Science SCI.V.I.3 Grade: 7 Strand V: Using Scientific Knowledge in Earth Science Standard 1: Geosphere ­ All students will describe and explain how the earth’s features change over time. Benchmark 3: Explain how rocks are broken down, how soil is formed and how surface features change. Constructing and Reflecting: SCI.I.1.1 ­ Generate scientific questions about the world based on observation.
· Construct questions for each of the investigations suggested below to guide the design of the investigation. SCI.I.1.2 ­ Design and conduct scientific investigations. SCI.I.1.3 ­ Use tools and equipment appropriate to scientific investigations. SCI.I.1.4 ­ Use metric measurement devices to provide consistency in an investigation. SCI.I.1.6 ­ Write and follow procedures in the form of step­by­step instructions, formulas, flow diagrams, and sketches. SCI.II.1.1 ­ Evaluate the strengths and weaknesses of claims, arguments, or data. SCI.II.1.3 ­ Show how common themes of science, mathematics, and technology apply in real­world contexts. SCI.II.1/2 ­ Describe limitations in personal knowledge. SCI.II.1.4 ­ Describe the advantages and risks of new technologies. SCI.II.1.5 ­ Develop an awareness of and sensitivity to the natural world. Vocabulary / Key Concepts Context Chemical and mechanical weathering Regions in Michigan where erosion by wind, water, or glaciers may have occurred:
· river valleys
· gullies
· shoreline of Great Lakes
· along the shoulder of roads
· under downspouts
· chemical weathering from acid rain
· formation of caves
· caverns and sinkholes Erosion by:
· glaciers
· water
· wind
· down ­slope movement Decomposition (Chemical Weathering) by:
fungi
lichens ·
·
Physical weathering from frost action:
· potholes
· cracks in sidewalks Plant roots by:
· Bacteria
· Fungi
· worms
· rodents
· other animals
Knowledge and Skills Resources Soil formation is related to physical and chemical Coloma Resources weathering that breaks down rocks and changes Rock & Roll lab: the surface of the earth. Students will explain how Marble chips are measured and then shaken in weathering, erosion and decomposition contribute jars of water and then remeasured. This shows to soil formation. Students will explain how erosion, and weathering. physical weathering ( i.e. frost action, water and wind ) and chemical weathering ( i.e. acid rain and Soil Testing lab: pages 70­71 (Prentice Hall’s by­products of decomposers) change surface Earth’s Waters.) – Lab in book features. Shows permeability of soils and how they affect the aquifer – extension – how well drillers, gardeners, farmers use this information. Other Resources:
· Globe Soil Science Education Home Page – Awesome, enormous site with TONS of info on soil from your friends at NASA.
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Soil Formation Links – Soil Science Education
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ThinkQuest – Get Ready to Rock – Rock info, activities, games and more.
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Franklin Institute – Rocks and Minerals – links to many web sites with LOTS of info!
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UCMP Berkeley – Geology Wing – History of the Earth timeline in geologic timescale including fossils.
Other Resources (Continued from column at right)
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·
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USDA – National Resources Conservation Service ·
– Soils Web Site – Huge resource with LOTS of soil ·
information. AWESOME.
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Bill Nye: Atmosphere, Earth Quakes, Earth Crust, Rocks & Soil, Volcanoes
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Plate Tectonics – USGS – This Dynamic Earth
UND – Volcano World – premier web site of volcano info.
Michigan Teacher Network Resources
MEADE Video – Strip Mining vs. Open Pit Mining ·
Videoconferences Available For more information, see www.remc11.k12.mi.us/dl or call Janine Lim 471­7725x101 or email ·
jlim@remc11.k12.mi.us V.1.MS.3 Explain how rocks are broken down, how soil is formed and how surface features change Ice Age from Cranbrook Institute of Science Iowa State Univ. Earth Science Weblinks – extensive and awesome!!
DETERMINATION OF SOIL TEXTURE IN THE FIELD: ­ soil texture decision chart and soil triangle – reproducible with lots of soil info! NICE! 28 page text on soils by UC Santa Cruz.
Instruction Focus Question: How does a glacier move and shape the earth? Day 1 (Preparation)
· Fill ¼ of small container with sand and rocks.
· Fill the rest of the container with water.
· Close the container, tape it, shake it, label it, and freeze it! Day 2
· Remove the ice from the small container and place your “glacier” on the soil mound, debris side down.
· Once ice has melted observe the results. (Depending on the size of the “glacier”, you may need to observe the next day.) Assessment Optional Assessment Assessment I Students will draw a picture of an outdoor scene labeling several types of erosion. Assessment II Each student will write an essay that answers the following questions:
· How does the soil type affect the amount of water that is filtered or remains on the surface?
· How does that water contribute to surface erosion?
· How does that water contribute to the creation of landforms such as caves, gullies, etc.? Each student will create a visual aid (i.e., a picture, map, 3D model) that lists the three basic soil types and describes their characteristics. Each student will orally present his or her essay and visual aid to the class. (Give students rubric before activity.) Scoring Rubric Criteria: Accuracy of essay Apprentice ­ Writes an essay that is irrelevant to topic. Basic ­ Writes an essay that states basic terms. Meets ­ Writes an essay that is accurate and elaborates on relevant concepts. Exceeds ­Writes an essay that contains no contradictions and elaborates on all relevant concepts and terms in detail. Criteria: Correctness of visual aid Apprentice ­ Identifies three soil types. Basic ­ Identifies three soil types and shows the relationship between soil and one factor. Meets ­ Identifies three soil types and shows the relationship between two soil types and studied factors. Exceeds ­ Identifies three soil types and shows the accurate relationship between all soil types and studied factors. Criteria: Effectiveness of presentation Apprentice ­ Presents limited information relevant to the topic. Basic ­ Presents information that is relevant to the topic and demonstrates an effort to organize that information. Meets ­ Presents an accurate, interesting, and organized report. Exceeds ­ Presents an interesting and accurate program that is clearly focused.
Teacher Notes: “Land forms are the result of a combination of constructive and destructive forces. Constructive forces include crustal deformation, volcanic eruption, and deposition of sediment, while destructive forces include weathering and erosion.
· Soil consists of weathered rocks and decomposed organic material from dead plants, animals, and bacteria. Soils are often found in layers, with each having a different chemical composition and texture. Focus Question
·
How does weathering and erosion change the Earth’s surface and how does soil form?
PROBLEM What effect does the length of time of abrasion have on the way rock particles weather (change)? MATERIALS Can with lid Presoaked rock chips Triple beam balance Screen Clock PROCEDURE 1. Obtain a sample of presoaked rock chips and remove the excess water. Use the screen to do this. 2. Use the balance to measure out 100 g. 3. Add water to the can until it is about half full. Close the can and shake it continually, for 3 minutes. 4. Carefully pour the water from the can into a sink. Use the screen so that none of the rocks are lost. 5. Measure the mass of the chips again and record your results in a data table. 6. Return the rock chips to the can, close it, and repeat the procedure. Do this 4 more times. Enter your results each time in your data table. 7. Graph the results, comparing mass remaining with the time of shaking. CONCLUSION 1. Why were the rock chips presoaked before you used them? 2. From your data table, describe how the mass changed through time. 3. What did you learn from this lab about the world around you?
33 PRENTICE HALL EARTH SCIENCE Chapter 15 Weathering and Soil You may want to refer students to pages 386­392 in their text for a general discussion of weathering. Time required: 40 minutes Background Information Substances on the earth are constantly undergoing change. One type of change occurs when rocks are broken into smaller pieces and then rounded as they are moved about in rivers and streams. This kind of change is known as a physical change. The process of rubbing and bumping together that causes this kind of physical change is called abrasion. In this investigation, you will observe the physical changes that rocks undergo through the process of abrasion in a model situation. Problem What effect does length of time of abrasion have on the way rock particles weather? Materials (Per group) Bottle, jar, or can with lid Plastic refrigerator jars with wide mouths work well. Presoaked rock chips Rocks should be shale, marble, or gypsum. Marble chips from a local gardening store would work well. Triple­beam balance Screen Clock or timer Use pieces of window screen cut to size. Procedure 1. Obtain a sample of presoaked rock chips and drain them to remove excess water. Note: Place the rocks on the screen so that they do not get lost. The sample student select could be a couple of handfuls in a paper towel. Soak the chips overnight. Have students pat off excess water with paper towels. 2. Use the balance to measure out 100 g of rock from your sample. Return the extra pieces to the supply container. 3. Place the 100 g of chips in the container provided. 4. Add water to the container until it is about half full. Close the lid tightly over the container. Shake the container at a constant rate for 3 minutes. You can use taped music to provide a regular beat.
5. Carefully pour the water from the container into a sink. Use the screen to make sure not even the smallest rock piece is lost. 6. Measure the mass of the chips again and record your result in the Data Table. 7. Return the rock chips to the container, close the container, and repeat steps 4 through 6 four more times. Record the results after each 3 minutes of shaking, for a total of 15 minutes. 8. Graph the results, comparing mass remaining with time of shaking. Weathering time (min) Mass of rock remaining (g) 0 100 3 6 Answers will vary 9 12 15 Actual results will vary, but the general trend will show more rapid loss in the first few seconds.
Name Class Date Conclusions 1. Why were the rock chips presoaked before you used them? To account for the mass of water that would be picked up during the first shaking period. 2. As you examined the rock pieces after each shaking period, how did the amount of rounding change as the abrasion time increased? Chips lost roughest edges first, then other less rough edges next, becoming more round through time. 3. From your data table, describe how the mass remaining changed through time. It decreased, at first rapidly, then slowly. 4. Did the difference in mass remaining at the end of each shaking period change in a regular manner. No. Explain why you think the mass remaining changed in the way that it did. The most mass was lost during the first and second period because that was when the rough edges were worn off. 5. What do you think might happen to the rate (speed) at which the rock chips were being worn away if you continued to shake them for an hour? It would decrease, even though the chips would continue to abrade. 6. What effect do you think the shape of the rock chips had on the rate of abrasion? The rougher the rock the faster the rate. The smoother and rounder the rock the slower the rate. Critical Thinking and Application 1. How do you think the hardness of a rock would affect the rate at which it would weather? Soft rocks will weather more rapidly than hard rocks. 2. Do you think the rate at which water moves over a rock affects how rapidly the rock weathers? Explain your answer. Yes. A rock weathers more rapidly by fast­moving water than by slow­moving water. 3. The pyramids that were built thousands of years ago in the deserts of Egypt have experienced some weathering due to abrasion. What do you think is responsible for this abrasion? Sand found in the deserts of Egypt causes weathering as it blows past the pyramids. The abrasive texture of the sand slowly wears down the surfaces of the rocks.
Going Further Repeat the procedure with rock salt (halite) chips of the same size. Describe any differences in the rate of abrasion that you observed between the halite and the rock chips that you used the first time. Explain why you think the rock salt weathered in the way that it did.