Chapter 4: Lesson 1 The Continental Drift Hypothesis

Make vocab cards/flaps/whatever you like for:

1.Pangaea2.Continental Drift

Make a 4-flap foldable book with 2 pieces of paper.

On your foldable…

Label “Continental Drift”

-Climate Clues-Fossil Clues-Rock Clues-Evidence Against

Chapter 4: Lesson 1 The Continental Drift Hypothesis• Nearly 100 years ago Alfred Wegener, a German

scientist, proposed that all the continents were once part of a supercontinent called Pangaea. • Over time Pangaea began breaking apart, and the

continents slowly moved to their present positions•Wegener proposed the hypothesis of continental

drift, which suggested that continents are in constant motion on the surface of Earth•Wegener observed the similarities of continental

coastlines now separated by ocean basins

Chapter 4: Lesson 1 The Continental Drift Hypothesis

South America

Africa

The Continental Drift Hypothesis- Climate Clues• Wegener thought that South America, Africa, India, and

Australia were closer to Antarctica 280 million years ago, so the climate of the Southern Hemisphere was much cooler at the time. • Glaciers covered large areas of these continents, which

is similar to the ice sheet that covers Antarctica• Wegener studied the sediments deposited by glaciers in

these countries, and discovered glacial grooves (deep scratches in rocks made as the glaciers moved across land.• The presence of an ice sheet covering Pangaea could

explain the glacial features on some continents today.

Chapter 4: Lesson 1 The Continental Drift Hypothesis

The Continental Drift Hypothesis- Fossil Clues• Animals and plants that live on different continents

can be unique to that continent.• Fossils from similar organisms have been found on

several continents separated by oceans.• This indicates that these continents may have been

connected in the past.• Fossils of a plant called Glossopteris have been

discovered in South America, India, Africa, Australia, and Antarctica.

Chapter 4: Lesson 1 The Continental Drift Hypothesis

The Continental Drift Hypothesis- Rock Clues•Wegener observed that mountain ranges and rock

formations on different continents had common origins, providing rock evidence for continental drift. • Volcanic rock that is identical in chemistry and age

has been found on both the western coast of Africa and the eastern coast of South America. • The Caledonia mountain range in northern Europe

and the Appalachian Mountains in eastern North America are similar in age, structure, and rock type.

Chapter 4: Lesson 1 The Continental Drift Hypothesis

The Continental Drift Hypothesis- What’s Missing?•Wegener’s ideas were not widely accepted until

nearly four decades later.

• Scientists questioned continental drift because it was a slow process and Wegener could not measure how fast continents moved or how they moved.

• Scientists could not understand how continents could push their way through the solid rock of the mantle and the seafloor.

The Continental Drift HypothesisFoldable• Fill in your foldable pages with supporting

information from your notes.

•When you are finished, glue your cards, notes, and your foldable into your notebook.

Tuesday Warm-Up (MUST BE IN YOUR NB)

Lesson 1 MiniLab- 20 MinsHow do you use clues to put puzzle pieces together?1) Using your scissors, cut your paper into at least 12,

but not more than 20 irregular pieces. 2) Exchange puzzles with your elbow partner and try

to put your new puzzle back together.3) Reclaim your puzzle and remove 3 pieces. 4) Exchange puzzles with another person and try to

put your new incomplete puzzle back together. 5) Answer Questions 1-3 on page 117 of your

textbook in your notebook.FINISHED? Do Ch. 4 L. 1 Review (118) in your NB

Lesson 1 ReviewIn your notebook, answer 1-8 on

page 118.

We’ll go over this in a few minutes.

Lesson 1 Review1. Pangaea- name given to a supercontinent that

began to break apart approximately 200 million years ago

2. The continental drift hypothesis suggests that continents are in constant motion on the surface of Earth.

3. The scientist that proposed that the continents move away from or toward each other is Alfred Wegener.

4. A. fossils

5. South America has moved West, or away from, Africa.6.

7. There may be similarities in the rock formations and fossils of the Appalachian Mountains and Caledonian Mountains.8. If continents continue to drift, it is totally possible that a new supercontinent will form. It is possible that Australia could be next to South America and Asia could be next to North America.

Continental Drift

Fossil Clues

Rock Clues

Map

ClimateClues