Last updated: November 7, 2018
- Grade Level:
- Upper Elementary: Third Grade through Fifth Grade
- Lesson Duration:
- 30 Minutes
- State Standards:
- ● Utah State Standard 3: Objective 1d, 2
● Utah State Standard 2: Objective 3
- Thinking Skills:
- Remembering: Recalling or recognizing information ideas, and principles. Understanding: Understand the main idea of material heard, viewed, or read. Interpret or summarize the ideas in own words. Applying: Apply an abstract idea in a concrete situation to solve a problem or relate it to a prior experience. Analyzing: Break down a concept or idea into parts and show the relationships among the parts. Creating: Bring together parts (elements, compounds) of knowledge to form a whole and build relationships for NEW situations. Evaluating: Make informed judgements about the value of ideas or materials. Use standards and criteria to support opinions and views.
What geologic processes created the landscape of shapes and colors we see in the cliffs at Cedar Breaks and Bryce Canyon?
Students will understand the basic properties of rocks, the formation of soils and the needs of plants provided by soil. Classify common rocks found in Utah as sedimentary, igneous and metamorphic. Explain how the processes of weathering and erosion change and move materials that become soil. Identify the processes of weathering that break down rocks (water movement, freezing, plant growth and wind.) Distinguish between weathering and erosion. Model the processes that leads to soil.
- Download and Read: Cedar Breaks Geology Brochure
- Materials: (Provided by a Cedar Breaks Ranger for Scheduled Field Trips.)
Several pieces of rock from the Claron formation showing a variety of color and composition, limestone, sandstone etc.
Small plastic containers with examples of different colors and textures of sediments that form the Claron formation.
- Map of Western States with Lake Claron area outlined.
- Foam model of a normal fault.
Step 1 - Engage (5 min):
Have students gather around and stand in a group out on Point Supreme. Introduce yourself and welcome students to Cedar Breaks National Monument.
Explain that Cedar Breaks National Monument was designated a National Monument to preserve and protect this beautiful canyon that we call the Cedar Breaks amphitheater. Explain that the layers, shapes and colors are unique to this area and tell a story of the Earth’s geologic history.
Ask "Does every one know what geology means?" (The study of rocks and minerals. The study of landforms and the Earth’s history.)
Hold up examples of a few different types of sedimentary rock from the Claron Formation. Ask "What is this rock made of? How did it form? How is it changing?"
Step 2 - Explore (5-10 min)
- Before giving answers to the questions above, have students get a good look at park's amphitheater.
- Let students know that in this lesson you will be teaching them about the process that formed the amphitheater and that they will get a chance to observe and draw parts the amphitheater.
- Geologic formations like the ones at Cedar Breaks and Bryce draw the attention of both scientists and artists - they pay at close attention to detail. Give students about 5 minutes to take a close look at the amphitheater, enjoy the view and notice details. Make sure they stay with your chaperone group and spread out along the railing so everyone has a clear spot to observe the view.
- Encourage students to look silently for at least minute or two. Circulate around the group while they look and after a few minutes ask students what they see in the rocks, have chaperones do the same.
- Choose to use your artist’s perspective or your scientist’s perspective as you look. Do you thing there is a difference?
- Notice what draws your eye and why? Is it a particular color or color combination? Are certain shapes interesting or beautiful you?
- If you were going to draw something you saw in the amphitheater what would you draw?
- What questions come to mind as you look at the amphitheater? Be ready to share what you noticed about the amphitheater with the class.
Step 3 - Explain (20 min)
Once students have taken a good long look call them back to the seating area. Have them sit in a group and give you their attention.
Call on a few students to share their answers to some of the questions above.
Wrap up sharing time by asking students to consider how these layers and shapes of the amphitheater could have formed.
Geologists have been studying the layers of rocks here at Cedar Breaks for decades. By making careful observations of the physical and chemical properties of each layer geologists have figured out how this amphitheater formed. The story starts about 65 million years ago. That is about the time on Earth when the dinosaurs went extinct. At that time the planet wasn’t that much different than how it is today. Although they were somewhat different than what we see around us now, there were plants and animals including small mammals, birds, reptiles and insects.
But the landscape right here was actually very different. Instead of this big cliff where you can now look down and see Cedar City, the land was flat. Out in the distance there were mountains, hills and higher areas all around. This part of Utah was a low spot in the landscape where all the water ran down the mountainsides and collected into a huge lake called Lake Claron. (Show map of western states with lake Claron outlined.)
Every time it rained the rain wore down or weathered some of the rocks in the mountains and brought the particles of sand and mud down from the hillsides into the bottom of the lake. The process of pieces of rock and sediment moving across the landscape is called erosion. (Show different sediment samples to the students and explain the word sediment)
This process continued for millions of years and during the different time periods different types of sediments came into the lake bottom and got laid down one on top of the other. (Show the jar with layers of different sediments.) Some layers were sandier, others were muddier and all of them had some amount of a rock called limestone. (Show and pass around different sedimentary rock examples and white limestone).
Overtime, the surrounding mountains eroded away and the climate got very dry. Lake Claron dried up entirely leaving the layers of sediment hidden under the ground.
Many millions of years more passed and a time of great volcanic activity started to erupt far away- almost 100 miles away! The volcanoes were so big and powerful that when they erupted hot ash came flying across the landscape and laid down in a greyish layer over the top of all the lake sediments. (Point out the ashy colored layer on top of the Claron formation). Overtime all these sediments and layers solidified and turned into rock layer. (Show and pass around some pieces of the Isom formation.)
Step 4 - Elaborate
Finally, as we come to the time in our planet’s history when people lived here, the land to the west of us started to move because of a huge crack in the earth’s crust called a fault. (Show the model of a normal fault) Slowly but surely as the land moved the layers that had been laid down in Lake Claron millions of years earlier became exposed.
Then the water and frost of winter began to carve the shapes in the canyon you see here. (Explain the process of frost wedging, chemical and physical weathering and the differential weather of layers that results in fins, arches and oddly shaped hoodoos.)
Step 5 - Evaluate and Conclude (10 min)
Imagine if any one of these events didn’t occur, or if some of the process that created the Claron Formation and Cedar Breaks happened at a different time or in a different order?
For example, what if the climate had been very dry 65 to 30 million years ago and Lake Claron didn’t exist for as long a period of time?
What if the Hurricane Fault wasn’t here?
What if the super volcanoes that brought in the ash erupted after the Hurricane fault moved and dropped the Basin and Range zone down and away from the higher Cedar Breaks area?
Have students consider how some of these “what if” scenarios would effects the landscape they are looking at right now.
Close by allowing students time to ask questions and then to draw a part of the Cedar Breaks amphitheater in their journals. Encourage them to label their drawings with some of the terms from the lesson.
Erosion - The wearing away and movement of earth materials by gravity, wind, water and ice.
Faults - A fracture or fracture zone in rock along which movement has occurred. When movement occurs, the vibrations produced are earthquakes.
Uplift - A structurally high area of Earth's crust. Formed by movements that bend the crust upward into a structure, or can be caused by subsidence of adjacent lands.
Volcano - A vent in Earth's surface through which molten rock and gases escape. The term also refers to deposits of ash and lava that accumulate around this vent.
Weathering - The breakdown of rocks at the Earth's surface, by the action of rainwater, extremes of temperature, and biological activity.
Deposition - the laying down of sediment carried by wind, water, or ice. Sediment can be transported as pebbles, sand & mud, or as salts dissolved in water. Salts may later be deposited by organic activity (e.g. as sea-shells) or by evaporation.