The Theory of Continental The Theory of Continental DriftDrift

Continental Drift TheoryContinental Drift Theory

• Proposed by Alfred Wegener in 1912

• 250 million years ago, all of the continents were combined into one super-continent called “Pangaea”

• The continents gradually drifted apart to where they are today

Evidence to Support the TheoryEvidence to Support the Theory

““Puzzle Pieces”Puzzle Pieces”

• Continents look like they could be part of a giant jigsaw puzzle

Distribution of FossilsDistribution of Fossils

• Plant and animal fossils found on the coastlines of different continents

Sequence of RocksSequence of Rocks

• Same rock patterns found in South America, India, Africa, Antarctica and Australia

Ancient ClimatesAncient Climates

• Tropical plant remains (coal deposits) found in Antarctica

• Glaciation in Africa, South America, India, and Australia during the same time

Problems With The TheoryProblems With The Theory

• No mechanism for movement of continents

• Wind and currents could possibly move fossils

• Theory was not accepted by scientists

Your job is to …..Your job is to …..

• Using the evidence presented by the ‘continental drift’ theory, you will reconstruct what you think Pangea looked like more than 200 million years ago.

• Puzzle piece key:– F = fossils– M =mountain belts– G = glacial deposits

Pangaea QuestionsPangaea Questions

• Explain how mountain chains provided evidence for the existence of Pangea.

• Explain how fossils provided evidence for the existence of Pangea.

• Explain why India has evidence of glaciers that are more than 240 million years old even though it is located near the equator.

1= North America 2= Eurasia 1= North America 2= Eurasia 3=South America 4=Africa 5=India 3=South America 4=Africa 5=India

6=Antarctica 7=Australia6=Antarctica 7=Australia