Landforms Tour. Landforms Tour. Landforms, observations, and questions. My school. Mount St. Helens. Aleutian Islands.

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1 Landforms Tour Site name Landforms Tour Landforms, observations, and questions Site name 1 My school 1 My school 2 Mount St. Helens 2 Mount St. Helens 3 Aleutian Islands 3 Aleutian Islands 4 Alaskan glaciers 4 Alaskan glaciers 5 Na Pali Coast 5 Na Pali Coast 6 Death Valley 6 Death Valley 7 Florida Keys 7 Florida Keys 8 Stone Mountain 8 Stone Mountain 9 Shenandoah 9 Shenandoah 10 Central Park 10 Central Park 11 Niagara Falls 11 Niagara Falls 12 Delta 12 Delta 13 Mississippi River 13 Mississippi River 14 Lake Ozark 14 Lake Ozark 15 Oklahoma Panhandle 15 Oklahoma Panhandle 16 Missouri River 16 Missouri River 17 Grand Tetons 17 Grand Tetons 18 Grand Canyon 18 Grand Canyon Investigation 1: Earth Is Rock No. 1 Notebook Master Landforms, observations, and questions Investigation 1: Earth Is Rock No. 1 Notebook Master

2 Desert Clouds Beach Dune Lake Plateau Landform Vocabulary Canyon Valley Meander River/Stream Floodplain Delta Mountain Island Glacier/Ice Plain Ocean Investigation 1: Earth Is Rock No. 2 Notebook Master Desert Clouds Beach Dune Lake Plateau Landform Vocabulary Canyon Valley Meander River/Stream Floodplain Delta Mountain Island Glacier/Ice Plain Ocean Investigation 1: Earth Is Rock No. 2 Notebook Master

3 Anticipation Guide Anticipation Guide Before reading the article called Seeing Earth, check off the statements with which you agree. 1. Images in Google Earth show live images of Earth as it appears right now. 2. Rocks are actual pieces of Earth. 3. Google Earth shows representations of the surface of planet Earth. 4. Earth-imaging satellites can take a picture of the whole surface of one side of Earth. Before reading the article called Seeing Earth, check off the statements with which you agree. 1. Images in Google Earth show live images of Earth as it appears right now. 2. Rocks are actual pieces of Earth. 3. Google Earth shows representations of the surface of planet Earth. 4. Earth-imaging satellites can take a picture of the whole surface of one side of Earth. After reading the article, check off the statements that were confirmed in the text. After reading the article, check off the statements that were confirmed in the text. 1. Images in Google Earth show live images of Earth as it appears right now. 2. Rocks are actual pieces of Earth. 3. Google Earth shows representations of the surface of planet Earth. 4. Earth-imaging satellites can take a picture of the whole surface of one side of Earth. 1. Images in Google Earth show live images of Earth as it appears right now. 2. Rocks are actual pieces of Earth. 3. Google Earth shows representations of the surface of planet Earth. 4. Earth-imaging satellites can take a picture of the whole surface of one side of Earth. Write a few sentences explaining how this article helped you clarify your thinking about Earth imaging. Investigation 1: Earth Is Rock No. 3 Notebook Master Write a few sentences explaining how this article helped you clarify your thinking about Earth imaging. Investigation 1: Earth Is Rock No. 3 Notebook Master

4 Mile 20 Sketch Mile 20 Sketch Investigation 1: Earth Is Rock No. 4 Notebook Master Investigation 1: Earth Is Rock No. 4 Notebook Master

5 Observations from photos Other Rock number Investigation 1: Earth Is Rock No. 5 Notebook Master Mile 20 Rock Observations Texture Investigation 1: Earth Is Rock No. 5 Notebook Master Other Color Observations from photos Mile 20 Rock Observations MILE 20 ROCK OBSERVATIONS Texture Color Rock number MILE 20 ROCK OBSERVATIONS

6 Mile 52 Sketch Mile 52 Sketch Investigation 1: Earth Is Rock No. 6 Notebook Master Investigation 1: Earth Is Rock No. 6 Notebook Master

7 Texture Observations from photos Other Rock number MILE 52 ROCK OBSERVATIONS Mile 52 Rock Observations Other Mile 52 Rock Observations Investigation 1: Earth Is Rock No. 7 Notebook Master Observations from photos Color Texture Color Rock number MILE 52 ROCK OBSERVATIONS Investigation 1: Earth Is Rock No. 7 Notebook Master

8 Shale Grand Canyon Rocks Shale 6 Colorado River Elevation of river: 853 meters Colorado River Elevation of river: 892 meters Mile 52 Mile 20 Rock ID 7 10 Rock-layer name Rock ID Rock-layer name Shale Colorado River Elevation of river: 853 meters Rock-layer name 8 9 Rock ID Investigation 1: Earth Is Rock No. 8 Notebook Master Grand Canyon Rocks 9 Rock-layer name Shale Colorado River Elevation of river: 892 meters Rock ID Mile 20 Investigation 1: Earth Is Rock No. 8 Notebook Master Mile 52

9 Correlation Questions Correlation Questions Use your Grand Canyon Rock Lineup sheet and FOSS Science Resources to answer these questions. Use your Grand Canyon Rock Lineup sheet and FOSS Science Resources to answer these questions. 1. How far apart are the sites at Mile 20 and Mile 52? 1. How far apart are the sites at Mile 20 and Mile 52? 2. What is the elevation of the river at Mile 20? 2. What is the elevation of the river at Mile 20? 3. What is the elevation of the river at Mile 52? 3. What is the elevation of the river at Mile 52? 4. Which way is the Colorado River flowing, from Mile 20 to Mile 52 or from Mile 52 to Mile 20? How do you know? 4. Which way is the Colorado River flowing, from Mile 20 to Mile 52 or from Mile 52 to Mile 20? How do you know? 5. Which rock layer is at river level at Mile 20? 5. Which rock layer is at river level at Mile 20? 6. Which rock layer is at river level at Mile 52? 6. Which rock layer is at river level at Mile 52? 7. Why do these two sites have different rock layers exposed at river level? 7. Why do these two sites have different rock layers exposed at river level? 8. Suppose you were in a boat on the river at Mile 20 and you could drill down into the rock under the river. What kind of rock would you expect to find? Why? 8. Suppose you were in a boat on the river at Mile 20 and you could drill down into the rock under the river. What kind of rock would you expect to find? Why? 9. Suppose you stopped at Mile 36 along the Colorado River in the Grand Canyon. Which rock layer would you expect to see at river level? Why? 9. Suppose you stopped at Mile 36 along the Colorado River in the Grand Canyon. Which rock layer would you expect to see at river level? Why? Investigation 1: Earth Is Rock No. 9 Notebook Master Investigation 1: Earth Is Rock No. 9 Notebook Master

10 Stream-Table Map Stream-Table Map Starting time Starting time Observation time Observation time Elapsed time Elapsed time Observe where different materials are being deposited (that is, sand, clay), and label them on the map. Observe where different materials are being deposited (that is, sand, clay), and label them on the map. Label on the map where the water is flowing fastest and where it is flowing slowest. Label on the map where the water is flowing fastest and where it is flowing slowest. Label on the map any landforms that have been created. Label on the map any landforms that have been created. Investigation 2: Weathering and Erosion No. 10 Notebook Master Investigation 2: Weathering and Erosion No. 10 Notebook Master

11 Stream-Table Questions Stream-Table Questions Refer to your Stream-Table Map as you answer these questions. Refer to your Stream-Table Map as you answer these questions. 1. Watch a grain of sand as it moves along. Describe its motion. 1. Watch a grain of sand as it moves along. Describe its motion. 2. Where are the large particles deposited? The small particles? 2. Where are the large particles deposited? The small particles? 3. Is a delta forming? Where? Why is it forming there? 3. Is a delta forming? Where? Why is it forming there? 4. What color is the water flowing into the basin? 4. What color is the water flowing into the basin? 5. Consider the Grand Canyon, and refer to the Colorado Plateau map in FOSS Science Resources. Where is the material eroded by the Colorado River deposited today? 5. Consider the Grand Canyon, and refer to the Colorado Plateau map in FOSS Science Resources. Where is the material eroded by the Colorado River deposited today? 6. Where do you think the material that was eroded by the Colorado River was deposited in the past? 6. Where do you think the material that was eroded by the Colorado River was deposited in the past? 7. Which do you think came first, the Colorado Plateau, the Colorado River, or the Grand Canyon? Support your answer with evidence. 7. Which do you think came first, the Colorado Plateau, the Colorado River, or the Grand Canyon? Support your answer with evidence. Investigation 2: Weathering and Erosion No. 11 Notebook Master Investigation 2: Weathering and Erosion No. 11 Notebook Master

12 Multimedia Stream Tables Multimedia Stream Tables Part 1: Flood Part 1: Flood 1. Describe in detail the motion of earth materials you see in a flood condition. 1. Describe in detail the motion of earth materials you see in a flood condition. Part 2: Different earth materials Part 2: Different earth materials Homogeneous = mixture of sand and clay just like the material used in class Homogeneous = mixture of sand and clay just like the material used in class Heterogeneous = mixture of sand and clay on top and bottom; layer of red clay in the middle Heterogeneous = mixture of sand and clay on top and bottom; layer of red clay in the middle 2. In which stream table is the earth material eroding faster and deeper? 2. In which stream table is the earth material eroding faster and deeper? 3. What is happening to the top sand/clay level in the heterogeneous materials? 3. What is happening to the top sand/clay level in the heterogeneous materials? 4. What is happening to the layer of red clay? 4. What is happening to the layer of red clay? 5. The bottom layer was made out of the same material as the top layer. Why didn t it erode as quickly? 5. The bottom layer was made out of the same material as the top layer. Why didn t it erode as quickly? Investigation 2: Weathering and Erosion No. 12 Notebook Master Investigation 2: Weathering and Erosion No. 12 Notebook Master

13 Sand Comparison Sand Comparison Samples Samples Homemade Homemade Beach sand Beach sand Similarities Similarities Homemade Beach Sand Investigation 2: Weathering and Erosion No. 13 Notebook Master Homemade Beach Sand Investigation 2: Weathering and Erosion No. 13 Notebook Master

14 Bryce Canyon National Park Bryce Canyon National Park Weathering and Erosion Weathering and Erosion Sheer cliffs, rocks balanced on one small is one example of physical weathering. Sheer cliffs, rocks balanced on one small is one example of physical weathering. tip, massive underground caves, and giant Physical weathering occurs when large rocks tip, massive underground caves, and giant Physical weathering occurs when large rocks sand dunes: what do all these things have in are broken into smaller rocks of the same sand dunes: what do all these things have in are broken into smaller rocks of the same common? These and other spectacular and kind. The sand you made was still the same common? These and other spectacular and kind. The sand you made was still the same fascinating landforms around the world are material as the larger piece of granite, only fascinating landforms around the world are material as the larger piece of granite, only the result of the processes of weathering smaller. The granite may have broken into the result of the processes of weathering smaller. The granite may have broken into and erosion. Weathering and erosion also the minerals that make it up, such as quartz and erosion. Weathering and erosion also the minerals that make it up, such as quartz create (and can destroy) the soils we depend and feldspar, but they are the same minerals create (and can destroy) the soils we depend and feldspar, but they are the same minerals on to grow the food we need to survive. that made up the original granite. on to grow the food we need to survive. that made up the original granite. How can weathering and erosion do all You saw that shaking the granite pieces How can weathering and erosion do all You saw that shaking the granite pieces that? Let s look at the investigations you have made them more rounded than the pieces of that? Let s look at the investigations you have made them more rounded than the pieces of done so far to get some clues about these fresh granite. The sharp edges and corners done so far to get some clues about these fresh granite. The sharp edges and corners processes. Remember, physical weathering wore away as they hit other rocks. This occurs processes. Remember, physical weathering wore away as they hit other rocks. This occurs is the breaking down of rock into smaller naturally when rocks are hit by windblown is the breaking down of rock into smaller naturally when rocks are hit by windblown pieces. The smaller pieces are called sediment. sand or rock particles in moving water. The pieces. The smaller pieces are called sediment. sand or rock particles in moving water. The Erosion is the process of transporting name for this type of physical weathering Erosion is the process of transporting name for this type of physical weathering sediment to a basin by water, wind, or ice. is abrasion. Abrasion also happens when sediment to a basin by water, wind, or ice. is abrasion. Abrasion also happens when falling rocks hit other rocks, causing them to Physical Weathering and Round Rocks When you shook the granite in a jar, little pieces broke off to become sand. This break apart. When you observed beach sand or sand in a riverbed, you could see smooth, polished sand grains. Waves and flowing water rolled 16 falling rocks hit other rocks, causing them to Physical Weathering and Round Rocks When you shook the granite in a jar, little pieces broke off to become sand. This break apart. When you observed beach sand or sand in a riverbed, you could see smooth, polished sand grains. Waves and flowing water rolled 16 Investigation 2: Weathering and Erosion No. 14 Notebook Master Investigation 2: Weathering and Erosion No. 14 Notebook Master

15 Blowing sand (sand abrasion) helped carve and smooth this sandstone canyon. Talus is evidence of a rock fall at the base of a cliff. Blowing sand (sand abrasion) helped carve and smooth this sandstone canyon. Talus is evidence of a rock fall at the base of a cliff. these sand grains around, causing them to Ice Wedging and Rock Falls these sand grains around, causing them to Ice Wedging and Rock Falls hit each other. You observed sand particles in the stream table bouncing and hitting other grains of sand as they moved along. The water carries rocks that bump off the rough edges on other rocks. The farther the sediment is carried by water, the smoother the sand grains get. No water is involved when wind transports sediment. The sand grains bang into each other, creating a frosted surface (a surface that is dull instead of shiny). Beach sand, river sand, and dune sand are all similar in at least one way the farther the weathered rocks travel and the more they get banged around, the smaller they become. When ice freezes, it expands with hit each other. You observed sand particles in the stream table bouncing and hitting tremendous force. You saw what happened other grains of sand as they moved along. when water in a jar froze and expanded. The water carries rocks that bump off the The force shattered the jar! Ice expansion rough edges on other rocks. The farther the naturally causes physical weathering when sediment is carried by water, the smoother water gets into tiny cracks in a rock. At night, the sand grains get. temperatures fall, and the water freezes, No water is involved when wind transports expands, and presses against the surrounding sediment. The sand grains bang into each rock. The crack gets bigger. During the day other, creating a frosted surface (a surface that as the temperature rises, the water thaws is dull instead of shiny). Beach sand, river and seeps farther down into the crack. Night sand, and dune sand are all similar in at least comes; the water again freezes. With repeated one way the farther the weathered rocks freezing and thawing, the crack becomes travel and the more they get banged around, larger, and eventually pieces of the rock break the smaller they become. off. Ice wedging can break rocks off the side water gets into tiny cracks in a rock. At night, temperatures fall, and the water freezes, expands, and presses against the surrounding rock. The crack gets bigger. During the day as the temperature rises, the water thaws and seeps farther down into the crack. Night comes; the water again freezes. With repeated freezing and thawing, the crack becomes larger, and eventually pieces of the rock break off. Ice wedging can break rocks off the side because a tiny crack kept enlarging until the because a tiny crack kept enlarging until the piece broke off. You may have seen the results piece broke off. You may have seen the results of ice wedging: damaged concrete sidewalks of ice wedging: damaged concrete sidewalks and curbs, and flaking bricks. and curbs, and flaking bricks. Plant roots can also cause weathering by Plant roots can also cause weathering by Round, smooth river rocks growing into cracks. The roots expand as the plant grows, breaking the rocks apart. the plant grows, breaking the rocks apart. Investigation 2: Weathering and Erosion 17 Investigation 2: Weathering and Erosion 17 Investigation 2: Weathering and Erosion No. 15 Notebook Master naturally causes physical weathering when found at the base of cliffs. These rocks fell found at the base of cliffs. These rocks fell The force shattered the jar! Ice expansion falls in the piles of jagged rocks called talus falls in the piles of jagged rocks called talus growing into cracks. The roots expand as when water in a jar froze and expanded. of a cliff. You can see evidence of these rock of a cliff. You can see evidence of these rock Round, smooth river rocks When ice freezes, it expands with tremendous force. You saw what happened Investigation 2: Weathering and Erosion No. 15 Notebook Master

16 called carbonic acid. Although this acid is too called carbonic acid. Although this acid is too weak to make limestone fizz, each slightly weak to make limestone fizz, each slightly acidic raindrop dissolves a few molecules of acidic raindrop dissolves a few molecules of limestone. Over thousands of years, limestone limestone. Over thousands of years, limestone will slowly wear away because of chemical will slowly wear away because of chemical weathering. weathering. Decaying plant material, lichens, and plant Decaying plant material, lichens, and plant roots also produce carbon dioxide and other roots also produce carbon dioxide and other weak acids. These acids dissolve in rainwater weak acids. These acids dissolve in rainwater as it moves through soil and into cracks Ice causes bricks to flake apart. Tree roots break rocks. You have probably seen tree roots that lifted in rock. caves such as Carlsbad as it moves through soil and into cracks Ice causes bricks to flake apart. in rock. caves such as Carlsbad Caverns in New Mexico and Mammoth Cave Caverns in New Mexico and Mammoth Cave in Kentucky formed as chemical weathering in Kentucky formed as chemical weathering dissolved limestone over millions of years. dissolved limestone over millions of years. This weathering creates landforms called This weathering creates landforms called karst topography. Sinkholes and caves are karst topography. Sinkholes and caves are karst landforms and are found in many karst landforms and are found in many areas, including Kentucky and Florida. The areas, including Kentucky and Florida. The limestone pinnacles found in China are limestone pinnacles found in China are also examples of karst topography. Since also examples of karst topography. Since the formation of acids requires moisture, the formation of acids requires moisture, karst topography is found in rather humid karst topography is found in rather humid environments. In more arid locations, environments. In more arid locations, limestone tends to form steep cliffs, like the limestone tends to form steep cliffs, like the ones in the Redwall in the Grand Canyon. Weak acids will even weather granite, Tree roots break rocks. You have probably seen tree roots that lifted ones in the Redwall in the Grand Canyon. Weak acids will even weather granite, and broke a sidewalk or even cracked the though at a much slower pace than limestone. and broke a sidewalk or even cracked the though at a much slower pace than limestone. foundation of a house. Granite is made of several common minerals, foundation of a house. Granite is made of several common minerals, mainly quartz, feldspar, and hornblende. Chemical Weathering Physical weathering is not the only way Quartz is very resistant to chemical weathering; feldspar is more susceptible. mainly quartz, feldspar, and hornblende. Chemical Weathering Physical weathering is not the only way Quartz is very resistant to chemical weathering; feldspar is more susceptible. rocks can be broken down. Remember how Acid slowly breaks down feldspar into clay rocks can be broken down. Remember how Acid slowly breaks down feldspar into clay the limestone fizzed when you put a drop of particles. Without feldspar to hold the granite the limestone fizzed when you put a drop of particles. Without feldspar to hold the granite acid on it? During that chemical reaction, together, the quartz crystals fall out and acid on it? During that chemical reaction, together, the quartz crystals fall out and acid dissolved a tiny amount of rock. This become sand. The durability of quartz is the acid dissolved a tiny amount of rock. This become sand. The durability of quartz is the same process takes place naturally. Tiny reason so much sand is composed mainly same process takes place naturally. Tiny reason so much sand is composed mainly amounts of carbon dioxide in the air dissolve of quartz. amounts of carbon dioxide in the air dissolve of quartz. in falling raindrops to form a very weak acid in falling raindrops to form a very weak acid Investigation 2: Weathering and Erosion No. 16 Notebook Master Investigation 2: Weathering and Erosion No. 16 Notebook Master

17 Bryce Canyon National Park, Utah Bryce Canyon National Park, Utah Vie e Ridge Park a View from the Bl Blue Parkway, North Carolina Grand Canyon National Park, Arizona Vie e Ridge Park a View from the Bl Blue Parkway, North Carolina Grand Canyon National Park, Arizona Badlands National Park Park, South Dakota Badlands National Park Park, South Dakota Yangshuo, China Yangshuo Yangshuo, China Yangshuo Investigation 2: Weathering and Erosion 19 Investigation 2: Weathering and Erosion No. 17 Notebook Master Investigation 2: Weathering and Erosion 19 Investigation 2: Weathering and Erosion No. 17 Notebook Master

18 behind. Much of the scenery in the Grand behind. Much of the scenery in the Grand Canyon is due to differential erosion. Devils Canyon is due to differential erosion. Devils Tower in Wyoming consists of hard rock that Tower in Wyoming consists of hard rock that was once covered and surrounded by softer was once covered and surrounded by softer rock. Over the past 1 to 2 million years, rock. Over the past 1 to 2 million years, the softer rock weathered and eroded away, the softer rock weathered and eroded away, leaving the column of hard rock standing. leaving the column of hard rock standing. Niagara Falls on the New York Canada Niagara Falls on the New York Canada border is another example of differential border is another example of differential erosion. The water going over the falls erodes erosion. The water going over the falls erodes the edge of the thick, soft shale layer under the edge of the thick, soft shale layer under a hard limestone layer. This undercuts the a hard limestone layer. This undercuts the limestone, causing it to give way. This photo limestone, causing it to give way. This photo of the American Falls, one part of Niagara of the American Falls, one part of Niagara Falls, shows huge limestone boulders that Falls, shows huge limestone boulders that have fallen. For the past 10,000 years, the have fallen. For the past 10,000 years, the falls have continued to move upstream, falls have continued to move upstream, eroding the rock at the higher part of the eroding the rock at the higher part of the river, at an average rate of about 1 meter (m) river, at an average rate of about 1 meter (m) a year. a year. The surrounding sedimentary rocks have eroded away to expose the resistant igneous rock that forms Devils Tower in Wyoming. The surrounding sedimentary rocks have eroded away to expose the resistant igneous rock that forms Devils Tower in Wyoming. Differential Erosion Differential Erosion Some of the most dramatic scenery in Some of the most dramatic scenery in the world occurs where soft rock erodes the world occurs where soft rock erodes more quickly than harder rock. You saw more quickly than harder rock. You saw differential erosion in action when differential erosion in action when you watched the multimedia stream tables you watched the multimedia stream tables that had a layer of clay between two layers that had a layer of clay between two layers of sand. The water easily eroded away the top layer of sand, but the clay layer resisted The Niagara River tumbles over a hard layer of limestone to form a fall 50 m high. erosion. As long as the clay layer was intact, the bottom layer of sand was protected. This is called differential erosion, because the layers erode at different rates. Differential erosion happens any time soft rock is eroded away, leaving harder rock of sand. The water easily eroded away the top layer of sand, but the clay layer resisted The Niagara River tumbles over a hard layer of limestone to form a fall 50 m high. erosion. As long as the clay layer was intact, Wind Erosion and Rain Forests How could erosion in Africa help the Amazon rain forests, all the way across the Atlantic Ocean? Windstorms on the Sahara desert carry dust high into the atmosphere. 20 the bottom layer of sand was protected. This is called differential erosion, because the layers erode at different rates. Differential erosion happens any time soft rock is eroded away, leaving harder rock Wind Erosion and Rain Forests How could erosion in Africa help the Amazon rain forests, all the way across the Atlantic Ocean? Windstorms on the Sahara desert carry dust high into the atmosphere. 20 Investigation 2: Weathering and Erosion No. 18 Notebook Master Investigation 2: Weathering and Erosion No. 18 Notebook Master

19 This large mushroom rock near Lees Ferry on the Colorado River in Arizona is the result of differential erosion. Warning: Rock structures of this kind can be hazardous. Be careful around them. Massive dust storms can carry dust across the ocean. was created by weathering and erosion. All of these scenic wonders were once solid rock. Weathering and erosion produce sediments This large mushroom rock near Lees Ferry on the Colorado River in Arizona is the result of differential erosion. Warning: Rock structures of this kind can be hazardous. Be careful around them. that can form new rocks, create soil, change Massive dust storms can carry dust across the ocean. was created by weathering and erosion. All of these scenic wonders were once solid rock. Weathering and erosion produce sediments that can form new rocks, create soil, change High-altitude winds carry the dust west across landforms, and even affect air quality. Think High-altitude winds carry the dust west across landforms, and even affect air quality. Think the Atlantic Ocean, and sometimes to the about that the next time you feel smooth, the Atlantic Ocean, and sometimes to the about that the next time you feel smooth, rain forests of South and Central America. rounded sand between your toes at the beach, rain forests of South and Central America. rounded sand between your toes at the beach, The soil in rain forests is normally of poor see a crack in a rock or a sidewalk, or eat a The soil in rain forests is normally of poor see a crack in a rock or a sidewalk, or eat a quality, but the dust from Africa provides piece of fruit! quality, but the dust from Africa provides piece of fruit! many of the nutrients that the rain forest plants need to survive. There is also a negative side to all this dust. Some of the dust settles on coral reefs in many of the nutrients that the rain forest Think Questions plants need to survive. 1. Choose one of the photos of rock Some of the dust settles on coral reefs in There is also a negative side to all this dust. Think Questions 1. Choose one of the photos of rock the sea. The dust carries bacteria and fungi formations in this article. Make a the sea. The dust carries bacteria and fungi formations in this article. Make a that can kill or weaken the coral. When sketch of the formation. Label which that can kill or weaken the coral. When sketch of the formation. Label which the dust settles over populated areas, it can layers you think might be hard rock the dust settles over populated areas, it can layers you think might be hard rock trigger asthma and other respiratory diseases. and which might be softer. What is trigger asthma and other respiratory diseases. and which might be softer. What is Other places in the world are affected by your evidence? Other places in the world are affected by your evidence? dust sources other than the Sahara Desert. 2. Describe the processes you think might dust sources other than the Sahara Desert. 2. Describe the processes you think might Consider this dust from China sometimes have produced the mushroom-shaped Consider this dust from China sometimes have produced the mushroom-shaped reaches people living in California! rock in the photo above. reaches people living in California! rock in the photo above. Weathering and erosion created the Grand Canyon and many spectacular landforms around the world. The spires and hoodoos of Bryce Canyon in Utah, the rugged Badlands in South Dakota, and the rounded Blue Ridge Mountains extending from West Virginia to Pennsylvania are all products of weathering and erosion. Even Mammoth Cave in Kentucky, the world s longest cave system, 3. Think about your community. Give at least one example of where you have seen: Weathering Erosion Differential erosion A landform created by weathering and erosion Weathering and erosion created the Grand Canyon and many spectacular landforms around the world. The spires and hoodoos of Bryce Canyon in Utah, the rugged Badlands in South Dakota, and the rounded Blue Ridge Mountains extending from West Virginia to Pennsylvania are all products of weathering and erosion. Even Mammoth Cave in Kentucky, the world s longest cave system, Investigation 2: Weathering and Erosion 21 Investigation 2: Weathering and Erosion No. 19 Notebook Master 3. Think about your community. Give at least one example of where you have seen: Weathering Erosion Differential erosion A landform created by weathering and erosion Investigation 2: Weathering and Erosion 21 Investigation 2: Weathering and Erosion No. 19 Notebook Master

20 Response Sheet Investigation 2 Response Sheet Investigation 2 Two students were at the beach. The first student said, Two students were at the beach. The first student said, Look at all this sand! I wonder where it came from. Look at all this sand! I wonder where it came from. The second student replied, The second student replied, Sand comes from rocks, and rocks come from mountains, but I don t see any around here. Sand comes from rocks, and rocks come from mountains, but I don t see any around here. If you were at the beach, what would you say to the students to help them think about the sand on the beach? If you were at the beach, what would you say to the students to help them think about the sand on the beach? Investigation 2: Weathering and Erosion No. 20 Notebook Master Investigation 2: Weathering and Erosion No. 20 Notebook Master

21 Seawater Investigation Seawater Investigation Materials 1 Plastic cup with lid 60 ml Limewater (calcium hydroxide solution) 4 Straws with hole punched in side Safety goggles Materials 1 Plastic cup with lid 60 ml Limewater (calcium hydroxide solution) 4 Straws with hole punched in side Safety goggles Instructions 1. Work with your group. Measure 60 ml of limewater into a cup. Limewater is a Ca(OH)2 solution. 2. Place the lid on the cup. 3. Use the table below to record observations before bubbling. 4. Take turns poking your straw through the hole in the lid and gently blowing air into the limewater. Continue taking turns for 2 or 3 minutes. SAFETY NOTE: Don t suck up the limewater. Make sure you don t blow so hard that the water splatters. If you get some limewater on your hands, rinse them with clear water. 5. Record observations after bubbling. 6. Let the cup stand for 5 minutes and then record your observations. Instructions 1. Work with your group. Measure 60 ml of limewater into a cup. Limewater is a Ca(OH)2 solution. 2. Place the lid on the cup. 3. Use the table below to record observations before bubbling. 4. Take turns poking your straw through the hole in the lid and gently blowing air into the limewater. Continue taking turns for 2 or 3 minutes. SAFETY NOTE: Don t suck up the limewater. Make sure you don t blow so hard that the water splatters. If you get some limewater on your hands, rinse them with clear water. 5. Record observations after bubbling. 6. Let the cup stand for 5 minutes and then record your observations. Seawater Observations Seawater Observations Observations of Ca(OH)2 cup before bubbling Observations of Ca(OH)2 cup after bubbling Observations of Ca(OH)2 cup after standing for 5 minutes Observations of Ca(OH)2 cup before bubbling Observations of Ca(OH)2 cup after bubbling Observations of Ca(OH)2 cup after standing for 5 minutes Analysis: What do you think the limewater reaction has to do with limestone formation? Analysis: What do you think the limewater reaction has to do with limestone formation? Investigation 3: Deposition No. 21 Notebook Master Investigation 3: Deposition No. 21 Notebook Master

22 Basin Questions Basin Questions Use the correlation of Grand Canyon rocks from Investigation 1 to help answer these questions. Use the correlation of Grand Canyon rocks from Investigation 1 to help answer these questions. 1. Which Grand Canyon rock layer is the oldest that we have observed so far? 1. Which Grand Canyon rock layer is the oldest that we have observed so far? 2. How do you know it is the oldest? 2. How do you know it is the oldest? 3. Which layer in the Grand Canyon is the youngest that we have observed so far? 3. Which layer in the Grand Canyon is the youngest that we have observed so far? 4. How do you know it is the youngest? 4. How do you know it is the youngest? 5. What do you think is below the oldest layer? 5. What do you think is below the oldest layer? Investigation 3: Deposition No. 22 Notebook Master Investigation 3: Deposition No. 22 Notebook Master

23 Response Sheet Investigation 4 Response Sheet Investigation 4 A student s little brother said to her, A student s little brother said to her, The fossils in the Grand Canyon are dead bodies of animals that washed up onto the rocks as the river passed by. The fossils in the Grand Canyon are dead bodies of animals that washed up onto the rocks as the river passed by. If you were the student, what would you say to your brother? If you were the student, what would you say to your brother? Investigation 4: Fossils and Past Environments No. 23 Notebook Master Investigation 4: Fossils and Past Environments No. 23 Notebook Master

24 Grand Canyon Environments Rock layer Kaibab Formation Rock evidence Mostly limestone containing some grains of sand. Toroweap Mostly limestone with Formation some sandstone and siltstone layers. Coconino with broken rock fragments. Wellsorted sand grains are mostly the same size. Large crossbeds. Hermit Shale Shaley siltstone in many areas. Raindrop imprints and mud cracks. Supai Group Red and tan sandstones, siltstones, and a few limestones. Redwall Thick gray limestone stained red from iron oxide (rust). Muav Shaley, yellowish gray limestone. Fossil evidence Sponges, corals, brachiopods, clams, and snails. Sponges, corals, brachiopods, clams, snails, and crinoids. Reptile and insect tracks. Plant fossils, including aridclimate ferns and conifers, insects, worm trails, reptile or amphibian tracks. Vertebrate tracks in the sandstone layers, some brachiopods in the limestone layers. Fossils few and far between. Brachiopods, corals, crinoids, and bryozoans common. Most fossils whole, but much limestone made of fragments of fossilized shells. Trilobites, brachiopods. Investigation 4: Fossils and Past Environments No. 24 Notebook Master Grand Canyon Environments Rock layer Kaibab Formation Rock evidence Mostly limestone containing some grains of sand. Toroweap Mostly limestone with Formation some sandstone and siltstone layers. Coconino with broken rock fragments. Wellsorted sand grains are mostly the same size. Large crossbeds. Hermit Shale Shaley siltstone in many areas. Raindrop imprints and mud cracks. Supai Group Red and tan sandstones, siltstones, and a few limestones. Redwall Thick gray limestone stained red from iron oxide (rust). Muav Shaley, yellowish gray limestone. Fossil evidence Sponges, corals, brachiopods, clams, and snails. Sponges, corals, brachiopods, clams, snails, and crinoids. Reptile and insect tracks. Plant fossils, including aridclimate ferns and conifers, insects, worm trails, reptile or amphibian tracks. Vertebrate tracks in the sandstone layers, some brachiopods in the limestone layers. Fossils few and far between. Brachiopods, corals, crinoids, and bryozoans common. Most fossils whole, but much limestone made of fragments of fossilized shells. Trilobites, brachiopods. Investigation 4: Fossils and Past Environments No. 24 Notebook Master

25 Time-Line Calculations Time-Line Calculations Era Period Cenozoic (Today) Quaternary Age (years) 0.00 Triassic Paleozoic Permian Pennsylvanian Mississippian Devonian Silurian Ordovician Cambrian Precambrian Period Cenozoic (Today) Quaternary Mesozoic 144,000,000 1,600,000 66,000,000 Cretaceous 144,000, ,000,000 Triassic 245,000,000 Paleozoic 286,000, ,000,000 Permian 286,000,000 Pennsylvanian 320,000, ,000,000 Mississippian 360,000, ,000,000 Devonian 408,000, ,000,000 Silurian 438,000, ,000,000 Ordovician 505,000, ,000,000 Cambrian 570,000,000 Distance on Distance on time line time line (mm) (cm) 0.00 Jurassic 208,000, ,000,000 Precambrian 4,600,000,000 4,600,000,000 1 mm = 1,000,000 years 1 mm = 1,000,000 years Age (years) Tertiary 66,000,000 Cretaceous Jurassic Era 1,600,000 Tertiary Mesozoic Distance on Distance on time line time line (mm) (cm) Investigation 4: Fossils and Past Environments No. 25 Notebook Master Investigation 4: Fossils and Past Environments No. 25 Notebook Master

26 Time-Line Instructions Time-Line Instructions 1. Label one end of the adding-machine tape 0 = Now. 1. Label one end of the adding-machine tape 0 = Now. 2. Draw a line across the tape to mark the start of the Quaternary period, which began 1,600,000 years ago. Remember, 1 mm on the adding-machine tape equals 1 million years of earth history. The beginning of the Quaternary is 1.6 mm back from now. Not very far! 2. Draw a line across the tape to mark the start of the Quaternary period, which began 1,600,000 years ago. Remember, 1 mm on the adding-machine tape equals 1 million years of earth history. The beginning of the Quaternary is 1.6 mm back from now. Not very far! 3. Locate the beginning of the Tertiary period. Divide 66,000,000 years by 1,000,000 years per millimeter to get 66 mm. 66 mm = 6.6 cm. Measure back 6.6 cm from zero and mark the beginning of the Tertiary period. The distance between 6.6 cm (the beginning of the Tertiary period) and the start of the Quaternary period (also the end of the Tertiary period) represents the entire Tertiary period. 3. Locate the beginning of the Tertiary period. Divide 66,000,000 years by 1,000,000 years per millimeter to get 66 mm. 66 mm = 6.6 cm. Measure back 6.6 cm from zero and mark the beginning of the Tertiary period. The distance between 6.6 cm (the beginning of the Tertiary period) and the start of the Quaternary period (also the end of the Tertiary period) represents the entire Tertiary period. 4. Continue in the same manner for the rest of the time line. 4. Continue in the same manner for the rest of the time line. 5. Draw an extra-heavy line marking the beginning of each era. 5. Draw an extra-heavy line marking the beginning of each era. Investigation 4: Fossils and Past Environments No. 26 Notebook Master Investigation 4: Fossils and Past Environments No. 26 Notebook Master

27 Shale, limestone, sandstone Z2 Z1 Investigation 4: Fossils and Past Environments No. 27 Notebook Master Shale, sandstone, limestone Shale, conglomerate B4 B3 B2 B1 Shale, sandstone Shale, conglomerate Shale, limestone, sandstone Z6 Z5 Z4 Z3 Z2 Z1 Shale, sandstone Shale, sandstone, limestone Shale, conglomerate B4 B3 B2 B1 Shale Shale Coal, sandstone Shale, sandstone, limestone Z7 B7 B6 B5 B8 B9 Shale, sandstone Shale B7 B6 B5 Shale Shale, conglomerate Z3 B8 Z4 Coal, sandstone Shale, sandstone Z5 B9 Shale, sandstone, limestone Z6 Z7 Metamorphic and igneous rocks, no fossils Vishnu, etc. Metamorphic and igneous rocks, no fossils Vishnu, etc. B = Bryce Canyon Z = Zion National Park Shale Bright Angel Tapeats, siltstone, shale, dolomite Muav Temple Butte Redwall Supai Shale Hermit, sandstone Toroweap Coconino, sandstone Kaibab B = Bryce Canyon Z = Zion National Park Shale Bright Angel Tapeats, siltstone, shale, dolomite Muav Temple Butte Redwall Supai Shale Hermit, sandstone Toroweap Coconino, sandstone Kaibab Index-Fossil Correlations Index-Fossil Correlations Investigation 4: Fossils and Past Environments No. 27 Notebook Master

28 Index-Fossil Correlation Questions Index-Fossil Correlation Questions Answer these questions after you have identified and correlated the rock layers at the three parks. Answer these questions after you have identified and correlated the rock layers at the three parks. 1. Were any layers at all three canyons the same age? 1. Were any layers at all three canyons the same age? 2. Which rock layers contained the same index fossils at Zion and the Grand Canyon? 2. Which rock layers contained the same index fossils at Zion and the Grand Canyon? 3. Which rock layers contained the same index fossils at Zion and Bryce? 3. Which rock layers contained the same index fossils at Zion and Bryce? 4. Which rock layers contained the same index fossils at the Grand Canyon and Bryce? 4. Which rock layers contained the same index fossils at the Grand Canyon and Bryce? 5. Which canyon has the oldest rocks? 5. Which canyon has the oldest rocks? 6. What was the age of the oldest rock layer? 6. What was the age of the oldest rock layer? 7. Which canyon has the youngest rocks? 7. Which canyon has the youngest rocks? 8. What was the age of the youngest rock layer? 8. What was the age of the youngest rock layer? 9. Is rock layer B3 at Bryce older or younger than the Supai Group at the Grand Canyon? How do you know? 9. Is rock layer B3 at Bryce older or younger than the Supai Group at the Grand Canyon? How do you know? 10. Is rock layer B2 at Bryce older or younger than rock layer Z1 at Zion? How do you know? 10. Is rock layer B2 at Bryce older or younger than rock layer Z1 at Zion? How do you know? Investigation 4: Fossils and Past Environments No. 28 Notebook Master Investigation 4: Fossils and Past Environments No. 28 Notebook Master

29 Rocks over Time Rocks over Time Rock Layer Kaibab Formation Toroweap Formation Coconino Hermit Shale Supai Group Redwall Time of deposition (approximately) Ended 255,000,000 years ago Began 260,000,000 years ago Ended 260,000,000 years ago Began 265,000,000 years ago Ended 265,000,000 years ago Began 270,000,000 years ago Ended 270,000,000 years ago Began 275,000,000 years ago Ended 275,000,000 years ago Began 325,000,000 years ago Ended 325,000,000 years ago Began 360,000,000 years ago Temple Butte Ended 370,000,000 years ago Began 375,000,000 years ago Muav Bright Angel Shale Tapeats Ended 525,000,000 years ago Began 530,000,000 years ago Ended 530,000,000 years ago Began 540,000,000 years ago Ended 540,000,000 years ago Began 545,000,000 years ago Distance on time line Period 25.5 cm 26.0 cm Kaibab Formation 26.0 cm 26.5 cm Toroweap Formation 26.5 cm 27.0 cm Coconino 27.0 cm 27.5 cm Hermit Shale 27.5 cm 32.5 cm Supai Group 32.5 cm 36.0 cm Redwall 37.0 cm 37.5 cm Time of deposition (approximately) Ended 255,000,000 years ago Began 260,000,000 years ago Ended 260,000,000 years ago Began 265,000,000 years ago Ended 265,000,000 years ago Began 270,000,000 years ago Ended 270,000,000 years ago Began 275,000,000 years ago Ended 275,000,000 years ago Began 325,000,000 years ago Ended 325,000,000 years ago Began 360,000,000 years ago Temple Butte Ended 370,000,000 years ago Began 375,000,000 years ago 52.5 cm 53.0 cm Muav 53.0 cm 54.0 cm Bright Angel Shale 54.0 cm 54.5 cm Tapeats Ended 525,000,000 years ago Began 530,000,000 years ago Ended 530,000,000 years ago Began 540,000,000 years ago Ended 540,000,000 years ago Began 545,000,000 years ago Period 25.5 cm 26.0 cm 26.0 cm 26.5 cm 26.5 cm 27.0 cm 27.0 cm 27.5 cm 27.5 cm 32.5 cm 32.5 cm 36.0 cm 37.0 cm 37.5 cm 52.5 cm 53.0 cm 53.0 cm 54.0 cm 54.0 cm 54.5 cm 1 cm = 10,000,000 years 1 cm = 10,000,000 years Rock Layer Distance on time line Investigation 4: Fossils and Past Environments No. 29 Notebook Master Investigation 4: Fossils and Past Environments No. 29 Notebook Master

30 Cooling-Rate Investigation Cooling-Rate Investigation What effect does cooling rate have on crystal formation? What effect does cooling rate have on crystal formation? 1. Hypothesis: How do you think cooling rate will affect crystal formation? 1. Hypothesis: How do you think cooling rate will affect crystal formation? 2. What materials will you need for your investigation? 2. What materials will you need for your investigation? 3. Describe your procedure. 3. Describe your procedure. 4. Record data and/or describe your results. 4. Record data and/or describe your results. 5. What conclusions can you draw about crystals in igneous rocks? 5. What conclusions can you draw about crystals in igneous rocks? Investigation 5: Igneous Rocks No. 30 Notebook Master Investigation 5: Igneous Rocks No. 30 Notebook Master

31 Igneous Rock Observations Rock Description Igneous Rock Observations Intrusive or extrusive? Identification Rock Investigation 5: Igneous Rocks No. 31 Notebook Master Description Intrusive or extrusive? Identification Investigation 5: Igneous Rocks No. 31 Notebook Master

32 Rock-Layer Age Puzzle Rock-Layer Age Puzzle This illustration shows a rock column. Using potassium-argon dating, geologists have calculated an age of 200 million years for rock A, a granite. Rock F, the volcano, has been given an age of 225,000 years. Use the ages and illustration to answer the questions. This illustration shows a rock column. Using potassium-argon dating, geologists have calculated an age of 200 million years for rock A, a granite. Rock F, the volcano, has been given an age of 225,000 years. Use the ages and illustration to answer the questions. F Volcano Ba sa D C ike Canyon Shale E lt d lt d ike Shale E Volcano D sa Canyon Ba F B C B A 1. Which rock (A, B, C, D, E, or F) is the oldest? How do you know? A 1. Which rock (A, B, C, D, E, or F) is the oldest? How do you know? 2. Which rock (A, B, C, D, E, or F) is the youngest? How do you know? 2. Which rock (A, B, C, D, E, or F) is the youngest? How do you know? 3. Did the canyon form before or after layers B, C, D, and E? How do you know? 3. Did the canyon form before or after layers B, C, D, and E? How do you know? 4. Did rock B form before or after rock C? How do you know? 4. Did rock B form before or after rock C? How do you know? 5. When did rocks B, C, D, and E form? Give a range, between XXX and XXX. How do you know? 5. When did rocks B, C, D, and E form? Give a range, between XXX and XXX. How do you know? 6. Which rock layers are sedimentary rocks? Which are igneous rocks? 6. Which rock layers are sedimentary rocks? Which are igneous rocks? Granite Investigation 5: Igneous Rocks No. 32 Notebook Master Granite Investigation 5: Igneous Rocks No. 32 Notebook Master

33 Wegener Video Questions Wegener Video Questions 1. What evidence did Wegener use to support his idea of continental drift? 1. What evidence did Wegener use to support his idea of continental drift? 2. What did other scientists say about Wegener s ideas? 2. What did other scientists say about Wegener s ideas? 3. How did other scientists explain why the continents seemed to fit together? 3. How did other scientists explain why the continents seemed to fit together? Investigation 6: Volcanoes and Earthquakes No. 33 Notebook Master Investigation 6: Volcanoes and Earthquakes No. 33 Notebook Master

34 Iron, nickel Layer Earth s Layers Information Igneous rocks like granite, sedimentary rocks, other rocks More iron and magnesium than the crust; less silicon and aluminum More iron, magnesium, and calcium than the crust Iron, nickel Iron, nickel From ocean temperature to 870 C near the mantle boundary From air temperature to 870 C near the mantle boundary 500 C to 900 C 5 km to 8 km Less dense than 30 to the oceanic 60 km crust More dense than crust and asthenosphere 500 C near More dense crust to 4000 C than crust, less near core dense than solid upper mantle 4400 C to More dense 6100 C than the mantle 7000 C Most dense layer Consistency Composition Temperature Basalt More dense than the continental crust Density More dense than the continental crust km 2900 km 2200 km 1250 km in diameter Thickness 5 km to 8 km Less dense than 30 to the oceanic 60 km crust More dense than crust and asthenosphere 500 C near More dense crust to 4000 C than crust, less near core dense than solid upper mantle 4400 C to More dense 6100 C than the mantle 7000 C Most dense layer Investigation 6: Volcanoes and Earthquakes No. 34 Notebook Master Earth s Layers Information Igneous rocks like granite, sedimentary rocks, other rocks More iron and magnesium than the crust; less silicon and aluminum More iron, magnesium, and calcium than the crust Iron, nickel From ocean temperature to 870 C near the mantle boundary From air temperature to 870 C near the mantle boundary 500 C to 900 C Thickness Basalt Density Investigation 6: Volcanoes and Earthquakes No. 34 Notebook Master Consistency Composition Temperature km 2900 km 2200 km 1250 km in diameter Layer

35 World maps in the late 1500s began to give a more complete view of Earth. Some people began to wonder if South America and Africa were once connected. World maps in the late 1500s began to give a more complete view of Earth. Some people began to wonder if South America and Africa were once connected. The Human Story of the Theory of Plate Tectonics The Human Story of the Theory of Plate Tectonics The theory of plate tectonics is one of have happened was unknown. It would take The theory of plate tectonics is one of have happened was unknown. It would take the most important scientific developments 300 years before scientists came up with some the most important scientific developments 300 years before scientists came up with some in modern times. But the idea that Earth s ideas for how continents could move. in modern times. But the idea that Earth s ideas for how continents could move. outer layer is made of moving plates was not widely accepted until the 1960s. It s very likely that the idea was not included outer layer is made of moving plates was A Geology Puzzle Think about a time before satellite photos not widely accepted until the 1960s. It s very likely that the idea was not included A Geology Puzzle Think about a time before satellite photos in your grandparents science textbooks. It of Earth, before seafloor maps, and even in your grandparents science textbooks. It of Earth, before seafloor maps, and even took several centuries of gathering data and before accurate global land maps. As explorers took several centuries of gathering data and before accurate global land maps. As explorers sharing ideas before the scientific community during the 15th and 16th centuries traveled sharing ideas before the scientific community during the 15th and 16th centuries traveled accepted the evidence. to the far reaches of the planet, they asked: accepted the evidence. to the far reaches of the planet, they asked: The origins of the theory go back to the How did fossils of creatures that lived in the The origins of the theory go back to the How did fossils of creatures that lived in the first world maps in the late 1500s. These ocean get on top of enormous mountains? Is first world maps in the late 1500s. These ocean get on top of enormous mountains? Is maps included most of Earth. After viewing there a relationship between volcanoes and maps included most of Earth. After viewing there a relationship between volcanoes and the shapes of Africa and South America, some earthquakes? Is it possible that the continents the shapes of Africa and South America, some earthquakes? Is it possible that the continents people began to wonder if they were once were close together at one time, making one people began to wonder if they were once were close together at one time, making one connected. It certainly seemed likely that the big landform? connected. It certainly seemed likely that the big landform? continents were once joined, but how it could continents were once joined, but how it could Investigation 6: Volcanoes and Earthquakes No. 35 Notebook Master Investigation 6: Volcanoes and Earthquakes No. 35 Notebook Master

36 Explaining the Puzzle There were two main explanations for the mountaintop marine fossils. Some believed Putting the Puzzle Pieces Together The puzzle-like Explaining the Puzzle There were two main explanations for the mountaintop marine fossils. Some believed Putting the Puzzle Pieces Together The puzzle-like that the land had not changed since the shapes of the continents that the land had not changed since the shapes of the continents beginning of time, but that global flooding intrigued Alfred Wegener beginning of time, but that global flooding intrigued Alfred Wegener raised the sea level above the highest peaks of ( ), a German raised the sea level above the highest peaks of ( ), a German the world. Others observed earthquake and meteorologist. He was also the world. Others observed earthquake and meteorologist. He was also volcanic activity and reasoned that processes interested in the odd fossil connections that volcanic activity and reasoned that processes interested in the odd fossil connections that inside Earth changed the surface, creating he and others discovered. For example, he inside Earth changed the surface, creating he and others discovered. For example, he new hills and mountains. found fossils of animals that once lived in new hills and mountains. found fossils of animals that once lived in James Hutton ( ), tropical climates in areas that are now cold James Hutton ( ), tropical climates in areas that are now cold a Scottish geologist, climates. He observed that fossils of the same a Scottish geologist, climates. He observed that fossils of the same supported this second plants and animals that lived during the supported this second plants and animals that lived during the explanation. He observed same geological period were now in rocks explanation. He observed same geological period were now in rocks that streams carried on different sides of the ocean. The fossils that streams carried on different sides of the ocean. The fossils sediments away from his included a unique reptile called Cynognathus sediments away from his included a unique reptile called Cynognathus farm. He decided that there in South America and Australia; a freshwater farm. He decided that there in South America and Australia; a freshwater must be forces lifting sections reptile called Mesosaurus, which was similar must be forces lifting sections reptile called Mesosaurus, which was similar of Earth s surface to balance out erosion. to a small crocodile found in Brazil and South of Earth s surface to balance out erosion. to a small crocodile found in Brazil and South If there weren t lifting forces, he reasoned, Africa; and a land reptile, Lystrosaurus, from If there weren t lifting forces, he reasoned, Africa; and a land reptile, Lystrosaurus, from erosion would have smoothed the world rocks of the same age in South America, erosion would have smoothed the world rocks of the same age in South America, into a perfectly round sphere. His theory Africa, and Antarctica. into a perfectly round sphere. His theory Africa, and Antarctica. required large amounts of heat energy from Can you imagine an entire community required large amounts of heat energy from Can you imagine an entire community inside Earth and extremely long periods of of animals like reptiles traveling from inside Earth and extremely long periods of of animals like reptiles traveling from time. These were groundbreaking ideas that Australia to South America? Neither could time. These were groundbreaking ideas that Australia to South America? Neither could could have revolutionized the thinking about Wegener. Instead he proposed a world where could have revolutionized the thinking about Wegener. Instead he proposed a world where Earth s history. But Hutton was unfortunately all the continents were connected as one Earth s history. But Hutton was unfortunately all the continents were connected as one a poor writer. Even the brightest scientific megacontinent he called Pangaea. He wrote a poor writer. Even the brightest scientific megacontinent he called Pangaea. He wrote minds could not understand his written of this megacontinent as a land where flora minds could not understand his written of this megacontinent as a land where flora explanations. Hutton s ideas might have been and fauna were able to mingle together before explanations. Hutton s ideas might have been and fauna were able to mingle together before lost to the world entirely if a close friend had they were split apart. In the early 1900s, he lost to the world entirely if a close friend had they were split apart. In the early 1900s, he not rewritten his book after his death. published his idea of drifting continents and not rewritten his book after his death. published his idea of drifting continents and The scientific community ultimately sparked a new way of viewing Earth s history. The scientific community ultimately sparked a new way of viewing Earth s history. accepted Hutton s ideas of a dynamic, But at the time, the scientific community accepted Hutton s ideas of a dynamic, But at the time, the scientific community vertically changing planet, but it was still a believed the continents were firmly anchored vertically changing planet, but it was still a believed the continents were firmly anchored long way from understanding evidence of in place. The continents might move up and long way from understanding evidence of in place. The continents might move up and continents fitting together. down, but they certainly did not drift around continents fitting together. down, but they certainly did not drift around the planet. the planet. Investigation 6: Volcanoes and Earthquakes 67 Investigation 6: Volcanoes and Earthquakes No. 36 Notebook Master Investigation 6: Volcanoes and Earthquakes 67 Investigation 6: Volcanoes and Earthquakes No. 36 Notebook Master

37 Resistance to Continental Drift Scientists dismissed Wegener s ideas as physically impossible. In truth, a weakness in Wegener s theory was that he wasn t able to explain what forces could move large masses of solid rock over such great distances. How could it have happened? What could move the continents? Wegener fought for the acceptance of his ideas of moving continents and a more dynamic planet until his untimely death in the Arctic region of Greenland in The scientific community dismissed the harder to ignore the fossil evidence surfacing across the world. To get around this problem, skeptical geologists imagined land bridges crisscrossing the ocean. When an ancient horse was found to have lived in France and Florida, a land bridge was drawn across the Atlantic Ocean. One of the most famous theories was the supposedly lost continent of Lemuria, which was hypothesized as an attempt to explain the scattered locations of the same rock formations and similar species of lemurs across the Indian Ocean. Of course, no evidence was found for most of these land bridges once technology allowed us to map the mysterious seafloor. Resistance to Continental Drift Scientists dismissed Wegener s ideas as physically impossible. In truth, a weakness in Wegener s theory was that he wasn t able to explain what forces could move large masses of solid rock over such great distances. How could it have happened? What could move the continents? Wegener fought for the acceptance of his ideas of moving continents and a more dynamic planet until his untimely death in the Arctic region of Greenland in The scientific community dismissed the harder to ignore the fossil evidence surfacing across the world. To get around this problem, skeptical geologists imagined land bridges crisscrossing the ocean. When an ancient horse was found to have lived in France and Florida, a land bridge was drawn across the Atlantic Ocean. One of the most famous theories was the supposedly lost continent of Lemuria, which was hypothesized as an attempt to explain the scattered locations of the same rock formations and similar species of lemurs across the Indian Ocean. Of course, no evidence was found for most of these land bridges once technology allowed us to map the mysterious seafloor. idea of moving continents, but it was much idea of moving continents, but it was much The colors on this map show the possible patterns of fossil distribution before the continents split apart. The colors on this map show the possible patterns of fossil distribution before the continents split apart Investigation 6: Volcanoes and Earthquakes No. 37 Notebook Master Investigation 6: Volcanoes and Earthquakes No. 37 Notebook Master

38 These diagrams show the break up of Pangaea and the spread of the continents to their current locations. The Missing Pieces: Mapping the Seafloor After Wegener s death, new information from the seafloor revived the debate about continental drift. Before the 19th century, most people thought the floor of the ocean was probably quite flat, although in the 16th century, some intrepid sailors took soundings of the seafloor, using long ropes called hand lines that they lowered to the ocean bottom. They found out that the seafloor was not as flat as people thought. Knowledge of the topography of the bottom of the ocean increased with the development of modern tools, starting in the 19th century. In 1853, US Navy lieutenant Matthew Maury ( ) published the first bathymetric (ocean-bottom) chart. It revealed the first evidence of underwater mountains in the central Atlantic Ocean (which Maury called Middle Ground ). Survey ships laying the trans-atlantic telegraph cable were able to confirm Maury s findings. These diagrams show the break up of Pangaea and the spread of the continents to their current locations. The Missing Pieces: Mapping the Seafloor After Wegener s death, new information from the seafloor revived the debate about continental drift. Before the 19th century, most people thought the floor of the ocean was probably quite flat, although in the 16th century, some intrepid sailors took soundings of the seafloor, using long ropes called hand lines that they lowered to the ocean bottom. They found out that the seafloor was not as flat as people thought. Investigation 6: Volcanoes and Earthquakes 69 Investigation 6: Volcanoes and Earthquakes No. 38 Notebook Master Knowledge of the topography of the bottom of the ocean increased with the development of modern tools, starting in the 19th century. In 1853, US Navy lieutenant Matthew Maury ( ) published the first bathymetric (ocean-bottom) chart. It revealed the first evidence of underwater mountains in the central Atlantic Ocean (which Maury called Middle Ground ). Survey ships laying the trans-atlantic telegraph cable were able to confirm Maury s findings. Investigation 6: Volcanoes and Earthquakes 69 Investigation 6: Volcanoes and Earthquakes No. 38 Notebook Master

39 measure the thickness of sediments, an measure the thickness of sediments, an important tool in the study of the seafloor. important tool in the study of the seafloor. In 1947, seismologists on the US research In 1947, seismologists on the US research ship Atlantis found that the sediment layer on ship Atlantis found that the sediment layer on the floor of the Atlantic was much thinner the floor of the Atlantic was much thinner than originally thought. Scientists had than originally thought. Scientists had believed that the ocean was at least 4 billion believed that the ocean was at least 4 billion years old. If it was that old, the sediment layer years old. If it was that old, the sediment layer on the ocean bottom should have become on the ocean bottom should have become very thick. But evidence from sonar readings very thick. But evidence from sonar readings showed that the sediments were relatively showed that the sediments were relatively thin. Why was that? thin. Why was that? Harry Hammond Harry Hammond Hess ( ), a Hess ( ), a professor of geology professor of geology at Princeton at Princeton University, would University, would finally offer finally offer key evidence of key evidence of seafloor spreading, seafloor spreading, which supported which supported Wegener s theory of Wegener s theory of drifting continents. During World War II drifting continents. During World War II ( ), Hess was captain of a transport ( ), Hess was captain of a transport ship equipped with the newest form of sonar, ship equipped with the newest form of sonar, used for navigating beach landings. Hess used for navigating beach landings. Hess decided to leave the equipment on to gather decided to leave the equipment on to gather data even during battles. He noticed that data even during battles. He noticed that the sediment layer was thinnest near the the sediment layer was thinnest near the mid-ocean ridge and got thicker as distance The first sonar systems were developed during World War I ( ) to help locate German U-boats. These systems could measure ocean depth by recording the time it took for a sound signal (usually an electrically generated ping) to travel from the ship to the seafloor and back again. The data collected from this early sonar confirmed the existence of the Mid-Atlantic Ridge. Sonar can also increased from the ridge. That meant that the sediments nearest the ridge had been deposited over less time. From this evidence, Hess and other scientists inferred that the crust nearer the ridge was younger. The evidence supported the idea that the Atlantic seafloor was spreading literally pushing Africa and South America apart (about 5 centimeters (cm) a year). 70 mid-ocean ridge and got thicker as distance The first sonar systems were developed during World War I ( ) to help locate German U-boats. These systems could measure ocean depth by recording the time it took for a sound signal (usually an electrically generated ping) to travel from the ship to the seafloor and back again. The data collected from this early sonar confirmed the existence of the Mid-Atlantic Ridge. Sonar can also increased from the ridge. That meant that the sediments nearest the ridge had been deposited over less time. From this evidence, Hess and other scientists inferred that the crust nearer the ridge was younger. The evidence supported the idea that the Atlantic seafloor was spreading literally pushing Africa and South America apart (about 5 centimeters (cm) a year). 70 Investigation 6: Volcanoes and Earthquakes No. 39 Notebook Master Investigation 6: Volcanoes and Earthquakes No. 39 Notebook Master

40 This map shows where earthquakes and volcanoes occur on Earth, just as you discovered in class. This map shows where earthquakes and volcanoes occur on Earth, just as you discovered in class. underwater mountains and combine them to defend and promote their ideas, which underwater mountains and combine them to defend and promote their ideas, which with earthquake and volcano data to study were different from the accepted scientific with earthquake and volcano data to study were different from the accepted scientific the processes that shape Earth. These data thinking of the day. Their new ideas changed the processes that shape Earth. These data thinking of the day. Their new ideas changed are evidence that Earth s crust is composed the way everyone would think about the are evidence that Earth s crust is composed the way everyone would think about the of solid tectonic plates floating on the planet we live on. of solid tectonic plates floating on the planet we live on. portion of the mantle that is fluid. This portion of the mantle that is fluid. This evidence strongly supports the modern theory of moving crustal plates, called plate tectonics. Looking back in history, we can now appreciate the courage and conviction it took for scientists like Wegener and Hess evidence strongly supports the modern Think Questions 1. What evidence caused Wegener to think the continents had been connected at one time? theory of moving crustal plates, called plate tectonics. Looking back in history, we can now appreciate the courage and conviction it took for scientists like Wegener and Hess 2. Why did most geologists disagree 1. What evidence caused Wegener to think the continents had been connected at one time? 2. Why did most geologists disagree with Wegener s ideas? with Wegener s ideas? 3. What are two pieces of evidence Think Questions 3. What are two pieces of evidence that scientists used to confirm the that scientists used to confirm the theory of plate tectonics, eventually theory of plate tectonics, eventually supporting Wegener s ideas? supporting Wegener s ideas? Investigation 6: Volcanoes and Earthquakes 71 Investigation 6: Volcanoes and Earthquakes 71 Investigation 6: Volcanoes and Earthquakes No. 40 Notebook Master Investigation 6: Volcanoes and Earthquakes No. 40 Notebook Master