ROCKS OF THE GRAND CANYON BACKGROUND INFORMATION FOR DOCENTS

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1 ROCKS OF THE GRAND CANYON BACKGROUND INFORMATION FOR DOCENTS There are three distinct types of rock. Igneous rocks. Igneous comes from the Greek word for fire. It is so hot deep in the Earth that rocks have melted. The pressure is so tremendous that melted rock (magma) will push up through the Earth s crust, like in a tube of toothpaste. Sometimes a volcano is created. As lava (magma which has reached the Earth s surface) cools, igneous rock is formed. Basalt is an example of a quick cooling rock. All igneous rocks do not cool the same way, which is why they don t look alike. Ex: basalt, rhyolite, obsidian, granite Sedimentary rocks. Rocks on the Earth s surface are constantly being broken (eroded) up by wind, water, and ice. Small pieces tumble down rivers and over time are pressed together into solid sedimentary rock. Some sedimentary rocks are cemented together by minerals dissolved in water. Most sedimentary rocks form under water and are often rich with fossils. Ex: sandstone, limestone, conglomerate Metamorphic rocks. Metamorphic comes from the Greek word meaning change. Metamorphic rocks form deep in the Earth where high temperatures, great pressure and chemical reactions cause one type of rock to become another type. If you squeeze and heat a rock for a few million years, it can turn into a new kind of rock. Ex: limestone becomes the metamorphic rock marble, sandstone becomes quartzite, shale becomes slate. The metamorphic rock schist can form from shale, granite or volcanic rocks. Rock cycle (grade 7). The rock cycle is an ongoing recycling process that has shaped the earth in the past and continues to shape it today. Igneous rocks might roll down a mountain formed by a volcano. As they roll, pieces of igneous rocks are broken and form sediments, which then are pressed and cemented together forming sedimentary rocks. Some of the sedimentary rocks on the very bottom get hot because of the extreme pressure form rocks above and they might change into metamorphic rock. When metamorphic rock is buried deeper, it gets hotter and melts and once again may eventually be pushed up and out of a volcano. These changes are part of the rock cycle, which moves in such slow motion that geologists measure these movements in geologic time. To a geologist, a million years is just a blink of an eye.

2 ROCKS OF THE GRAND CANYON PROGRAM PLAN FOR DOCENTS The following is a suggested format for this program. Please feel free to incorporate your own experiences and creativity; however, try to maintain the Arizona State Academic Standards when you do this program. AGE/GRADE LEVEL This program is appropriate for grades 3 7. Rock types are introduced in grade 3. Classification of rocks and minerals and the rock cycle are introduced in grade 7. DURATION Approximately 1.5 hours (grade 3 4) 2 hours (grade 5 7) GROUP SIZE DOCENTS LOCATION BACKGROUND ESSENTIAL QUESTIONS 30 students plus one educator/chaperone for each six students 2 docents Begin tour in Branigar, continue tour with half group at a time in Geology Gallery for Activity 2 or Activity 4, other half remains in Branigar for Activity 1, 3 or 5 This program should help students identify the three rock types the Earth is made of and to begin to understand that rocks are fascinating ways to discover information about their origin and that of the history of the Earth, as well. Most of the rock layers found at Grand Canyon are sedimentary, laid down over long periods of time by rivers and seas. A small amount of the sedimentary rock was deposited by desert winds. The oldest rock found at the bottom of the Canyon is metamorphic (rock formed by heat and pressure). Igneous rock, seen in the inner gorge and in the Western part of Grand Canyon, was formed by hot, molten rock called magma that cooled either below or on the Earth s surface (then called lava). The marvel of Grand Canyon is that its rock layers are so beautifully exposed. By the end of the end of the program, students should be able to answer the following question: 1. Where do rocks come from? How do rocks differ from each other? Are all rocks formed the same way? What are the three types of rock? 2. Which of the rock types would you expect to be most prevalent in the Grand Canyon? Why? 3. Why do you think geologists learn by studying rocks? (grades 3 5) Why is determining the age of rocks important to understanding the history of the earth? (grades 6 7) KEY WORDS Crust Sedimentary Rock cycle (grade 7) Mantle Metamorphic Core Texture Igneous Fossil

3 MATERIALS NEEDED INTRODUCTION Picture of Grand Canyon, apple and a knife to slice it (or Earth Balls, page 16 in Geology Crafts for Kids), large samples of igneous, sedimentary (including one with fossils), and metamorphic rocks, table and chairs for Branigar. For Activity 1: sandwich materials for each student, one half used tube of toothpaste (or more), pencil, bar cookies. For Activity 2: pencils and paper, activity sheets for scavenger hunt, for Activity 3 boxes with rock specimens, geologist hand lenses, Rock Cycle chart. Greet students and introduce yourself. The ever-changing Earth, like you and me has past history, present and future. But the Earth s history is really, really old. Good explanation of how old the Earth is can be found on page 7 Geology Crafts for Kids. Show uncut apple. How is it like the Earth? Cut apple. Skin of apple is crust (Earth s crust is made up of rocks and is 5 30 miles thick in some places), fleshy part of apple is mantle (also made of rocks, but doesn t behave like rocks we see. It moves slowly with consistency of silly putty), and core of apple is like the earth s core. (made up of hot mass of metals). Instead of apple, may use Earth Balls page 16 from Geology Crafts for Kids. Teach or reinforce What is the Grand Canyon made of? Find out what students know about rocks. How do you think a rock is made? Are all rocks formed the same way? (Rocks are collections of mineral grains stuck together.) Why would anyone want to study rocks? (Great way to discover information about history of Earth.) Show students examples of three types of rocks igneous, sedimentary and metamorphic. (Use obvious specimens for grade 3 4). Include sedimentary rocks with fossils. Are all the rocks the same color? Same hardness? Same texture? How a rock is formed determines which rock type it belongs to. Depending on age of students and previous knowledge, docent may want to proceed with Activity 1. For grades 5 7 An Introduction to Grand Canyon Geology by Greer Price, pages 18 20, discusses the 3 rock types. Igneous rocks. Comes from Greek word for fire. What do you think makes fire rocks? Deep in Earth, so hot that rocks have melted. Pressure is so tremendous that melted rock (magma) will push up through Earth s crust, like tube of toothpaste. Sometimes volcano is created. As lava (magma which has reached earth s surface) cools, igneous rock is formed. Basalt is an example of quick cooling rock. All igneous rocks do not cool the same way, which is why they don t look alike. Ex: basalt, rhyolite, obsidian, granite Sedimentary rocks. Rocks on Earth s surface are constantly being broken (eroded) up by wind, water, and ice. Small pieces tumble down rivers and over time are pressed together into solid sedimentary rock. Some sedimentary rocks are cemented together by minerals dissolved in water. Most sedimentary rocks form under water and are often rich with

4 fossils. Ex: sandstone, limestone, conglomerate If most sedimentary rock forms under water, how does it turn into dry land? Over millions of years, sedimentary rock is pushed upward by rising magma or oceans just dry up. Metamorphic rocks. Comes from Greek word meaning change. How do you think a rock could be changed into something new? Metamorphic rocks form deep in Earth where high temperatures, great pressure and chemical reactions cause one type of rock to become another type. If you squeeze and heat a rock for a few million years, it can turn into a new kind of rock. Ex: limestone becomes the metamorphic rock marble, sandstone becomes quartzite, shale becomes slate. The metamorphic rock schist can form from shale, granite or volcanic rocks. Rock cycle (grade 7). Rock cycle is ongoing recycling process that has shaped the earth in the past and continues to shape it today. Igneous rocks might roll down mountain formed by volcano. As they roll, pieces of igneous rocks are broken and form sediments, which then are pressed and cemented together forming sedimentary rocks. Some of the sedimentary rocks on the very bottom get hot because of the extreme pressure form rocks above and they change into metamorphic rock. When metamorphic rock is buried deeper, it gets hotter and melts and once again may eventually be pushed up and out of a volcano. These changes are part of the rock cycle, which moves in such slow motion that geologists measure these movements in geologic time. To a geologist, a million years is just a blink of an eye. Predict from the rock cycle two different changes that a rock could undergo. ACTIVITIES Suggested activities Grade 3 & 4 Sedimentary Sandwich (sedimentary rock) from Earth Science for Every Kid. Each student makes own sedimentary sandwich, using following possible suggestions. Bottom slice of grainy, whole wheat bread will be the oldest sedimentary layer (made from flour, salt, sugar cemented by water) could represent sandstone, Layer of Nutella could represent mudstone, could have different bread layer, layer of shrimp in mayonnaise (Arthropods some of the earliest animals to swim in sea) could represent limestone with fossils. (Modify as hunger dictates.) Discuss: Sedimentary rocks formed from loose particles carried from one place to another and redeposited. Each layer can be distinguished by differences in color, texture and composition. The oldest layer is on the bottom and the youngest is on the top. The layers over time become compacted and cemented together. Squirt (igneous rock). Take half-empty tube of toothpaste and with the cap screwed on tight, force toothpaste toward capped end. Using a pencil point, make a hole in the tube near the cap and watch toothpaste flow down the side of the tube. Discuss how tremendous pressure within the Earth can force liquid rock called magma out of cracks in the Earth s surface. When liquid rock reaches Earth s surface, it is called lava. When you hold an igneous rock, you re holding piece of Earth s mantle be glad it s had time to cool off! Metamorphic Rocks (metamorphic rock) from Geology Crafts for Kids. Possibly pre make these bar cookies that, like metamorphic

5 rocks, are formed partly by pressure and heat. These bar cookies consist of layers of graham cracker crumbs, raisins, chopped nuts, chocolate chips, granola that are pressed with a measuring cup and then baked (pressure and heat!) Grades 3 7 Divide students into five or six groups. Have groups take turns engaging in two activities Scavenger hunt. Ask the first half of students to look around Geology gallery. Grade 3 6: Find one rock from each of the three rock types. Name it and describe its color and texture. Which of the rocks do you think you might find around the outside of your house? Grade 7: Find at least one rock from each of the three rock types. Classify each rock by grain, color, texture and be sure to identify its type. Grade 3 7: Try to answer the following questions: Why do you think there is only one metamorphic rock in the Gallery? Grade 5 7 Hint: Look at the Precambrian Origin of Life What is the name of the rock? Add your own questions or use the following as bonus questions to lengthen the tour. Grade 3 7: Find the shark s tooth in the gallery. Was it found in igneous, sedimentary or metamorphic rock? In what type of rock would you most likely find fossils? Why? Grade 3 7: What rock in the Geology gallery is like the Earth s core? (Meteorite) Hint: It weighs 400 pounds. Where did it come from? How old could it possibly be? Grade 3 4: Find a picture of the interior of the Earth. True or false The deeper you go in the Earth, the colder it becomes. Grade 7: What is an unconformity? How could rocks be missing? Grade 5 7: Find a fossil of a dinosaur that was discovered in the sedimentary Chinle Formation (mudstone). What did the reptile look like? What did the land look like then? Grade 3 7: Can you find a dinosaur track? What type of rock was it found in? How do you think the track was preserved? Grade 3 7: Find the igneous rocks. Although you wouldn t want to be hit by any of them, which one would probably hurt the most? (bomb) the least? (pumice) Grade 5 7: What is it that makes these volcanic rocks different? Grade 3 7: There is a dinosaur that was only found in Arizona. What was its name? Was its footprint found in igneous, sedimentary or metamorphic rock? Grade 3 7: What can scientists learn by studying rocks? Why is determining the age of rocks important to understanding the history of the Earth? Rock identification. Give three groups of students (second half of class) specimen boxes and hand lenses. For grades 3 5 have each rock type in its own box. For grades 6 7 mix samples and ask students to sort rocks into each of the

6 three rock types. What do you notice about the particles that make up the sedimentary rocks? (glued together). What do you notice about the crystals that make up the igneous rocks? (grown together) What do you notice about the metamorphic rocks? (rocks look distorted or stretched grains look melted together). How are the rocks similar? Have group pick their favorite rock and create a very short story about where the rock originated, what happened to it along its journey and what it might become some day. Grade 7 should identify environmental conditions and subsequent changes for their rock s journey (rock cycle). Share rock stories and answers to questions. Time Machine. (Grades 5 7) Divide into 5 groups and have each group select one of the following rock types found in the Grand Canyon: Vishnu Schist (sample of schist is next to meteorite. Make sure students see the Roots of Ancient Mountains pullout), Coconino Sandstone, Kaibab (limestone) Formation, Supai Group (mostly mudstone and sandstone), Tapeats Sandstone. Your group has the ability to be transported back in time to when your particular rock layer was deposited. Use information from the exhibits in the museum to write a paragraph to describe the environment that you find, life forms (if any), and the approximate period you traveled to. What s the most interesting part of your new environment? Would you be able to live there? Why or why not? Rock Cycle (Grade 7) The Earth is a very active place. There s a nonstop game going on to change all three types of rocks igneous, sedimentary, metamorphic into another type of rock. Rocks that were created deep in Earth s mantle, then raised slowly to the surface, and then destroyed by water and wind can be re-created again, and again, and again. Pick one rock type and describe its journey to another rock type. Look at Rock cycle chart and see if it fits your journey. POSSIBLE EXTENSION As students travel around Colorado Plateau, ask them to try to identify the type of rock they see. Which types of rocks are they most likely to observe? If they wanted to find fossils, what type of rock should they look for? (Please don t collect, but allow for others to enjoy.) CLEAN UP Return all specimen rock boxes and hand lenses to Owaki ARIZONA ACADEMIC STANDARDS SCIENCE Strand 1: Inquiry process Concept 1: Observations, Questions, and Hypotheses Grades 3 4: Observe, ask questions, and make predictions PO 1. Formulate a relevant question through observations that can be tested by an investigation Related Questions How do you think a rock is made? Are all rocks made the same way?

7 What can we learn by studying rocks? PO 4 (grade 4) Locate information related to an investigation. Grades 5 7: Formulate predictions, questions, or hypotheses based on observation. Locate appropriate resources PO 1. Formulate questions based on observations that lead to the development of a hypothesis Related Question In what type of rock (igneous, sedimentary or metamorphic) would you find fossils? Why? Concept 2: Scientific testing (investigating and modeling) Grades 3 4: Participate in planning and conducting investigations, and recording data PO 3. Conduct simple investigations (e.g. related to properties of rocks) in life, physical, and Earth and space sciences. Related Questions 1. Are all rocks the same color? Same hardness? Have the same texture? 2. Which rock type (igneous, sedimentary or metamorphic) has only one sample in the Geology Gallery? Why? 3. Group specimen rocks into categories: sedimentary, igneous and metamorphic Concept 3:Analysis and conclusion Grade6 7: Analyze and interpret data to explain correlations and results; formulate new questions. PO 5. Formulate a conclusion based on data analysis Related Question Predict from the rock cycle two different changes that a rock could undergo if left in its natural setting. Concept 4: Communication Grade 3: Communicate results of investigations PO 1. Communicate investigations and explanations using evidence and appropriate terminology PO 3. Communicate with other groups to describe the results of an investigation. Strand 6: Earth and Space Science Concept 1: Properties of Earth materials Grade 3: Identify the basic properties of Earth materials PO 1. Identify the layers of the earth Crust Mantle Core (inner and outer)

8 PO 2. Describe the different types of rocks and how they are formed Metamorphic Igneous Sedimentary PO 3. Classify rocks based on the following physical properties Color Texture Concept 1: Structure of the Earth Grade 5 7: Describe composition and interactions between the structure of the Earth and its atmosphere. PO 1 (grade 7): Classify rocks and minerals by the following observable properties: Grain Color Hardness Texture PO 2 (grade 7): Describe the properties and the composition of the following major layers of the Earth: Crust Mantle Core PO 4 (grade 7): Describe how the rock and fossil record show that environmental conditions have changed over geologic and recent time Concept 2: Earth s Processes and Systems Grade 7: Understand the processes acting on the Earth and their interaction with the Earth systems PO 1. Explain the rock cycle PO 2. Distinguish the components and characteristics of the rock cycle for the following types of rocks Igneous Metamorphic Sedimentary

9 ROCKS OF THE GRAND CANYON OVERVIEW FOR TEACHERS/PARENTS AGE/GRADE LEVEL DURATION GROUP SIZE LOCATION BACKGROUND ESSENTIAL QUESTIONS This program is appropriate for grades 3 7. Rock types are introduced in grade 3. Classification of rocks and minerals and the rock cycle are introduced in grade hours (grades 3 4) 2 hours (grades 5 7) 30 students plus one educator/chaperone for every six students Babbitt Reading Room and Geology Gallery This program should help students identify the three rock types the Earth is made of and to begin to understand that rocks are fascinating ways to discover information about their origin and that of the history of the Earth, as well. Most of the rock layers found at Grand Canyon are sedimentary, laid down over long periods of time by rivers and seas. A small amount of the sedimentary rock was deposited by desert winds. The oldest rock found at the bottom of the Canyon is metamorphic (rock formed by heat and pressure). Igneous rock, seen in the inner gorge and in the Western part of Grand Canyon, was formed by hot, molten rock called magma that cooled either below or on the Earth s surface (then called lava). The marvel of Grand Canyon is that its rock layers are so beautifully exposed. By the end of the end of the program, students should be able to answer the following question: 1. Where do rocks come from? How do rocks differ from each other? Are all rocks formed the same way? What are the three types of rock? 2. Which of the rock types would you expect to be most prevalent in the Grand Canyon? Why? 3. Why would anyone want to study rocks? (grades 3, 4, and 5) Why is determining the age of rocks important to understanding the history of the earth? (grades 6 and 7) KEY WORDS USED IN THE PROGRAM Crust Sedimentary Rock cycle (grade 7) Mantle Metamorphic Core Texture Igneous Fossil ARIZONA ACADEMIC STANDARDS ADDRESSED BY THIS PROGRAM SCIENCE Strand 1: Inquiry process Concept 1: Observations, Questions, and Hypotheses Grades 3 4: Observe, ask questions, and make predictions PO 1. Formulate a relevant question through observations that can be tested by an investigation

10 Related Questions 1. How do you think a rock is made? Are all rocks made the same way? 2. What can we learn by studying rocks? PO 4 (grade 4) Locate information related to an investigation. Grades 5 7: Formulate predictions, questions, or hypotheses based on observation. Locate appropriate resources PO 1. Formulate questions based on observations that lead to the development of a hypothesis Related Question In what type of rock (igneous, sedimentary or metamorphic) would you find fossils? Why? Concept 2: Scientific testing (investigating and modeling) Grades 3 4: Participate in planning and conducting investigations, and recording data PO 3. Conduct simple investigations (e.g. related to properties of rocks) in life, physical, and Earth and space sciences. Related Questions 1. Are all rocks the same color? Same hardness? Have the same texture? 2. Which rock type (igneous, sedimentary or metamorphic) has only one sample in the Geology Gallery? Why? 3. Group specimen rocks into categories: sedimentary, igneous and metamorphic Concept 3:Analysis and conclusion Grade6 7: Analyze and interpret data to explain correlations and results; formulate new questions. PO 5. Formulate a conclusion based on data analysis Related Question Predict from the rock cycle two different changes that a rock could undergo if left in its natural setting. Concept 4: Communication Grade 3: Communicate results of investigations PO 1. Communicate investigations and explanations using evidence and appropriate terminology PO 3. Communicate with other groups to describe the results of an investigation. Strand 6: Earth and Space Science Concept 1: Properties of Earth materials Grade 3: Identify the basic properties of Earth materials PO 1. Identify the layers of the earth

11 Crust Mantle Core (inner and outer) PO 2. Describe the different types of rocks and how they are formed Metamorphic Igneous Sedimentary PO 3. Classify rocks based on the following physical properties Color Texture Concept 1: Structure of the Earth Grade 5 7: Describe composition and interactions between the structure of the Earth and its atmosphere. PO 1 (grade 7): Classify rocks and minerals by the following observable properties: Grain Color Hardness Texture PO 2 (grade 7): Describe the properties and the composition of the following major layers of the Earth: Crust Mantle Core PO 4 (grade 7): Describe how the rock and fossil record show that environmental conditions have changed over geologic and recent time Concept 2: Earth s Processes and Systems Grade 7: Understand the processes acting on the Earth and their interaction with the Earth systems PO 1. Explain the rock cycle PO 2. Distinguish the components and characteristics of the rock cycle for the following types of rocks Igneous Metamorphic Sedimentary