Weathering and Soil Guide

Weathering and Soils Teacher’s Guide Middle School

Editors: Brian A. Jerome, Ph.D. Stephanie Zak Jerome

Assistant Editors: Sue Dier Louise Marrier

Graphics: Dean Ladago Fred Thodal

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National Standards Correlations 6

Student Learning Objectives 7

Assessment 8

Introducing the Video 9

Video Viewing Suggestions 9

Student Assessment and Activities 10

Video Script 11

Answers to Student Assessments 17

Answers to Student Activities 18

Assessment and Student Activity Masters 19

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Dear Educator:

Thank you for your interest in the educational videos produced by the Visual Learning company. We are a Vermont-based, family owned and operated business specializing in the production of quality educational science videos and materials.

We have a long family tradition of education. Our grandmothers graduated from normal school in the 1920’s to become teachers. Brian’s mother was an elementary teacher and guidance counselor, and his father was a high school teacher and superintendent. This family tradition inspired Brian to become a science teacher, and to earn a Ph.D. in education, and lead Stephanie to work on science educational programs at NASA.

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National Science Education Standards (Content standards: 5-8, National Academy of Sciences, c. 1996) Earth and Space Science – Content Standard D: As a result of their activities in grades 5-8, all students should develop an understanding that: • 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.

• 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.

Benchmarks for Science Literacy (Project 2061 – AAAS, c. 1993) The Physical Setting – Processes that Shape the Earth – (4C) By the end of 5th grade, students should know that: • Rock is composed of different combinations of minerals. Smaller rocks come from the breakage and weathering of bedrock and larger rocks. Soil is made partly from weathered rock, partly from plant remains, and also contains many living organisms.

By the end of 8th grade, students should know that:

• Although weathered rock is the basic component of soil, the composition and texture of soil and its fertility and resistance to erosion are greatly influenced by plant roots and debris, bacteria, fungi, worms, insects, rodents, and other organisms.

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Upon viewing the video and completing the enclosed student activities, students will be able to do the following:

• Describe the process of weathering.

• Differentiate between mechanical and chemical weathering.

• Describe some of the agents of mechanical weathering.

• Describe some of the agents of chemical weathering.

• Explain how acid rain causes weathering and damage to rocks.

• Identify the major components of soil.

• Describe the characteristics of humus and why it is important to plant growth.

• Explain why pore spaces are important to plants.

• Define the terms: texture, topsoil, horizons, and soil profiles.

• Identify the three layers of a mature soil profile.

• Differentiate between A, B, and C soil horizons, and describe the general characteristics of each horizon.

• Discuss how climate affects the soil characteristics of an area.

• Generally differentiate between the soil types in desert and grassland areas.

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Preliminary Test: The Preliminary Test, provided in the Student Masters section, is an assessment tool designed to gain an understanding of student preexisting knowledge. It can also be used as a benchmark upon which to assess student progress based on the objectives stated on the previous pages.

Video Review: The Video Review, provided in the Student Masters section, can be used as an assessment tool or as a student activity. There are two main parts. The first part contains questions titled “You Decide” that can be answered during the video. The second series of ten questions consists of a video quiz to be answered at the conclusion of the video.

Post-Test: The Post-Test, provided in the Student Masters section, can be utilized as an assessment tool following student completion of the video and student activities. The results of the Post-Test can be compared against the results of the Preliminary Test to assess student progress.

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Before showing the video, show the students a picture of a cracked sidewalk or a weathered tombstone. Ask students what forces do they think caused these changes. Write their ideas on the blackboard. Explain that the process of weathering breaks down rocks and other materials. Ask the students to list examples of weathering and write the examples on the board.

Next, bring in a soil sample for the students to examine. Ask the students what they think are the components of this soil. Have students take a close look at the soil sample with magnifying glasses. Try to identify some of the different soil components.

Tell students to pay close attention to the video to discover different types of weathering and the agents that cause weathering. Also listen carefully learn information about soil and soil profiles.

Video Viewing Suggestions

The student Master “Video Review” is provided for distribution to students. You may choose to have your students complete this Master while viewing the program or to do so upon its conclusion.

The program is approximately 20-minutes in length and includes a ten-question video quiz. Answers are not provided to the Video Quiz on the video, but are included in this teacher’s guide. You may choose to grade student quizzes as an assessment tool or to review the answers in class.

The video is content-rich with numerous vocabulary words. For this reason you may want to periodically stop the video to review and discuss new terminology and concepts.

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Assessment Masters:

• Preliminary Test

• Video Review

• Post-Test

Student Activity Masters:

• Dirt

• What is a Hoodoo?

• Vocabulary of Forces Weathering and Soil

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Video Script: Weathering and Soil

1. What forces caused the tombstones in this graveyard to become nearly illegible. 2. Why did this road become cracked, making for rough travel? 3. And what caused these once sharp bricks in this old building to become dull and bumpy? 4. What forces carved out these unusual pillars of rock? 5. And what gouged out the mile-deep Grand Canyon? 6. What is the fate of this rock that sits at the bottom of this cliff? 7. Where did the soil in this field come from? 8. And how is the soil in these beach dunes… 9. …different from that in this rose garden? 10. During the next few minutes we are going to answer many of these questions as we explore… 11. …the powerful forces of weathering. 12. …and look at some of the important characteristics of soil. 13. Graphic Transition – Weathering 14. Everyday we experience the weather when we walk outside. 15. Weather is the condition of the atmosphere. 16. But, the process of weathering is very different. 17. Weathering is the process that breaks down rocks and other objects into smaller and smaller pieces. 18. Weathering occurs all around us. 19. It is a very slow process that is not easy to observe in action, but its effects can be seen. 20. For example, a few years ago this building was freshly painted, but over time the paint peeled, chipped and fell off the wood as a result of weathering. 21. Thirty years ago this sidewalk was smooth and level. 22. But, over time the forces of weathering caused it to buckle and crack. 23. This iron grate used to be bright and shiny. 24. But, over time it became dull and rusty. 25. All objects on earthʼs surface, including rocks, are exposed to weathering. 26. There are two major types of weathering: mechanical weathering… 27. …and chemical weathering 28. Graphic Transition – Mechanical Weathering 29. You Decide! What would happen if you smashed this rock with a hammer? 30. The rock breaks into smaller pieces. 31. A similar process occurs in mechanical weathering.

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32. Mechanical weathering involves the breaking down of rocks into smaller and smaller pieces, but the rocks are not chemically changed. 33. For example, hundreds of these smaller rock fragments were once part of the massive rock above. 34. But, over time gravity pulled them down, they broke apart, and were further chipped away via the process of mechanical weathering. 35. The downward pull of gravity is one important agent of mechanical weathering. 36. One of the most amazing agents of mechanical weathering involves plants. 37. Surprisingly, plants have the ability to use their roots to wedge apart rocks, breaking them into smaller pieces. 38. Fluctuations in temperature can also play a big role in mechanically weathering rocks. 39. During daylight hours the sun heats rocks causing them to expand. 40. …while cooler nighttime temperatures cause them to contract. 41. This repetitive process of expansion and contraction can cause rocks to break apart. 42. You Decide! What do you think will happen to this water filled glass container if we place it in the freezer overnight? 43. The bottle broke. Why? 44. When water freezes, it expands, sometimes with great force. 45. When wedged between cracks in these rocks, water can freeze, expand, and over time force rocks apart in a process referred to as frost action 46. Freezing and thawing played a vital role in weathering these rocks in Utah. 47. These are just a few of the ways rocks are worn down by mechanical weathering. 48. Letʼs now look at the process of chemical weathering. 49. Graphic Transition – Chemical Weathering 50. The rocks surrounding these geothermal hot springs are being changed before our eyes. 51. Even though you canʼt see it, chemical compounds in the steam and water are altering the rocks in a process called chemical weathering. 52. Chemical weathering is quite different from mechanical weathering. 53. In chemical weathering, rocks are broken down in a process that actually changes a rockʼs chemical makeup. 54. It is a common occurrence and water is the agent most responsible for chemical weathering. 55. For example, when rainwater mixes with carbon dioxide in the air, an acid called carbonic acid is formed.

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56. Carbonic acid has the ability to alter many rocks, such as calcilite, marble, and limestone, breaking them down chemically. This process played a major role in weathering this marble tombstone. 57. Rocks and metals containing iron rust via a type of chemical weathering called oxidation. 58. In the process of oxidation, oxygen in the air combines with iron in a rock or a piece of metal containing iron … 59. …to form iron oxide, also known as rust. 60. You Decide! What is acid rain? 61. Acid rain is snow or rain which is more acidic than normal. 62. It is formed when certain pollutants such as sulfur dioxide are released into the air from burning coal and oil. 63. In the atmosphere, sulfur dioxide combines with water vapor to form dangerous substances such as sulfuric acid. 64. These substances fall to earth as acid rain. 65. Acid rain is not only harmful to our forests and wildlife… 66. …it can also cause chemical weathering of rocks like this limestone… 67. …or even damage buildings and statues. 68. Graphic Transition - Soil 69. Have you ever thought about how important soil is to us? 70. All living things on land depend on soil in one way or another. 71. Most plants grow in soil. 72. And many animals and humans eat fruits and vegetables that grow in the soil. 73. You Decide! What exactly is soil? 74. Soil is a mixture of pieces of rock, air, water, and once living things. 75. There are many different things and processes that go into the formation of soil. 76. And there are many different kinds of soil. 77. One of the most important ingredients found in soil is rock fragments. 78. Through the process of weathering, rock is broken down into smaller and smaller pieces. 79. You Decide! Could plants easily grow in this gravel? 80. No, plants cannot easily take root, grow, and reproduce in just rock fragments. 81. Plants and other things that live in soil need decomposed material to live on. 82. Humus is made up of once living, decomposed material. 83. Dead plants, animals, and leaves contribute to the formation of humus. 84. Humus tends to be dark colored,… 85. …and it provides valuable nutrients for plants; and helps retain water.

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86. Good, rich soil contains a lot of humus. 87. Soil is continuously forming as particles of rock and humus are added… 88. Soil also contains a great deal of air which occupies spaces between particles called pore spaces. 89. Water may also occupy pore spaces. 90. Pore spaces are very important to plants because they hold water and gases that plants need. 91. Living things such as bacteria, insects, worms,… 92. …and even prairie dogs may also live in the soil. 93. Different soils have different texture. Texture is the size of soil particles. 94. For example, this soil in beach dunes has a sandy texture, made mostly of sand. 95. And this soil has a clay-like texture. 96. Graphic Transition – Soil Profile 97. Have you ever been to a construction site where heavy equipment was digging through the soil… 98. …and you noticed different soil layers. 99. When soil forms, it develops layers called horizons. 100. A side view or cross-sectional view like this one is called a soil profile. 101. Different horizons have different characteristics. 102. Generally speaking, mature soil contains three horizons. 103. The uppermost horizon called the A horizon is the youngest layer. 104. The A horizon is often dark colored, and contains large amounts of humus. 105. When you work in the soil such as planting a garden, you are in the A horizon. 106. It is often called topsoil. Topsoil is nutrient rich, and provides needed water and nutrients for plants that absorb them through their roots. 107. Beneath the A horizon is the next soil layer called the B horizon. 108. The B horizon tends to be a lighter color than the A horizon and contains less humus than the A horizon. 109. Some minerals may wash into the B horizon via a process called leaching. 110. The roots of plants and trees may extend into the B horizon, which is sometimes called subsoil. 111. Lying under the B horizon is the C horizon, the bottom layer in the soil profile. 112. The C layer consists of partially weathered rock… 113. …and its composition is similar to that of the bedrock which underlies it. 114. This is a much-simplified look at the soil profile. 115. The specific make-up and thickness of soil horizons varies greatly from place to place.

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116. Graphic Transition – Soil Types 117. The soil in this dry desert is very different… 118. …from the soil in this prairie grassland. 119. Desert soils tend to be quite dry, with limited amounts of humus. 120. Whereas the soil here in this grassland is well developed with a thick layer of topsoil. 121. And the soil here in New England is relatively thin and rocky. 122. One of the biggest factors which affects the thickness and characteristics of soil in a region is climate. 123. Drier areas such as deserts tend to have thinner soil… 124. …than moister climates. 125. Slope also affects soil type. 126. For example, in this region mountaintops and slopes tend to have very thin soils. 127. But bottomlands in river valleys tend to have much deeper soil profiles. 128. There are hundreds of different soil characteristics and soil types. 129. Graphic Transition _ Summing Up 130. During the past few minutes we have taken a look at some of the characteristics and processes of weathering. 131. We explored some of the ways mechanical weathering acts on rocks. 132. As well as some of the characteristics of chemical weathering. 133. And we have looked at the vital role these processes play in breaking down rocks. 134. We also discussed some of the components of soil including humus, rocks, air, and water. 135. And we briefly explored how soil is formed. 136. We took a look at soil profiles and saw how soil forms layers called horizons. 137. Finally, we took a quick look at how soils differ from each other from place to place. 138. So, the next time you see weathered rocks… 139. …dig in the soil around your house… 140. …or admire flowers growing in a garden, think about some of the things we have discussed during the past few minutes… 141. You just might look at the world a little differently. Fill in the correct word to complete the sentence. Good luck and letʼs get started. 1. ______involves the breaking down of rocks 2. Gravity is a major agent of ______weathering. 3. Rocks surrounding these geothermal springs are being changed ______.

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4. Rusting involves the process of ______. 5. ______rain can weather rocks. 6. ______is a mixture of rock, air, water and once living things. 7. ______consists of once living decomposed material. 8. ______spaces contain water and gases. 9. Soil layers are called ______. 10. Mature Soil tends to have ______distinct layers.

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Preliminary Test (pgs. 20-21) Video Quiz: (pg. 22 1. chemical weathering 1. weathering 2. texture 2. mechanical 3. A horizon 3. chemically 4. acid rain 4. oxidation 5. climate 5. acid 6. frost action 6. soil 7. C horizon 7. humus 8. grassland 8. pore 9. temperature 9. horizons 10. topsoil 10. three 11. true 12. false Post Test (pgs. 23-24) 13. true 1. true 14. true 2. false 15. true 3. true 16. false 4. false 17. false 5. true 18. true 6. false 19. false 7. true 20. false 8. false Video Review (pg. 22) 9. true 10. false 1. The rock will break into smaller pieces. 11. climate 2. The bottle breaks because when water 12. C horizon freezes, it expands. 13. chemical weathering 3. Acid rain is snow or rain which is more 14. texture acidic than normal. 15. acid rain 4. Soil is a mizture of pieces of rock, air, 16. topsoil water, and once living things. 17. A hoizon 5. No, plants cannot easily take root, grow, 18. frost action and reproduce in just rock fragments. 19. temperature 20. grassland

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Answers to Student Activities

Dirt (pg. 25) 1, 2, 3, 4. You should select sites for the soil test pits before going outside with your students. Try to select sites that may produce some variation. Answers to the questions will vary depending on the characteristics of individual soil test pits.

What is a Hoodoo? (pg. 28)

1. Hoodoo is an African word meaning “to cast a spell”. 2. A hoodoo is a pillar of rock created by the forces of weathering and erosion. 3. Chemical weathering continually eats at susceptible rocks containing calcium carbonate. 4. Mechanical weathering in the form of frost and moving water gradually play a role in carving out the vertical columns. 5. Acid rain, as in chemical weathering, can increase the rate of which hoodoos are weathered.

Vocabulary (pg. 30) 1. soil profile, e 2. weathering, j 3. mechanical weathering, d 4. oxidation, f 5. topsoil, h 6. texture, a 7. horizon, i 8. soil, c 9. chemical weathering, g 10. humus, b

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Activity Masters

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Directions: Fill in the blank with the correct word. A list of possible answers is provided at the bottom of the page.

1. ______is the process of breaking down rocks during which their chemical composition is changed.

2. ______refers to the size of soil particles.

3. The ______is the uppermost soil level and contains large amounts of humus.

4. ______can cause the chemical weathering of some rocks.

5. ______has a large influence on the soil characteristics of an area.

6. ______refers to mechanical weathering caused by the freezing and thawing of water.

7. The ______is the bottom layer of a soil profile and consists of partially weathered rocks.

8. Soil that is well developed with a thick layer of topsoil is often found in ______areas.

9. ______fluctuations can cause the mechanical weathering of rocks.

10. ______is nutrient rich soil and provides needed water and nutrients for plants.

horizon C climate acid rain texture mechanical weathering frost action chemical weathering horizon B desert temperature horizon A grassland topsoil

®2003 ®2003 20 21 Weathering and Soils Name Weathering and Soils Name Preliminary Test

Directions: Decide whether the answer is True (T) or False (F).

11. Rock fragments are an important component of T F soil.

12. Humus consists mostly of rocks and clay particles. T F

13. Plants have the potential to cause mechanical T F weathering.

14. Desert soils tend to be dry with a limited amount of T F humus.

15. Water is the agent mostly responsible for chemical T F weathering.

16. Acid rain is a cause of mechanical weathering. T F

17. The C horizon consists of primarily humus. T F

18. Gravity is one important agent of mechanical T F weathering.

19. Mountaintops tend to have a thick layer of topsoil. T F

20. Chemical weathering is an uncommon occurrence. T F

®2003 ®2003 20 21 Weathering and Soils Name Weathering and Soils Name Video Review

Directions: During the course of the program, answer the “You Decide” questions as they are presented in the video. Answer the Video Quiz questions at the end of the video. You Decide: 1. What will happen to this rock? Answer ______

2. What will happen to this water filled glass Answer ______container if we place it in the freezer overnight?

3. What is acid rain? Answer ______

4. What is soil? Answer ______

5. Could plants easily grow in this gravel? Answer ______

Video Quiz: 1. ______involves the breaking down of rocks.

2. Gravity is a major agent of ______weathering.

3. Rocks surrounding these geothermal springs are being changed ______.

4. Rusting involves the process of ______.

5. ______rain can weather rocks.

6. ______is a mixture of rock, water and once living things.

7. ______consists of once living decomposed material.

8. ______spaces contain water and gases.

9. Soil layers are called ______.

10. Mature soil tends to have ______distinct layers.

®2003 ®2003 22 23 Weathering and Soils Name Weathering and Soils Name Post Test

Directions: Decide whether the answer is True (T) or False (F).

1. Gravity is one important agent of mechanical T F weathering.

2. Acid rain is a cause of mechanical weathering. T F

3. Plants have the potential to cause mechanical T F weathering.

4. Chemical weathering is an uncommon occurrence. T F

5. Rock fragments are an important component of T F soil.

6. Mountaintops tend to have a thick layer of T F topsoil.

7. Desert soils tend to be dry with a limited amount of T F humus.

8. The C horizon consists of primarily humus. T F

9. Water is the agent mostly responsible for chemical T F weathering.

10. Humus consists mostly of rocks and clay particles. T F

®2003 ®2003 22 23 Weathering and Soils Name Weathering and Soils Name Post Test

Directions: Fill in the blank with the correct word. Choose from the list of possible answers at the bottom of the page.

11. ______has a large influence on the soil characteristics of an area.

12. The ______is the bottom layer of a soil profile and consists of partially weathered rocks.

13. ______is the process of breaking down rocks during which causes their chemical composition to change.

14. ______refers to the size of soil particles.

15. ______can cause the chemical weathering of some rocks.

16. ______is nutrient rich soil and provides needed water and nutrients for plants.

17. The ______is the uppermost soil level and contains large amounts of humus.

18. ______refers to mechanical weathering caused by the freezing and thawing of water.

19. ______fluctuations can cause the mechanical weathering of rocks.

20. Soil that is well developed with a thick layer of topsoil is often found in ______areas.

grassland chemical weathering horizon C texture temperature desert acid rain climate horizon B horizon A mechanical weathering topsoil frost action

®2003 ®2003 24 25 Weathering and Soils Name Weathering and Soils Name

Dirt

Objective: Students will study an actual soil profile, and analyze the soil horizons within the profile.

Background: All living things either directly or indirectly depend on the soil. Most plants are anchored in the soil, draw water from the soil, and extract valuable nutrients from the soil. In turn, most animals that live on land eat plants that grow in the soil, or eat other animals that eat plants. Just think of all the fruits and vegetables you eat every day that grow in soil.

What exactly is soil? Rocks, water, air, living things, and even bacteria make up soil. The two main ingredients – weathered rock and organic material vary greatly from place to place. In turn, the amount of water found in the soil varies greatly depending on the time of year. The texture or size of soil particles also varies greatly from place to place. For example, gravel ranges in size from 2 to 64 millimeters. Particles of sand are about 2 millimeters in diameter and clay particles are even smaller.

Over many, many years soil develops layers referred to as horizons. The type of material and depth of each horizon varies from location to location. A cross-section view of soil is referred to as a soil profile. Mature soil tends to have three distinct layers. The top layer, also called the A horizon, contains a great deal of once living material called topsoil. Topsoil tends to be dark colored and is home to bacteria, earthworms, and is the place where plants obtain nutrients and most of their water. Just below the A horizon is the B horizon, also called subsoil. This soil contains some minerals washed down from the A horizon via the process of leaching process, and some small amounts of humus. Underlying the B horizon is the C horizon. This layer consists of partially weathered rock coming from bedrock beneath it.

Keep in mind that soil textures and soil profiles vary greatly from place to place. While mature soil tends to have three relatively well defined layers, immature soil usually does not. Many factors affect soil formation including climate, slope, parent rock and living things.

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Dirt Material: Shovel, measure tape, copy of the data table, and paper. Directions: 1. Select an area outside where you have permission to dig a soil profile hole. 2. With a shovel dig a hole approximately two feet by two feet and two feet deep. 3. Once you have finished digging, take a close look at the soil profile. Measure the thickness and depth of each soil horizon. Also, describe the color of the horizon and record it in the data table. 4. Make a sketch of the soil profile. 5. Next, take a soil sample of the bottom horizon. Place the sample on a piece of paper for closer examination and describe the color and texture. Is the soil made of particles of clay or sand, or is it made of pebbles? 6. Analyze the soil in the other horizons as well, and record your answers in the data table. 7. If time permits, dig a second soil test pit and compare the soil profile to your first one. 8. When you are finished, fill in your soil test pits!

Soil Data Table

Depth Thickness Color Soil Texture Horizon A

Horizon B

Horizon C

®2003 ®2003 26 27 Weathering and Soils Name Weathering and Soils Name

Dirt

Questions: 1. How many horizons were easily distinguishable in your soil test pit?

2. Describe the natural vegetation near your soil test pit?

3. Do you think the soil is mature or immature? How would it be for growing crops?

4. Describe some other factors which you think might affect the nature of the soil you studied.

®2003 ®2003 26 27 Weathering and Soils Name Weathering and Soils Name

What is a Hoodoo? Objective: Students will learn how the forces of weathering affect the formation of hoodoos in Utah. Background: If you were to visit Bryce Canyon National Park you would see some of the most unusually shaped geologic features on the planet. In one canyon, hundreds of pillars called hoodoos point skyward in a sea of red and orange colored rock. Hoodoo is an African word meaning “to cast a spell.” There is no doubt that these enchanting formations are not only breathtakingly beautiful, but also mesmerizing.

What exactly is a hoodoo? A hoodoo is a pillar of rock, usually of remarkable shape, created by the forces of weathering and erosion. Between 63 and 40 million years ago, rivers and streams carried limestone (containing calcium carbonate) and iron-rich sediments into a large freshwater lake. These sediments were deposited to form the reddish pink rocks from which hoodoos are formed. Over millions of years these rocks were uplifted, covered by volcanic materials, and tilted. The forces of weathering and erosion eventually exposed the red, pink and orange rocks we now see today.

Different types of weathering play a key role in forming hoodoos. Chemical weathering, primarily the action of carbonic acid found in rainwater, continually eats at susceptible rocks containing calcium carbonate such as limestone. Water enters small holes in rocks and dissolves cement which hold rocks together.

Moving water mechanically scours and abrades rocks. Along the rim of the steep walled canyon fast moving water generally forms gullies. Repetitive cycles of freezing and thawing also loosen slope surfaces. Between gullies lie piers of rock which jut out into the canyon.

Mechanical weathering in the form of frost action and moving water gradually play a role in carving out vertical columns, which we know as hoodoos. These are just a few examples of some of the agents of weathering involved in the creation of the rock columns that “cast a spell.”

®2003 ®2003 28 29 Weathering and Soils Name Weathering and Soils Name

What is a Hoodoo?

Questions: 1. What does the word hoodoo mean?

2. What are hoodoos?

3. What role does chemical weathering play in hoodoo formation?

4. What role does mechanical weathering play in hoodoo formation?

5. What factors do you think would decrease or increase the rate of which hoodoos are weathered?

®2003 ®2003 28 29 Weathering and Soils Name Vocabulary of Weathering and Soil

Directions: Unscramble the vocabulary words in the first column. Match the words to the definitions in the second column.

____1) ilso foleirp ______a. refers to the size of the soil particles. ____2) ingeeawthr ______b. part of the soil consisting of once living ____3) aaniclchem ______c. a mixture of pieces of rock, air, water, thingereaw and once living things. ____4) aoodiixnt ______d. the weathering of rocks that does not involve changing the chemical ____5) oospilt______composition of the rocks.

____6) eetturx ______e. a side or cross-sectional view of soil.

____7) oorizhn ______f. the process by which oxygen in the air

combines with iron in a rock or piece ____8) ilos ______of metal containing iron to form iron oxide, also known as rust. ____9) emcailhc ______

eeargnithu g. the breaking down of rocks which causes their chemical makeup to ____10) uumsh______change.

h. upper portion of soil profile which is nutrient rich, and provides needed water and nutrients for plants.

i. a layer of soil.

j. the process by which rocks and other materials are broken down into smaller and smaller pieces.

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