Adriana Ocampo - Cookie Quarry

	www.iwaswondering.org © 2005 National Academy of Sciences
PRINT THE COOKIE QUARRY DATA SHEET TOO! You also need to print the Cookie Quarry Data Sheet for a full set of Science Lab instructions.

Adriana Ocampo is a planetary geologist who studies rocks and landforms on other planets and right here on Earth. Adriana and her husband were traveling in Belize when Adriana made an amazing discovery in a type of rock known as breccia. Trapped in the breccia were pieces of ejecta—material that results from the crash of an outer space object into Earth.

In this activity you'll bake cookies that look like breccia. Then you'll see if your friends can identify the ingredients, the way that geologists like Adriana identify the pieces in real breccia.


	3 eggs ½ cup butter 1 cup brown sugar, packed 1 cup white sugar 1 teaspoon vanilla 1 teaspoon white corn syrup 2 teaspoons baking powder 1½ cup peanut butter 4½ cup quick oats 1 cup chocolate chips 1 cup M&Ms Cookie sheet Measuring cups Measuring spoons Bowls Mixer Teaspoon Oven mitts or pot holders Cooling rack An adult Fellow scientists Paper Pens or pencils Cookie Quarry Data Sheet Cookie Quarry Rocks Cookie Quarry Journal

1. Print this activity.

Print this page, the Cookie Quarry Data Sheet, the Cookie Quarry Rocks page, and the Cookie Quarry Journal.

2. Make cookies.

Cream together eggs, butter, brown sugar, and white sugar
Add remaining ingredients and mix well
Spoon onto ungreased cookie sheet
Bake at 350° F for 12-15 minutes
Remove from the oven and let cool on a cooling rack

3. Have a cookie party.

Invite some friends and fellow scientists over to share cookies with you. Give each one a couple of cookies, a sheet of paper, and a pen or pencil. Tell them they will have to make a hypothesis, or guess the ingredients in the cookies, before they can actually eat the cookies.

4. Look for clues.

Ask your fellow scientists to break open one of their cookies. They should write down what ingredients they think you used to bake the cookies. When they're done, collect all the papers.

5. Analyze your data.

Use your friends' papers to fill in the Cookie Quarry Data Sheet. When you're done, compare their guesses to the actual ingredient list. Together, look at the Cookie Quarry Rocks printout and see which type of breccia most resembles your cookies.

6. Eat up!

Yum.

7. Fill in the Cookie Quarry Journal

We didn't expect you to do all the work before you ate! So have another cookie and fill in your journal. Then go outside and look for clues in some real rocks.

Certain types of rocks are likely to be found in specific areas of Earth.

Sedimentary rocks, such as shale, limestone, and breccia, make up 75% of the rocks found near the surface of Earth. Sedimentary rocks are formed when sediment, or small pieces of material like sand, soil, and mud become cemented together by pressure. The Grand Canyon is a great example of a sedimentary rock formation.

Igneous rocks are formed from magma, a hot, liquid mix of minerals found deep below the surface of the earth. Granite is an igneous rock.

Metamorphic rocks are formed when intense heat and pressure transform one type of rock into another, new type of rock. Schist and gneiss are both common types of metamorphic rock.

Breccia is a type of sedimentary rock that is formed from a composite of other angular rock fragments. It is named from a Latin word that means "broken." There are many different types of breccia, but they can all be identified by the big chunks of material found inside of them, just like your cookies! Check out the pictures below to learn more.

	Fault breccia is formed as the plates of Earth's crust scrape against one another, causing pieces of rock to break off, only to be cemented together again.
	Impact breccia is caused by the force of a comet or an asteroid striking the planet.
	Volcanic breccia contains lava and other volcanic materials that have been cemented together.
	Sometimes magma deep inside the Earth cools and becomes solid. When it pushes through the Earth's crust, it shatters other minerals, which become the components of shatter breccia.

When a scientist has finished her fieldwork, she always writes up her notes and analyzes her data. Write your analysis here, starting with a few simple questions.

What ingredients were your friends able to identify correctly?

What is similar about these ingredients?

What ingredients were your friends not able to identify just by looking at the cookies?

What is similar about these ingredients?

Why do you think some of the ingredients remained identifiable while others did not?

Did anything you learn surprise you?

Take a look at the pictures of breccia in the Cookie Quarry Data Sheet. Can you find the "ingredients" or different types of rock that make up the breccia? Which type of breccia do your cookies look the most like?

What else do you want to find out about rocks? Write it down here to keep a scientific record.

Rock Clues

Rocks tell stories of the Earth. Impact breccia is frequently analyzed by geologists because its presence helps them to know that a crater is nearby.

Go outside and check out the rocks that you find in your backyard for clues. Analyze them. What types of rocks do you find? What clues do they tell you about the terrain near you?