Rock Cycle Investigation

Probe: Is It a Rock. (Version 2) What is a rock Probe: Is It a Rock? (Version 2) What is a rock? How do you decide if something is a rock? Put an X next to the things that you think are rocks. Cement Block Dried Mud Hardened Lava Asphalt (Road Tar) Glass Piece of Clay Pot Coral Limestone Iron Ore Concrete Coal Brick Gravestone Marble Statue Granite

Exploration A Obtain chocolate (each a different color). Warning! Please do not eat the chocolate at this time. Using yours scissors, cut the chocolate into the different size pieces. Do this over a piece of paper. Make sure to keep the colors separated.

Exploration A Describe what you did to your chocloate in exploration A. What process in nature breaks down rocks? What are some forces in nature that cause this process to occur? What do we call the fragments of rocks left by this process?

Exploration B Once rock fragments (sediments) have been created, they are usually moved by some force of nature. In this exploration, you will act as this force.

Exploration B Obtain 2 pieces of wax paper. Place one color of your sediment onto the wax paper. Place it in the middle of the wax paper and have it take up an area of about one square inch. Place second color on top of the first color and continue this process with the third color.

Exploration B Describe what you did to your sediment pieces in Exploration B. What is the force that moves rock fragments called? What are some of the causes of this force?

Exploration B Draw and describe your sediments. The forces responsible for erosion cannot carry sediment forever. Eventually, the moving water, wind, or ice slows and the sediment is laid down somewhere. What process in nature involves the laying down of sediment?

Exploration B As time passes (millions of years), new sediment is laid down on top of older sediment. What is this process of layering sediment called? What forces could interfere with this process?

Exploration B Fold the four sides of the wax paper over the middle section of the wax paper where your starburst pieces are located. This will create a “wax paper package” where your starburst pieces are safely stored inside. Tape the package closed Label the outside of the wax paper with your name.

Exploration C At this point in the rock cycle, imagine layers upon layers of sediment being deposited and stratified over millions of years. Think about what is happening to the lower layers of sediment. The upper layers press down on the layers beneath them. The weight of the new layers further applies force to the layers beneath them, squeezing them tightly together. In this exploration, you will act as this force.

Exploration C Obtain two books for this exploration. Place your wax paper package between the two books. Apply pressure with your hands or sit on the books in order to compress the rock fragments for four minutes.

Exploration C Describe what you did to your sediment pieces in Exploration C. What do we call the process of smashing or compressing rock fragments?

Exploration C As you were smashing the sediment pieces, think about what is also happening. Watch as your teacher models this. What do the sediment pieces do? What do we call the process of rock sediment sticking together? Your teacher will explain what is happening in this process. Describe the process below.

Exploration C Once your rock has been mildly compressed, carefully open the wax paper package. Observe the new product.

Exploration C What observations can you make about your rock? What type of rock have we formed?

Exploration D The previous explorations demonstrated how rocks are eventually covered over by other layers of rock and subsequently, buried deeper into the earth. This part of the investigation will demonstrate what will happen next.

Exploration D Warm the “sedimentary rock” by rubbing your hands together and placing them on the package. Take turns and do this for a minute. Your teacher will instruct you when to stop. Next, place the wax paper package between the two books provided. Put pressure on the books. Continue to provide pressure for several minutes.

Exploration D Describe what you did to your “chocolate rock” in Exploration D. What is the purpose of applying heat for a minute? What is the purpose of placing the wax paper package between the books?

Exploration D Remove the books. Carefully open the wax paper package to examine your new rock. Describe your new rock. How is it different than the rock that was formed in exploration C? What type of rock have we formed?

Exploration E Your teacher will give you a cup for each person in your group. Divide your chocolate rock between the people in your group and place your pieces in your cup. Microwave your cup for 30 seconds at the most. While your system is running, set up the equipment for the next part of the lab. This involves filling an aluminum pie pan with ice.

Exploration E While it is still in the molten state, place the cups on top of the ice.

Exploration E Describe what you did to your “chocolate rock” in Exploration E. What happened to your “rock” after it had been in the microwave? What is the process of changing a material from the solid to liquid state?

Exploration E What is the name for molten rock? What is the difference between magma and lava?

Exploration E What happens to the molten chocolate after it has been on the ice for a few minutes? What is the process of molten material hardening over time? What type of rock is formed from cooled molten rock?

Exploration E You may now enjoy and eat your newly formed chocolate rock. Make sure to throw away all your trash into a trash can. Clean your area. Use disinfecting wipes when you done eating.

Review of Explorations A – E Using information from explorations A through E, compare our model of rock formation with the processes that occur in the natural world. Use the following word bank: Cementation (Lithification), Compaction, Cooling, Deposition, Erosion, Igneous Rock, Heat, Pressure, Magma/Lava, Metamorphic Rock, Melting, Sediment, Sedimentary Rock, Stratification, and Weathering.

Actual Process/Product Model Process Actual Process/Product Cutting the chocolate into small pieces with scissors Small pieces of chocolate Moving pieces to wax paper Placing pieces onto wax paper Layering pieces Hand Pressing the layers of pieces with books Process of pieces sticking together Type of Rock Formed due to processes above Placing hands on the rock for a minute Crushing rock with books Type of rock formed from being crushed Microwaving pieces Molten chocolate Trays with ice Type of rock formed after microwave and in ice trays