ROCKS AND THE ROCK CYCLE POCKET GUIDE (MODIFIED FOR ADEED)

Transcription

1 ROCKS AND THE ROCK CYCLE POCKET GUIDE (MODIFIED FOR ADEED) Overview: Volcanic rock differs from other types of rock in important ways. In this activity, students learn about the three main rock types: igneous, sedimentary, and metamorphic. Students also will create a guide that describes the rock cycle. Objectives: The student will: describe the transitions between rock types that are part of the rock cycle; create a pocket guide that illustrates the rock cycle; and explain how different rock types are formed. Targeted Alaska Grade Level Expectations: Science [6, 7, 8] SA1.1 The student demonstrates an understanding of the processes of science by asking questions, predicting, observing, describing, measuring, classifying, making generalizations, inferring, and communicating. [6] SD1.1 The student demonstrates an understanding of geochemical cycles by exploring the rock cycle and its relationship to igneous, metamorphic, and sedimentary rocks. [7] SD2.1 The student demonstrates an understanding of the forces that shape Earth by identifying strategies (e.g., reforestation, dikes, wind breaks, off road activity guidelines) for minimizing erosion. Materials: Solid chocolate balls Sandwich-type cookies 8 x 10 sheets of paper Colored pencils or markers Samples of igneous (granite, obsidian), metamorphic (slate, gneiss), and sedimentary (sandstone, limestone) rocks. STUDENT INFORMATION SHEET: How to Make a Rock Cycle Pocket Guide STUDENT WORKSHEET: VISUAL AID: Rock Types VISUAL AID: Rock Cycle Activity Procedure: 1. Distribute a sandwich cookie and a chocolate ball to each student. Ask students to think about how these sweets are created (the chocolate is created by melting ingredients and pouring them into a mold, while the sandwich cookie is created by layering different substances). 2. Explain that there are three main types of rocks: igneous, sedimentary, and metamorphic. Use the Transparency: Rock Types to show the characteristics of the three rock types. Show the actual rock samples as each type is discussed. 3. Ask students which rock type might the chocolate represent (igneous: the chocolate is like hot magma that has cooled), and which type the sandwich cookie might represent (sedimentary). Ask students how these sweets could be used to represent metamorphic rock (if they were flattened, or compressed, they would represent metamorphic rock). 4. Explain that the three rock types are interrelated in what is referred to as the Rock Cycle. Use the Transparency: Rock Cycle to show the processes involved in rock formation and breakdown. Explain that all rocks turn into sediment through weathering. Thus, a rock can enter the rock cycle as sediment. Rocks can also enter the rock cycle as magma. Rocks can undergo many transitions. 5. Distribute the Student Information Sheet: How to Make a Rock Cycle Pocket Guide. Ask students to create

2 ROCKS AND THE ROCK CYCLE POCKET GUIDE their own guide to remind them of what the main characteristics of these rocks are, as well as how the rock cycle works. 6. Distribute the Student Worksheet: and ask students to complete the worksheet. If necessary, display the transparency again to help remind students about the characteristics of different rocks as students complete their rock cycle pocket guides. Answers: STUDENT WORKSHEET: 1. Answers may vary, but should include the idea that igneous rocks are formed from magma that is extruded from Earth or trapped under the surface. 2. Answers may vary, but should include the idea that sedimentary or igneous rocks are subjected to pressure or heat and changed. 3. Answers may vary, but should include the idea that existing material is broken down, layered, and compacted. 4. Weathering and compaction 5. Subjection to pressure and heat. 6. Melting and crystallizing

3 HOW TO MAKE A ROCK CYCLE POCKET GUIDE Background Information: Volcanic rocks represent only one of three main rock types: igneous, sedimentary, and metamorphic. All of these rock types are part of the rock cycle, a process where one type of rock transitions into another through processes such as melting, weathering or pressurizing. This activity explores the different rock types and the rock cycle. Procedure: 1. Fold the paper again along the dotted lines as illustrated below. 2. This will result in a booklet that opens in two directions. 3. Give the booklet a title on the front cover, such as My Rock Cycle Guide. 4. Open the booklet so that all three panels are showing. On the first panel, write Igneous. Illustrate this panel with symbols, words, drawings, etc., that represent igneous rock. 5. On the second panel, write Sedimentary. Illustrate this panel with symbols, words, drawings, etc., that represent sedimentary rock. 6. On the third panel, write Metamorphic. Illustrate this panel with symbols, words, drawings, etc., that represent metamorphic rock. 7. On the back of the booklet, draw the rock cycle, including the three types of rocks, magma, and sediment. Include arrows that show transitions between different rock types. 8. Label each arrow with the process associated with the transition. For example, the arrow pointing from metamorphic to igneous should be labeled melting. 9. Use this rock cycle pocket guide to help remember the three main types of rock and the processes of the rock cycle. 10. Complete the questions on the following page. fold along dotted line fold along dotted lines My Rock Cycle Guide igneous sedimentary metamorphic Rocks and Rock Cycle Pocket Guide

4 NAME: ROCKS AND THE ROCK CYCLE POCKET GUIDE Directions: Provide directions on how to complete the worksheet here. 1. Explain, in your own words, how igneous rocks are formed. 2. Explain, in your own words, how metamorphic rocks are formed. 3. Explain, in your own words, how sedimentary rocks are formed. 4. What are the processes that can cause igneous or metamorphic rock to turn into sedimentary rock? 5. What are the processes that can cause igneous or sedimentary rock to turn into metamorphic rock? 4. What are the processes that can cause metamorphic rock to turn into igneous rock?

5 ROCK TYPES Igneous Igneous rock is formed directly from magma. There are two types of igneous rocks, intrusive and extrusive. Intrusive igneous rocks are formed when magma is trapped within Earth. The magma cools slowly because of granite pumice obsidian the surrounding rock. These rocks are coarse grained. An example is granite. Extrusive igneous rocks, on the other hand, are formed when magma reaches the surface of Earth and cools quickly. Mineral crystals cannot grow very large during this rapid cooling, so the rocks are fine grained. Texture can vary. Examples are pumice and obsidian. Igneous rocks are the most common rocks found in Hawaiÿi. Sedimentary Sedimentary rock is formed from sediment pieces of other rocks that have broken into smaller particles from the action of wind, ice, or water. These particles are washed away and accumulate at sandstone shale limestone the bottom of rivers, lakes, streams, or oceans. Over time, layers stack up on top of each other. The layers are compressed and eventually turn into rock (lithify). Examples are sandstone, shale, and limestone. Some sedimentary rocks are formed from layers of mineral crystals or the remains of living material such as shells or plants. Metamorphic Metamorphic rocks are rocks that have changed into another type of rock. Metamorphic rocks can be formed from sedimentary, igneous, or other metamorphic rocks. Pressure or heat causes marble slate gneiss them to become compacted, changing them into something new. The grains in metamorphic rocks are often flattened. Sometimes the new rock looks very similar to the old rock, but sometimes the change is dramatic. Examples of metamorphic rocks are marble (metamorphosed limestone), slate (metamorphosed shale), and gneiss (from different rock types).

6 ROCK CYCLE Magma Metamorphic Rock Igenous Rock Sediment (sand, silt, clay) Sedimetary Rock Melting Crystalizing Weatherizing Metamorphosing (pressure, heat) Compacting and Cementing