movement? Magma! Deep in the Earth, molten rock churns as it heats and cools in convection currents. This moves the crustlike plates on top, and even creates and new and destroys old plates. *VIDEO TIME*

​If an intrusion or a fault cuts through existing rocks, the intrusion/fault must be YOUNGER than the rock it cuts through.

Think About it: Can you cut a cake or put icing on before the cake is made?

Layers of the Earth show us:

• its history

• fossils of animals and plants from long ago

Rock layers in different places can be correlated, or matched up, by matching the rocks and fossils in the layers.

​

Correlation

Multiple Choice

Which rock layer most likely contains fossils of the most recently evolved organisms?

• 1
• 2
• 3
• 4

Multiple Choice

Which of the following organisms formed last on Earth?

• Jellyfish
• Shark
• Lizards
• Horses

Multiple Choice

Which layer formed first?

• Rock Layer W
• Rock Layer X
• Rock Layer Y
• Rock Layer Z

Multiple Choice

The diagram shows the fossils in two different sections of rock found in opposite sides of a canyon. Which layer in rock section one is approximately the same age as layer X in rock section two?

• layer 1
• layer 2
• layer 3
• layer 4

Multiple Choice

The picture shows four different rock layers in a hillside. What is the best evidence that one of these layers of rock was formed under an OCEAN?

• The thickness of the sedimentary rock layers.

• The type of fossils found in the sedimentary rock layers.

• The texture of the sedimentary rock layers.

• The height of the sedimentary rock layers.

Multiple Choice

Which rock layer is probably the youngest?

• A

• B

• C

Multiple Choice

A fish fossil was found in layer A. What does this tell us about the possible history of this area?

• Fish used to live on land there

• This area has always been land

• That area used to be underwater

• Layer A is currently covered in water

Multiple Choice

Which rock layer contains the newest fossils?

• F
• E
• B
• C

Continental Drift

Alfred Wegener

German meteorologist who first proposed the theory of continental drift.

Pangea

The large
landmass

that

included

all of

Earth’s
present-

day

continents

Evidence for

Continental Drift

1. Shape of the Continents

● The continents fit together like puzzle pieces.
● 1858: Antonio Pelligrini depicted Africa & South

America connected.

2. Fossils

● Fossils of the same organisms were found on

different continents.

● Mesosaurus found in Africa & South America,

but couldn’t swim across the ocean.

3. Rock Evidence

● Existing mountain

ranges separated by
oceans had identical
mineral content.

● Example: Appalachian

mountains in US &
Caledonian mountains in
British Isles

5. Coal Deposits

● Coal deposits found in temperate & polar regions

even though coal is formed in tropical regions.

Evidence #6 - Glacial Scars in Africa!

Theory:

The reason for Continental Drift: Convection Currents in the Mantle

Multiple Choice

The movement of the plates is caused by ___.

• Magnets

• Asteroids

• Changes in the mantle

Multiple Choice

Name the type of heat transfer shown in the picture.

• convection

• conduction

• radiation

Multiple Choice

What does the theory of continental drift state?

• The continents were once joined in a super-continent and have moved over time
• Continents are stationary and do not move
• The Earth is broken into lithospheric plates that move due to convection currents
• none of the above

Multiple Choice

What is represented by the picture? 

• Sea-floor spreading
• Pangea
• How the continents are arranged today
• Volcanoes

Multiple Choice

Alfred Wegener thought which 2 continents looked like puzzle pieces that could fit together?

• Antarctica and Asia

• South America and Africa

• South America and Australia

• Africa and Pangaea

Multiple Choice

What does the presence of coal beds in Antarctica indicate?

• A warmer and wetter past climate in Antarctica

• A colder and drier past climate in Antarctica

• The presence of ancient forests in Antarctica

• The absence of any past climate change in Antarctica