The Rock Cycle By Kathy Payne

Objectives Construct a model of the rock cycle Diagram the model of a rock cycle Draw conclusions

Engage How do rocks form? How long does it take rocks to form? Where do rocks come from? Are rocks forming right now? Why don’t all rocks look the same?

These questions and more can be answered by learning about a cycle in nature called… Since the cycle takes millions of years to occur, we will have to study a model to help us understand what happens. The Rock Cycle

MaterialsCrayons Paper plates Wax paper (2 sheets) Plastic knife –WARNING!!! The blade can cut skin, so be very careful. Card board Foil Clothes pin Chart paper Science journal

Explore Use a pencil sharpener to shave the crayons into a small cup. By breaking the crayons into smaller pieces, we modeled the process called… weathering. Place one pinch of each color in a pile on Plate 1. The pieces of crayon represent products called… sediments.

Move one color of the crayon pieces to the center of a piece of wax paper. Move one color of the crayon pieces to the center of a piece of wax paper. Make a pile that covers about 6 cm by 6 cm in area. Make a pile that covers about 6 cm by 6 cm in area. –By moving the sediments to a new location, you are modeling the process called… erosion. Add a new layer of crayons on top of the pile. –By laying down the sediments, you are modeling the process called… deposition.

Cover the pile with another sheet of wax paper. Carefully place the wax paper & crayons between two pieces of cardboards. Press on the cardboard to apply even, vertical pressure. –Y–Y–Y–You are modeling the pressure that is applied to the sediments after they are buried inside the Earth.

Remove the cardboards. Carefully remove the wax paper from the crayon sandwich. Place a small amount of the material in Plate 2. –The product represents a type of rock that is called… Sedimentary rock … because it is made of sediments. because it is made of sediments.

Replace the wax paper on the crayon sandwich and carefully place inside a book. Place the book on the floor and have someone stand on it for 1 minute applying even greater pressure than before. With the pressure, friction is creating some heat along with the heat from Earth. –You are now modeling the pressure that is applied when rocks are buried at greater depths inside the Earth.

Carefully remove the crayon sandwich from the book. Remove the top wax paper. Place a small piece of the crayon sandwich in Plate 3. –The product represents a type of rock that is called… Metamorphic Rock which means “to change”.

Crimp the edges of a piece of aluminum foil to make a holder (boat). Place the remainder of the crayon sandwich on the aluminum foil without the wax paper. Use a clothes pin as a handle. Follow the next directions carefully.

WARNING!!!… Hot plates are hot!!! Each group will bring their item to be placed on the hotplate. While the other groups are observing, you are to answer the following questions in your journal based on what you have observed so far during the experiment.

Journal Writing How do rocks form? How long does it take rocks to form? Where do rocks come from? Are rocks forming right now? Why don’t all rocks look the same?

The heat from the hot plate represents the great temperatures that are found deep inside the Earth. The melted crayons represent a product of melted rock material called… magma or lava.

Allow the melted material to cool and harden. Carefully peel off the aluminum foil. Place the material in Plate 4. The product represents a type of rock that is called… Igneous Rock which means “fire”.

Explain Place your four plates in a circular shape in the order of their numbers. Draw four circles on your chart paper to represent the plates.

In each circle draw, color and label the products that are on the plate located at that position. Sediments Sedimentary Rock Metamorphic Rock Igneous Rock Connect the drawing with arrows to show a continuous recycling of matter.

Using the diagram of the Rock Cycle, we will label the arrows to show the process that causes one type of rock to change into another type of rock. Then we will add the other arrows that show how rocks may change without going through entire cycle. Title your drawing on the chart paper.

Sediments

Sedimentary Rock

Metamorphic Rock

Igneous Rock