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Shirley Duke Shirley Duke rourkeeducationalmedia.com Scan for Related Titles and Teacher Resources Level: S Word Count: 2,310 Words Before & After Reading Activities 100th word: tumble page 5 Before Reading: Building Academic Vocabulary and Background Knowledge Before reading a book, it is important to tap into what your child or students already know about the topic. This will help them develop their vocabulary, increase their reading comprehension, and make connections across the curriculum. 1. 2. 3. 4. 5. 6. 7. 8. Look at the cover of the book. What will this book be about? What do you already know about the topic? Let’s study the Table of Contents. What will you learn about in the book’s chapters? What would you like to learn about this topic? Do you think you might learn about it from this book? Why or why not? Use a reading journal to write about your knowledge of this topic. Record what you already know about the topic and what you hope to learn about the topic. Read the book. In your reading journal, record what you learned about the topic and your response to the book. After reading the book complete the activities below. Content Area Vocabulary Read the list. What do these words mean? biotic contour plowing drainage basin drought eons erosion faults geotextiles mass wasting minerals molten moraine rills sediment snout talus tsunamis watershed weathering After Reading: Comprehension and Extension Activity After reading the book, work on the following questions with your child or students in order to check their level of reading comprehension and content mastery. 1. 2. 3. 4. 5. What causes erosion? (Summarize) Why must farmers be knowledgeable in soil conservation methods? (Asking questions) What are some U.S. landforms that were created by erosion? (Text to self connection) What are some ways to prevent erosion? (Summarize) Name the three types of weathering and explain each. (Summarize) Extension Activity Collect several medium and small rocks from outside. Use rocks found in the grass or dirt rather than on the playground. Place the rocks in two small jars and fill each jar with water. Secure the lid on each jar. Shake only one jar about 100 times and leave the other jar alone. What do you notice? Write down what you see and any differences between the two jars. How can you describe the process of erosion from this activity? Table of Contents Ch 1 What Is Erosion? . . . . . . . . . . . . . . . . . . . . . . . 4 Ch 2 Weathering . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Ch 3 Erosion at Work . . . . . . . . . . . . . . . . . . . . . . . 18 Ch 4 Erosion’s Effect on Earth . . . . . . . . . . . . . . . . 26 Ch 5 People and Erosion . . . . . . . . . . . . . . . . . . . . 32 Ch 6 Battling Erosion . . . . . . . . . . . . . . . . . . . . . . 38 Modeling Chemical Erosion . . . . . . . . . . . . . . 45 Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 Websites to Visit . . . . . . . . . . . . . . . . . . . . . . 47 About the Author . . . . . . . . . . . . . . . . . . . . . . 48 C H A P T E R O N E What Is Erosion? If you visit any national park in the U.S. you could see great canyons, towering pinnacles, or a cave deep below the Earth’s surface. Many of these formations came from soil deposited in layers and cut through by water. Others formed as water, wind, and ice moved over or through rock, endlessly changing it. Moving water created the cliffs of Bryce Canyon and wore away the rock of Niagara Falls. Mammoth Cave grew as rainwater combined with carbon dioxide slowly dissolved the rock. 4 Mammoth Cave in Kentucky is a huge cave system with over 400 miles (644 kilometers) explored. Niagara Falls has eroded so much rock that the falls are now seven miles (11.2 kilometers) from their original location. After a flood, rapid changes become visible in the surrounding land. Soil and pebbles wash away and tumble along the river bottom. Mud deposits cover the topsoil. Erosion moves the materials that form the earth from one place to another. This process creates changes that shape the earth. 5 Rain and snow push loose rock and soil, or sediment, down a mountain or along a stream. Soil washes away. Gravity pulls tons of rocks and soil down a slope in a kind of erosion called mass wasting. When moving water or wind speed slows, the sediments drop. Soil deposits can build up land, like deltas and wetlands. Large rock piles from rockfalls create cone-shaped talus at mountain bases. 6 Heat from the core melts the rock in the middle layer, the mantle. This heat sets up currents that move the molten rock. The motion slowly moves the plates on top of the crust. The plate motions create disturbances in the crust. Crust Upper Mantle Lower Mantle Outer Core Inner Core 7 Some changes cause mountains to form and land to break apart. Different forces break apart rock. The rock bits crumble and are deposited on ocean floors in layers. Others slip beneath the crust. Moving water, wind, and ice then carry off the crumbling rock. The endless force of erosion continues as great mountains crumble and tons of sediments are carried away. Volcano Trench Magma Crust Mantle New rock forms when layers of sediment pile on the ocean floor and volcanoes hurl magma out to cool. The formation of the three groups of rock and their erosion make the rock cycle. 8 Earthquakes and Volcanoes Heavy ocean plates sink below the lighter continental plates. Their rocky layers melt into the mantle. The motion and the sinking crust causes earthquakes. Some rock is forced up, making mountain ranges. Land uplifts. Magma under pressure erupts, forming volcanoes. 9 C H A P T E R T W O Weathering Erosion carries away broken rocks and soil. But the action of breaking down rock is weathering. It happens in many ways. The weathered pieces stay where they are until moved by erosion. Mechanical weathering breaks rock through physical actions. The pieces are simply smaller. One of the main ways rock is weathered is by water freezing and thawing. Water Fills Crack Water Freezes to Ice Rock Breaks 10 Rocks are naturally full of holes and joints. When water freezes inside these holes, it can cause the rock to split. Rocks freeze in cold weather and expand as they heat up. Tiny cracks form in them. Water seeps in the cracks and freezes. Ice takes up more space than liquid water. The crack enlarges. The cycle repeats. Finally, pieces split and break off. During mechanical weathering, pieces of the rock are made smaller, but the chemical structure of the rock does not change. 11 Earthquakes split rock along fault lines. The open rock and soil is then exposed to further weathering. Salt water enters cracks and holes in ocean rocks and then evaporates. The salt remains. The salt build-up pushes on the 12 cracks and they split. Another type of weathering is chemical weathering, which breaks rock apart by causing changes in its make-up. In chemical weathering, water dissolves minerals of some rocks. A chemical change happens. The new forms are softer and weather more easily. When oxygen dissolves in water it can cause metallic minerals to rust. Carbon dioxide in rainwater forms a weak acid. Over time, the acid becomes strong enough to etch and eat away stone. Limestone is a soft rock that wears away easily. Weathering of limestone at Ernst Tinaja in Big Bend National Park created this formation. 13 Fast Fact: Bio- comes from the Greek word meaning life. The study of plants and animals is biology, and biotic weathering is caused by living things. Biotic, or organic, weathering happens when a living organism is the cause of weathering. Plant roots may enter a crack in a rock. The growing root presses against the surrounding rock. Roots are the cause of most biotic weathering. However, some plants also contain acids that wear away rock. Microscopic plants, like algae and fungi, may release acids as 14 they grow. This weakens and damages the rock. Over time, as weathering continues breaking them apart crumbling rocks become soil. Most weathering takes place at the surface, where rocks are exposed. However, faults and joints allow weathering deep into the rock. Burrowing animals like groundhogs or moles turn over soil when they dig. This can expose rock, which subjects it to weathering. Weathering breaks down rocks. They crumble in place and the pieces stay there until erosion moves them. 15 Caves Caves are natural openings in rock big enough for a person to go in. Caves are formed in different ways, but most come from rainwater mixing with carbon dioxide from the air. This makes a mild acid. The acid carried in the water moves down through the soil. The acids settle on the limestone or gypsum holding the water and dissolve the soft rock. Channels grow and widen. Caves take a few million years to form. Limestone Joints Waterfall Cavern Stalagmites Stalactites Pillar Water Table Stream As water seeps into the ground, caves and their features are formed one drip at a time. 16 Fast Fact: The 119 caves that make up Carlsbad Caverns formed when sulfuric acid seeped into the soil and slowly dissolved the limestone. 17 C H A P T E R T H R E E Erosion at Work Water plays an important part in weathering to break apart rocks into sediment. It is also the key agent for erosion. Water moves the sediments and deposits them in another place. Water’s movement through the water cycle powers erosion. Heat from the Sun evaporates water from the oceans. This turns the liquid into a gas, or water vapor. It rises into the air. The Water Cycle Snowmelt Runoff Precipitation Condensation Rain Runoff Evaporation Surface Flow Lake Groundwater Flow 18 Earth’s water cycle is always in motion. As it flows over land and evaporates from the surface, water plays a key role in erosion. Cooler temperatures high in the atmosphere cause water vapor to condense. It forms as droplets and makes clouds. The drops collect until they grow heavier than the air. The water falls as precipitation. Cool Air Precipitation 19 Land is made of high areas and low regions. Water falls on the landscape and runs downhill. It runs in small channels called rills and joins into a stream or river. This forms the drainage basin, or watershed. Falling rain soaks into the ground. Once soil is soaked, the drops slide. They carry the dust and soil particles that stick to them. 20 In streams and rivers, fast moving water pushes along bits of soil or rock. The moving water carries broken rock, picking up more as it churns across the riverbed. Tumbling rocks and sand rub against other rocks, breaking them into smaller pieces. Pieces rub and scrape the riverbed and loosen more rock. The friction rubs away sharp edges and points. 21 Falling water soaks the soil, making it heavier. Soil on slopes is constantly pulled down by gravity. Rills increase water’s flow down the slopes. Mass wasting moves large amounts of materials down the slopes in landslides and rock falls. Waves pound rocky shorelines and beaches. Wind and water currents flow over rock. Sand from beaches is washed away and deposited in other places. 22 Energy from the action of water, wind, and currents continually changes the shape of the coastline through coastal erosion. Between mountain peaks, snow builds up and the weight turns the snow to ice, forming glaciers. Gravity pushes heavy glacial ice downhill. The motion shoves rocks and soil downward, sculpting and scraping the land under it. When the glacier melts, a load of soil and rock remain. Melting water moves the sediment toward the ocean. Glaciers add tons of sediment to oceans each year. Glaciers reshape the land through erosion. Grooves gouged into boulders show the rubbing forces of the glacier material. 23 Blowing wind picks up bits of sand or dust. Wind easily erodes fine, loose soil. Soil loss limits the productiveness of the land. Bare ground is subject to more erosion. Sand and dust pollute the air. Sediment-filled winds scour rocks and cliff faces. The scrubbing action removes more sediment. Particles are carried as long as the wind blows. The sediments drop when the wind dies down, deposited wherever they land. Wind erosion is most common in flat, dry regions. 24 The Grand Canyon Rivers carve deep canyons as they run over plains. They cut through layers of soil and rock. Over thousands of years, they can expose the sides as canyon walls. The Colorado River has cut the Grand Canyon so deep that the average depth is one mile (1.6 kilometers). Different rock layers show the conditions at the time these rocks formed. The layers are visible in colorful bands. 25 C H A P T E R F O U R Erosion’s Effect on Earth Mountains, valleys, glaciers, and seas are landforms that have been shaped by erosion. These natural formations make up an area’s landscape. Many mountains may get their start as volcanoes. Others form when plates collide under the Earth’s crust and push it upward. Mountains form faster than erosion wears them down. However, weathering can change the shape of a mountain face over time as it is worn away through weathering and rock is carried away by erosion. Below the mountains are valleys. Rain and snow fall on the mountains. The water runs down the mountain slopes and into the valleys in rills and gullies. Those channels flow into rivers, which carry the water out to sea where they deposit sediments carried in the water. In this way, erosion moves sediments from high places to low. 26 The Appalachian Mountains are the oldest in North America. Their rounded tops show erosion’s work. The jagged peaks of the younger Teton Mountains show little erosion. 27 Glaciers scrape their way down mountain valleys, carving the ground below. They pile up rock and soil along their edges in their slow move downhill. Meltwater at their snout drops sediment called moraine. Recent, rapid melting of glaciers signals a changing climate. Studies show that more than 100,000 glaciers are shrinking rapidly. The Mendenhall Glacier in Alaska has retreated more than 9,000 feet (2,800 meters) since 1911. Landslides, flows, and creeps are a kind of erosion called mass wasting. Landslides happen fast and can move small amounts of sediments, or huge tons. Heavy rain increases the weight of the soil and the mass slips. When muddy sediments move it is called flow. Gravity pulls entire slopes downhill at a slow rate, known 28 as creep. Moving water filled with sediment carves deep, narrow valleys. The different sediment layers that have been deposited over eons line the canyon walls. Because different kinds of sediment make up each layer, the erosion rate of every layer varies. Flat-topped plateaus rise above the surrounding land. They form from lava flows, uplift, or erosion around softer rock below. Differing rates of erosion carve features in the rock. Hoodoos, the tall, thin spires of rock sticking up from an eroded region, look like stone statues. Crags and rock spires can be found in volcanic fields that first formed millions of years ago. The twisted shapes form in the eroded rock fields. Natural stone arches curve like rocky gates. They form when their softer rock center has eroded away. Similarly, buttes form when soft rock has eroded around harder rock. Buttes are isolated hills, smaller than a mesa, with steep sides. 29 Basins are low regions of the crust where sediments are deposited. Gentle slopes allow the materials to flow and collect. Young rivers flow rapidly in narrow channels. They widen and slow as they erode the rock around them. Older rivers start to wander in an S-shaped pattern. The Mississippi River runs from Minnesota to the Gulf of Mexico in the typical S-shaped curves. Rivers empty their sediments into large bodies of water at their mouths. The land that builds up around the river mouth is called a delta. New Orleans Mississippi River Gulf of Mexico Sediment carried by the Mississippi River built a large part of southern Louisiana. 30 The Continental Divide ins nta ou yM ock eR Th The Rocky Mountains form a natural boundary in North America. Water moves downhill, so water falling west of the mountains drains through channels to rivers that empty in the Pacific Ocean. Falling and running water east of the Rockies moves through the drainage basin system to the Atlantic Ocean or Gulf of Mexico.. 31 C H A P T E R F I V E People and Erosion Erosion is part of a natural process in the rock cycle. It breaks down rocks and deposits them as sediments. However, erosion can have a significant effect on people’s lives. At times, erosion can be costly, deadly, and harmful to the environment. Both drought and too much water can cause many erosionrelated problems. Flooding from heavy rains, hurricanes, or tsunamis carries mud, fertilizers, and toxic chemicals. This polluted water causes great damage to homes and businesses. 32 People may have to evacuate flooded areas and sometimes have to move entirely because their homes have been destroyed. Many small businesses don’t reopen after floods due to their losses. Businesses cannot operate when their suppliers cannot deliver goods. When businesses shut down, cities and towns suffer because they are not collecting as much tax money as they once were. 33 When areas flood, extra nutrients are often introduced into the water supply due to poor waste control. Runoff water with these nutrients enters lakes and ponds. Algal blooms overgrow in the water. Some algae produce harmful toxins. Removing them and treating the water can be costly for the community. Runoff water also dumps sediment into ponds and rivers. Too much sediment is harmful to the organisms living there. Common Sources of Erosion Pollutant Sources dirt, sand, grasses construction, stream banks, bare lawns, car washing nutrients over-fertilizing, pet waste, loose grass clippings and leaves germs garbage, pet waste carbon dioxide car exhaust, oil leaks, burning leaves and garbage pesticides overuse, applying before rains, spills metals 34 cars and trucks, metal gutters and downspouts Dry soil is easily picked up by the wind. Sandstorms are dangerous because they pollute the air and drastically reduce visibility on roads. Droughts cause problems, too. Without moisture, soil becomes dry and can be swept away by the wind. Sand and dust storms pollute the air. As sand blasts against buildings, it chips away at paint and clogs drains. The soil is stripped away, and dust coats the region. It settles over crops and roads. Trees and other plants are necessary to prevent erosion of soil. Wildfires strip the land of the grass and trees that hold the soil in place. Grazing animals, like sheep eat away at the ground’s plant cover and expose the soil. Clear-cutting forests acts much the same as a wildfire by leaving only bare soil, which erodes quickly. 35 Fossils from Erosion Erosion uncovered the first fossils. Sediments covered the ancient remains of some animals and plants. The layers of sediment preserved them while pressure built up and minerals replaced the hard parts. Eventually, water and wind moved across the long-ago resting sites to reveal fossils. In each layer, fossils reveal clues about the kind of life in the time when these ancient creatures lived. 36 Erosion of beaches is of great concern as well. Waves, tides, and currents remove sand from beaches. Many people build their homes along the coastline. But waves gradually pull away the land the homes are built on. When supporting land is removed, homes tumble into the oceans below. Loss of beauty and natural habitats are one part of erosion’s effect. The financial cost is enormous. Preventing erosion and repair after natural disasters is expensive and takes time. Due to beach erosion and dune destruction caused by Hurricane Sandy, in 2012, these oceanfront homes in New Jersey now sit on the water’s edge. 37 C H A P T E R S I X Battling Erosion Erosion affects people every day, often in a harmful way. Sometimes erosion can’t be controlled. Still, there are some things you can do to reduce its effects. Slow storm runoff in your yard. Learn how water flows on your lawn. Does it sink in or puddle? Sandy soil soaks up water, but denser materials, like clay, don’t absorb well. Add trees and shrubs to your lawn to prevent runoff. 38 Protect bare soil by planting grass or using mulch. Use materials that let water pass through them without getting too soggy. Instead of letting water from rain gutters flow into the lawn, use rain barrels to catch the water and use it to water your garden. 39 People may cover a seeded hillside with fabric to prevent erosion and allow new plants to grow and take root. The plants will then keep the soil in place. Construction sites use materials to prevent soil erosion. Nets, straw blankets, and woven geotextiles block runoff sediments. Certain farming practices limit erosion of topsoil. Contour plowing follows the lines of the land being plowed. The water makes tiny channels inside the rows of soil. This reduces the 40 amount of runoff water, and with it, soil loss. Farmers can hold soil during non-growing seasons by leaving leftover stalks in their fields. Groundcover along stream banks slows erosion. Grass, shrubs, and trees native to your area make good groundcover. Proper range management can prevent animals from overgrazing fields. On a larger scale, work to put an end to clearcutting forests. Good forest and land practices allow timber cutting with the least possible destruction to the environment. Forests are clear-cut to create farmland, harvest wood, and build structures. 41 Dams and levees control water flow near streams, rivers, and oceans. Naturally flowing water changes all the time. Too much water causes flooding, so gates on dams allow people to control the amount of water coming through. These structures remove water and prevent it from flooding the nearby land. Dams also generate electricity and supply cities with water. Fast Fact: Worldwide, there are 3,900 large dams used to block rivers. Almost every large river in the U.S. has a dam built on it. 42 Flooding during Hurricane Katrina in 2005 broke the levees and floodwalls protecting the city of New Orleans, causing incredible damage to homes and businesses. Dams and levees have problems, too. In some cases, flooding has been so severe that water broke them or went over the top. Dams that have given way flood the valleys below and cause great destruction. Sediments that support wetlands are reduced. Habitats are affected by the changes they cause. 43 Erosion Disasters Natural disasters like earthquakes cause erosion problems. Earthquakes are responsible for landslides, mudslides, and tsunamis. An earthquake caused a tsunami in Japan in 2011. Special construction practices and earthquake foundations reduce the damage earthquakes have on buildings. People can’t get rid of erosion, but they can reduce the erosion they cause. Anchor the soil in place with groundcover. Control the water moving over it by making changes. Be aware of good erosion control in your city. Learning about erosion and exploring changes in erosion prevention will keep the land as natural as possible. 44 Modeling Chemical Erosion Try this! 1. Think about what you’ve learned about erosion. 2. Fill 2 clear glasses with vinegar diluted with water to stand for acidic rainwater. 3. Add ¼ cup (50 milliliters) baking soda to one glass and a piece of chalk or limestone rock to the other and stir. 4. Make observations about what happens. 5. Observe the glasses the next day. Was anything different? 6. Explain the model in terms of chemical weathering. The acid and calcite in limestone rocks made a chemical change in the materials. This model shows the chemical change that takes place when slightly acidic rain dissolves limestone rock. 45 Glossary biotic (BYE-ah-tik): having to do with a living organism contour plowing (KAHN-toor PLOU-ing): to turn over the soil following the lines of the land to prevent erosion drainage basin (DRAY-nij BAY-suhn): an area of lower land that naturally collects runoff water and channels it to a river drought (drout): an extended time of little or no rain eons (EE-ahns): a period of time over thousands or millions of years erosion (i-ROH-zhuhn): the moving away of weathered rock by wind, water, and ice faults (FAWLTS): a large break in the surface of the earth geotextiles (jee-oh-TEK-STILZ): fabrics that allow water to filter through them as they protect, drain, or hold soil in place mass wasting (MAS WAYST-ing): a large amount of rock and soil moving down a slope rapidly through the force of gravity minerals (MIN-uhr-uhlz): a natural material with a crystal structure found in the earth that makes up rocks molten (MOHL-tuhn): the melted state of rock that makes up the mantle and can reach the earth’s surface moraine (MOE-rayn): rocks and sediment that are dropped at the end of a glacier when it melts rills (RILZ): small channels formed by runoff water as it moves downhill sediment (SED-uh-muhnt): rock, sand, or soil moved from one place to another by water, wind, or ice snout (SNOUT): the end region of a glacier, where it melts talus (TAL-us): large piles of rock at the base of a mountain resulting from rockfalls tsunamis (tse-NAH-mees): tall, damaging waves of water formed following an earthquake at sea watershed (WAW-tur-shed): the area of land that runoff water moves through to drain into a river weathering (WETH-uhr-ing): the breaking down of rock by physical, chemical, or biotic forces 46 Index basin(s) 20, 30, 31 canyons 4, 25 caves 16 drought(s) 32, 35 farming 40 flood(s) 5, 33, 34, 42, 43 fossils 36 glaciers 23, 24, 26, 28 ice 4, 8, 10, 11, 23 mass wasting 6, 22, 28 mountains 8, 26, 31 plants 14, 35, 36, 40 river(s) 5, 20, 21, 25, 26, 30, 31, 34, 42 sediment(s) 6, 8, 18, 24, 26, 28, 30, 32, 34, 36, 40, 43 weathering 10, 12, 13, 14, 18, 26 wind 4, 6, 8, 22, 24, 35, 36 Websites to Visit www.education.nationalgeographic.com/education/encyclopedia/ erosion/?ar_a=1 www.geography4kids.com/files/land_erosion.html www.ducksters.com/science/earth_science/erosion.php 47 About the Author Shirley Duke is a children’s author and a former science teacher. Most of her books are about science. She enjoys nature, being outdoors, and wildlife and spent time doing fieldwork when she studied earth science. She lives with her husband in Texas and in the Jemez Mountains of New Mexico, near a canyon and river valley eroded and cut long ago by the Jemez and San Antonio Rivers. Multi-colored layers of rock form the canyon walls and the red rock canyons make perfect hiking scenery. Meet The Author! www.meetREMauthors.com © 2015 Rourke Educational Media All rights reserved. No part of this book may be reproduced or utilized in any form or by any means, electronic or mechanical including photocopying, recording, or by any information storage and retrieval system without permission in writing from the publisher. www.rourkeeducationalmedia.com PHOTO CREDITS: Cover © Glowing Earth Photography; title page © FRANK FENNENA; page 3 © Serg Myshkovsky; page 4 © snikeltrut; page 5 © maryTR; page 6 © shkonst; page 7 © photoplotnikov; page 8 © Andrea Danti; page 9 © Popescu Lacob Emanuel; page 10 © domi8nic; page 11 © orxy; page 12 © Lee Prince; page 13 © Richard Stouffer; page 14 © Razvan; page 15 © Michael Sick; page 16 © Gary Hincks; page 17 © megaquib; page 18 © merkushev Vasiliy; page 19 © Kevinjeonoo; page 20 © Ravindra Joisa; page 21, 39 © Kodachrome25; page 22 © Eddie Khoriaty; page 23 © augustavop; page 24 © Csondy; page 25 © jarnogz; page 27 © Paul Tessier; page 28 © DonFink; page 29 © ericfoltz; page 30 © Liam Gumley/NASA; page 31 © FrankRamspott; page 32 © Constance Knox; page 33 © skynavin; page 35 © pancaketom; page 36 © unbancow; page 37 © Sandy Sandy; page 38 © Michael Luhrenberg; page 40 © MICHELANDELOBOY; page 41 © epicphotography; page 42 © photoquest7; page 43 © U.S. Army Corps of Engineers; page 44 © Naoki Uteda/AP Edited by: Jill Sherman Cover and Interior design by: Tara Raymo Library of Congress PCN Data Erosion / Shirley Duke (Let’s Explore Science) ISBN 978-1-62717-751-1 (hard cover) ISBN 978-1-62717-873-0 (soft cover) ISBN 978-1-62717-983-6 (e-Book) Library of Congress Control Number: 2014935676 48 Printed in the United States of America, North Mankato, Minnesota Also Available as: Expanding on our popular Let’s Explore Science series, this book focuses on erosion. How it’s caused, the effects it has on the current landscape, and the way it impacts our Earth are all explained. Great changes take place to form mountains and break apart the land. Erosion carries away broken rocks and soil through a process called weathering. Explore the tremendous ways our planet has changed in this fact-filled book on erosion. This book will allow students to use information from several sources to provide evidence that Earth events can occur quickly or slowly. TITLES IN THIS SERIES: Earth and Space Science Biofuels Climate and Weather Erosion Exploring the Solar System Geology Plate Tectonics and Disasters Rocks, Minerals, and Soil Rot and Decay: Decomposing and Recycling Sorting the Elements: The Periodic Table at Work Space The Earth and the Role of Water Understanding Biomes Weather History and Nature Of Science Physical Science Enjoy Your Meal: What Happens When You Eat? Environmental Disasters Going Green Infections, Infestations, and Diseases Our Footprint on Earth Restoring Wetlands Energy Floods, Dams, and Levees Forces and Motion at Work Ice to Steam: Changing States of Matter It’s Electric! Currents Microworlds Turn on the Light: How Electricity Works Waves of Light and Sound Life Science You Can’t Wear These Genes Science and Technology Science As Inquiry Animal Invaders Animal Science Biodiversity Cells Food Chains and Webs: The Struggle to Survive Food From the Sun: How Plants Live and Grow Fossils: Uncovering the Past Plants Out of Place The Nervous System Build it Green Built to Last Cell Phones Computers GPS Inventors and Discoveries Medical Technology and Engineering MP3 Players Solar Energy Thanks, NASA! The Internet and Email Video Games Wind Energy Enterprise STEM Hypothesis, Theory, Law Science Fair Success! Understanding Models Using Scientific Tools Using the Scientific Method rourkeeducationalmedia.com