Science indicator following this activity: 4.3.5---- Describe how waves, wind, water, and glacial ice shape and reshape the Earth’s land surface by erosion of rock and soil in some areas and depositing them in other areas. Activity taken from: http://www.indianastandardsresources.org/files/sci/sci_4_3_5.pdf
Purpose Students will investigate and describe how wind and water reshape Earth’s surface of rock and soil. View slide
Vocabulary Erosion--- the gradual (slow) wearing away of land surface materials, especially rocks, sediments, and soils, by the action of water, wind, or a glacier. View slide
Background Information Are you ever curious when you see two large formations separated by water? If you see a rock, pull it out of a mountain. Then throw it down on the ground. You are now part of the erosion of that mountain. You have taken a big object (a mountain) and started to make little objects out of it (a rock). When that rock hit the ground, it could have cracked and made some tiny pieces of rock (sand). When it rains, the same process happens. Rocks are washed down a mountain or down a stream. Soils are washed away. The ocean beats against a cliff and breaks it apart.
Pre-Activity What are some things that change the surface of the Earth? Looking at the photographs- 1. What is the picture showing? 2. Where do you think the pictures were taken? 3. Do you think the formations have always looked like that? You do not have to write anything down, just think to yourself.
Lets begin the activity! Pull out the worksheet that says “Nature’s Bulldozer.” Make sure you have a pencil as well. Place a thin layer of gravel along the slope of each paint tray. Add a thin layer of sand to each tray as well. Be sure to leave the base of each tray empty. Draw the experiment set-up on the worksheet in the provided box. “If I were to blow (like the wind) on one of these models, what do you think might happen to the sand? What might happen to the gravel? Would the model stay the same or change?” Draw what you predict the model will look like after blowing. (Answer the questions on the next slide) After you complete your drawing from the prediction, blow on one of the models for ten seconds. Record what happened to the model in the provided space on the worksheet.
Questions: What did the air do to the sand? What did the air do to the gravel?
Was your prediction correct? What effects of air have you seen in real life that helped you make your predictions?
Activity Continued…. With the second model, draw in the provided space what you think the model will look like after the water is poured over the gravel and sand. Pour the water over the gravel and sand. Record what happened in the space provided on the worksheet.
Questions: What did the water do to the sand? What did the water do to the gravel?
Was your predictions correct? What effects of water have you seen in real life that helped make your prediction?
Summary By using wind and water, the models showed erosion of soil. Erosion is the process by which wind and moving water carry away bits of rock and soil. Inform students that you used a bottom layer of gravel and a top layer of sand to show how different types of earth are placed naturally. Discuss with students how gravel is heavier than sand, so it would naturally sit on the bottom. Ask students, “Do you think that gravel and sand can always be moved by the same wind and water forces?”
References: http://www2.scholastic.com/browse/article.jsp?id=2849 This website is great for students to visit to learn more about erosion. http://www.youtube.com/watch?v=lyysL02ZvQ8 This video gives basic information about erosion and weathering. http://www.youtube.com/watch?v=F0Xq4Zkb6BE Here is a video like the activity I have students doing to show how erosion works. http://www.indianastandardsresources.org/files/sci/sci_4_3_5.pdf This is the website which I received the activity off of.