Lauren Strickland Student Exploration: Building Pangaea Date: 3/12/14 Vocabulary: continental drift, fossil, glacier, ice age, landmass, Pangaea, superscription Prior Knowledge Questions (Do these BEFORE using the Gizmo. ) 1. Antarctica is a frozen land, so cold and icy that no trees can grow there. Yet scientists have discovered fossils (remains preserved In rock) of ancient trees In Antarctica. What do you think this means? That Antarctica was once a part of the continents & it was separated by continental drift. . The Himalayas in central Asia are the tallest mountains in the world. But fossils of seashells can be found high in these mountains, far from any ocean. How do you think they got there? Molten rock coming out of the earth piled up & made the mountains from under the water. Gizmo Warm-up 1. The Gizmo allows you to drag and rotate all the major landmasses on Earth. To drag a landmass, grab it in the middle. To rotate a landmass, grab it near the edge. Learn the names of landmasses by holding the cursor over the landmass for a few seconds.
Mark where you live. Drag an arrow from the purple bar at left to your location. 2. Test your geography skills. Drag and rotate landmasses randomly until you make a big mess. Then try to move them back to their original positions. When you have made the best map you can, click the camera icon in the upper right corner to take a snapshot. Then open a blank word-processing document and choose Paste. Right. Activity A: Solving the puzzle Get the Gizmo ready: If necessary, click Reset. Check that the Evidence shown is None.
Introduction: In 191 5, a German scientist named Alfred Wagoner (PAY-ugh-nerd) proposed the theory of continental drift. According to this theory, the landmasses once were Joined into a superscription called Pangaea. The landmasses then slowly drifted to their current positions. Question: What did Pangaea look like? 1 . Observe: Drag South America close to Africa. Look at their coastlines. What do you notice? The two continents connect almost perfectly. 2. Explore: Try to fit all the landmasses together like a puzzle. As much as possible, avoid overlapping landmasses.
When you are satisfied, take a snapshot and paste it into your document. Label this map “fit of continents. ” Fit of Continents: 3. Analyze: Look at your map of Pangaea. A. How well do the continents fit together? They don’t fit very well. B. Is it a perfect fit? Explain. No. They don’t connect in certain places. C. Think about how the landmasses got from where they were to where they are today. Does it seem realistic that the landmasses could have moved like this? Explain. Not like this. It seems too disjointed to fit. 4. Compare: If possible, present your map of Pangaea to your classmates and teacher.
Look at other maps, and talk about each one. A. Are the maps very similar or very different? I didn’t see any other maps. Would you have believed his theory that the continents had moved? Explain. Probably not. The coasts don’t match in this map. Activity B: Fossil and rock evidence Click Reset. Under Evidence choose Fossils. Question: What do fossils and rocks tell us about Pangaea? 1 . Observe: The brown areas in the Gizmo show where fossils of Lustrously have been found. Lustrously looked a bit like a dinosaur, but lived in a time before dinosaurs. A.
On which landmasses did Lustrously live? Africa & Eurasia. B. Lustrously probably couldn’t swim very far. How might the locations of Lustrously fossils be seen as evidence that the continents were once together? Where the fossils are on the diagram match the ones in South America. 2. Explore: Use the fossil evidence to help you make a new map of Pangaea. When the map is complete, take a snapshot and paste it into your document. Label this map “fossil evidence. ” Fossil Evidence How well do the landmasses fit together this time? The “pre-dinosaurs” match each other. . Revise: Now under Evidence choose Rocks. The purple areas are mountains that formed when landmasses collided 450 million years ago. The orange areas show rocks that formed about 2 billion years ago. Adjust your map using this evidence, and then paste a snapshot of this map into your document. Label this map “rock evidence. Rock evidence: 4. Compare: If possible, compare your map to those of your classmates. A. How similar are the maps? I didn’t see any other maps. B. If Wagoner showed you this evidence, would you have believed his theory?
Explain. Close together. 5. Extend your thinking: Click Reset and watch India closely. The Himalayan Mountains are found on the border of India and Eurasia. How do you think these mountains were formed? India and Eurasia, driven by plate movement, collided. Because both these continental landmasses have about the same rock density, one plate could not be subjected under the other. The pressure of the impinging plates could only be relieved by thrusting skyward, contorting the collision zone, and forming the Jagged Himalayan peaks.
Activity C: Ancient ice sheets Under Evidence choose Glaciers. Introduction: Glaciers are large, slow-moving sheets of ice. During ice ages, glaciers formed at the North and South Poles and spread out to cover large areas. Question: What does evidence of glaciers tell us about Pangaea? Glacial deposits of the same age & structure are found throughout the southern continents, so Pangaea fit. 1. Observe: The white areas are places that show evidence off massive ice sheet hat existed around 250 million years ago. A. Which landmasses show evidence of ancient glaciers?
Australia, South America, Africa. B. Would you expect to find large glaciers on all of these landmasses today? Explain. No. They’re near the equator. 2. Explore: Drag the landmasses together to form a map of Pangaea. Try to line up the white areas on each continent. You can use the fossil and rock evidence as well if you like. Paste a snapshot of this map into your document, labeled “Glacial evidence. ” Glacial evidence: 3. Analyze: Choose Glaciers (if necessary) and look at the white regions. Does this tatter make more sense now? Explain. A bit.
The coasts fit better. 4. Extend your thinking: As glaciers moved away from the poles, rocks stuck to the bottom of the ice were dragged over the ground. This left scrapes and scratches on rock outcrops that can still be seen today. The scratches show which direction the glaciers moved. A. Look at the arrows that show the direction of glacial scratches. What is the pattern? It’s in a complete circle. B. Which landmass do you think was located over the South classmates. Africa. Its glacial evidence goes in both directions. Assessment Questions: 5/5