This self-guided field trip program allows teachers to use Curecanti National Recreation Area as their classroom for lessons about geology, plate tectonics, erosion, and conservation. You and your students will take a hike along the Dillon Pinnacles Trail and stop for interactive lessons along the way.
Park Rules & Safety
Safety
Be prepared for high-elevation desert hiking. Wear a hat and sunscreen. Carry a full water bottle. Water is not available along the trail. There is limited shade along the trail. Wear sturdy shoes with good tread, such as hiking boots or sneakers. Be aware of quickly changing weather conditions and be prepared to change your plan.
Park Rules and Field Trip Guidelines
Stay on the trail. The NPS protects all habitat, including fragile soils and plants along the trail. Do your part by staying on the trail.
Stay with your group.
Stay at least one body length away from the canyon edge.
Never throw or kick rocks over the edge of the canyon. There are hikers below.
Carry out all trash and be mindful of wind causing accidental littering.
Do not approach, feed, or yell at wildlife.
You may pick up rocks to look at them but put them back where you found them. Taking anything home from the park is illegal.
Use a soft voice. Visitors want to enjoy natural sounds, not students screaming.
Restrooms
There are two vault toilets at the trailhead, but no bathrooms along the trail. There are limited opportunities for hikers to "use the trees," if necessary.
Park Ranger guides students through what to bring and how to prepare for a field trip to Black Canyon of the Gunnison National Park.
Duration:
2 minutes, 3 seconds
Dillon Pinnacles Geology Field Trip
Suggested Length: 3.5 Hours (including lunch)
Education Standard: See end of lesson plan for suggested Colorado Department of Education alignment.
Overview: Students explore the geologic events that formed and the forces that continue to sculpt the Black Canyon of the Gunnison. Students discover how Paleo-environments reveal clues about the past and help predict future landscapes.
Subjects: Types of Rocks, Rock Layers, and Erosion
Objectives: By the end of the program students will be able to:
Identify types of resources national parks protect.
Name the three major rock types.
Describe the basic geologic processes that formed (volcanism, deposition, and erosion) the Dillon Pinnacles.
Materials:
Metamorphic (schist), sedimentary (sandstone), and igneous (pegmatite) rock samples
Laminated photograph identifying rock layers in Curecanti
Binoculars for close-up look at Dillon Pinnacles
Small whiteboard and whiteboard markers
Erosion Activity (Laminates: overview, weathering, erosion, and deposition and 11 processes)
“Interview with a Rock” reflection sheets and colored pencils
Sample Itinerary:
10:00 AM – 1:30 PM
Location
Content
Parking Lot
Bus arrives, students use restrooms. Waiting game: park/not a park.
Trailhead
Intro and plan. Safety message, we will have lunch on trail, class rules. What is geology?
Dinosaur Sign
Introduce big question: how did pinnacles form? Overview of 3 rock types. Metamorphic dance, talk about Black Canyon. Which rock type do we find fossils in?
Drainage
Along the trail, point out different rock types and do sedimentary dance. Fossils tell us about past environments. How can we know how old rocks are?
Ponderosa
Igneous dance. Volcanoes! ~30 million years ago, lava flows, welded tuff, on top of sedimentary. Law of superposition/pancakes/dirty laundry. Water break. Let's go get a better view of the youngest rocks.
Top of Mesa
Lunch, Blue Mesa, dams, drought. Gunnison River revealed these rocks. What else has changed the landscape over time?
Ponderosa
Weathering/erosion/deposition – vote with your feet activity. What will this area look like in 1 million years?
Dinosaur Sign/Shady Spot
Review pinnacle formation. Reflection activity – find a quiet
spot, look around. Write or draw what this area will look like in
1 year, 100 years, 1 million years. Share out. NPS protects this area for all of us to enjoy, but that doesn’t mean it doesn’t change.
Parking Lot
Bathrooms and load bus. Smile & wave.
Procedure
I. WELCOME, PLAN, & SAFETY (10 minutes) [Fishing Area]
Welcome the group to Curecanti NRA and introduce group leaders. Provide the plan—we will walk for approximately 2-3 miles round trip with stops along the way to explain the geologic history of Dillon Pinnacles. We will be gone for about 3 hours. The only bathrooms are at the trailhead. We will stop for lunch partway through our hike.
Explain that they are in an outdoor “classroom,” and that classroom rules apply. Have the students tell you their classroom rules. Make sure that raising hands before speaking and a way to call the group’s attention are covered (ex. “Class-Class” -“Yes-Yes”). Students should be divided into groups with a chaperone. Chaperones are expected to manage behavior, assist with activities, and stay with their student groups. We want students to have fun and learn about this place, but more importantly, we need them to get back on the bus in the same shape they came off the bus. Safety rules include: stay on the trail, walk between the ranger and an adult chaperone at the end of the line, don’t approach wildlife, and everything stays in the park.
Transition: Why is everything in a national park a “leaverite—leave ‘er right there?” What do national parks protect?
The National Park Service arrowhead logo.
NPS
II. INTRODUCTION TO NPS (15 minutes) [Trailhead]
The mission of the National Park Service is to leave places “unimpaired for the enjoyment of future generations.” How does the NPS do this? Show the NPS arrowhead.
Ask students what the objects on the arrowhead represent—these are the types of resources parks protect. (The arrowhead symbolizes ancient and modern human history of our country; the tree stands for plants, trees, flowers; the lake reminds us that all living things need natural resources like pure air, clean water, and dark skies; the bison represents all wildlife; and the mountain represents beautiful scenery, geologic features, and recreational opportunities.) Discuss the National Park Service, highlighting different types of parks and why parks are important. Ask students what types of resources they think Curecanti NRA protects.
Curecanti National Recreation Area exemplifies humans' ability to drastically alter
landscapes. It encompasses three dams built in the 60’s and 70’s for hydroelectric power and water storage, as well as a diversion tunnel built in 1912 to funnel water to the dry Uncompaghre Valley. The reservoirs created by the dams provide recreational opportunities for anglers, boaters, hikers, and campers. The recreation area also protects geologic features like the Dillon Pinnacles and Curecanti Needle and is home to badgers, beavers, Gunnison sage grouse, elk, deer, eagles, and both native and non-native fish species.
Transition: Curecanti NRA protects these animals as well as a geologic feature—the Dillon Pinnacles. Have students turn to a neighbor and come up with a definition of geology (A science that studies the history of the earth as it is recorded in rocks). Allow a couple of students to share their definitions. We are going to learn about millions of years of geologic processes that have happened right here at Dillon Pinnacles. As we walk the trail, make some observations about the rocks we see here. Ask for their observations when you stop.
An image of Dillon Pinnacles with different rock layers labeled: Welded Tuff at the top, then West Elk Breccia, Mancos Shale, Dakota Sandstone, and the Morrison Formation.
NPS
III. DEPOSITION (60 minutes) [Several stops along trail]
Today we are going to learn about the geologic processes that, over millions of years, formed the Pinnacles and the surrounding area. Geologists group rocks into three major rock types. Can anyone name them?
Metamorphic rocks (show sample of schist 1) are generally formed underground under intense heat and pressure. We have metamorphic rocks that are over 1.8 billion years old in the Black Canyon, down below the reservoir surface level. In order to remember how metamorphic rocks are formed, we can learn the following hand motions: “heat”—fan your face and “pressure”—push down toward the ground. Repeat these motions several times and tell the students they are going to be quizzed later.
Sedimentary rocks (show sample of sandstone 2) are formed by rocks being broken down into little pieces and then carried somewhere else by wind or water, deposited, and compacted over a long period of time. We have three sedimentary layers here (show image 3 with the rock layers identified). The Morrison Formation, the layer we are standing in, was formed 145 million years ago in a broad flood plain and is composed of sandstone and shale layers. One of the ways we know that this layer was formed in a terrestrial (land) environment rather than an aquatic (water) one is that we find dinosaur fossils in this layer. Refer to the dinosaur sign to show which species of dinosaurs lived here. We know that the Dakota Sandstone layer—105 million years old--was also mostly a terrestrial environment because we find petrified wood (show sample) of sequoia and magnolia trees. The Mancos Shale layer—80 million years old--was formed in an aquatic environment; we find mollusk, shark, and ammonite fossils in this layer. In order to remember how sedimentary rocks are formed, we use our hands to form “layer upon layer upon layer”—act like you are layering your forearms on top of each other.
Igneous rocks, on the other hand, are formed by solidified magma. Intrusive igneous rocks are formed when the magma solidifies underground. We have good examples of intrusive igneous rocks in the Black Canyon in the form of pegmatite (show sample 3). Extrusive igneous rocks are formed when magma comes to the surface in the form of lava or ash. They can either blast or ooze out in the form of lava. We have two types of extrusive igneous rocks here, West Elk Breccia (32 million years old), formed by volcanic mudflows, and Blue Mesa Welded Tuff (28 million years old), formed by compacted volcanic ash. These two rock types are technically “igneous sedimentary,” because they are igneous in origin, but sedimentary when they are deposited, compacted, and hardened. We can remember how igneous rocks formed by hand motions that show “flow”—act like your hands are flowing, then “cool”—freeze your hands in place. Review the concepts by asking students to demonstrate the hand motions for each of the rock types.
Explain that geologists use the Principle of Superposition to age rock layers. This is also called the “Principle of Pancakes.” If we made a pancake breakfast for the group, we would need to make pancakes in advance. We would have to stack them up on a plate before they showed up for breakfast. Where are the oldest pancakes on the stack—the bottom or the top? The same is true for rock layers. The oldest rocks are on the bottom and the youngest rocks are on the top. Which layer here is the oldest? The youngest?
Transition: We now know the Dillon Pinnacles are made up of igneous rocks (West Elk Breccia/ Welded Tuff) from ancient volcanoes but the pinnacles were not always the shape they are today, what forces do you think shaped the pinnacles into the spires we see today?
A world map with tectonic plates labeled by name and plate boundary type.
Optional 4th & 5th Grade Activity: Uplift & Plate Tectonics Essential Question: How did the rocks we see today move to the earth’s surface?
We learned that the metamorphic and igneous rocks that make up Black Canyon were formed 25 miles under the surface of the earth. Today, we see these rocks on the surface. What earth process is powerful enough to push these rocks up to the surface?
Plate tectonics is the process by which the plates that make up the earth’s crust move over time. (Image 4) The movement is driven by the convection currents in the earth’s mantle. These currents move the plates about 1 inch per year, about as fast as your fingernails grow. As the plates move, the different interactions at plate boundaries cause different landforms.
Boundary types:
convergent boundary (push into each other, pushing up mountains or volcanoes)
divergent boundary (two plates pull apart, new rock may form between)
transform boundary (plates slide past each other, friction may cause earthquakes)
Activity:
When you call out one of the plate boundary types, students must get into groups to act out the process.
Convergent boundary – 2 students raise their arms and push against each other, over their heads
Divergent boundary – 3 students. Two pull apart, while the third (the magma!) emerges between the plates.
Transform boundary – 4 students. Pairs, side-by-side, slowly move past each other laterally. Bonus points for demonstrating an earthquake.
Dillon Pinnacles, viewed across Blue Mesa.
NPS
IV. LUNCH (30 minutes)
V. EROSION (60 minutes)
Take a look at the Pinnacles. What do you think is happening to the breccia?
Weathering and erosion are responsible for creating Black Canyon, side canyons, and the Dillon Pinnacles. Weathering is rock material being broken down into smaller pieces by physical, chemical, or biological processes (show image 5, located in the erosion activity folder). Erosion is the movement of these smaller pieces of sediment or soil from one location to another (show image 6). Deposition is when that material is left behind and accumulates in layers (show image 7). Weathering, erosion, and deposition work together to change landscapes and recycle rock material around the planet (show overview laminate).
Activity—Erosion “Vote with your Feet”
We are going to test your understanding of weathering, erosion, and deposition. Pass out the weathering, erosion, and deposition card to three chaperones and have them stand in separate locations. Show a card to the group and each student has to decide whether the process shown is weathering, erosion, or deposition. Some processes may have more than one answer. Students need to “vote with their feet” for which chaperone has the card that best defines the process shown. Once students are all standing next to a chaperone, share the right answer(s) for that card. Hold up the card with the hiker last.
Transition: Today we’ve learned about many different types of rocks and how they can change and shape the landscape around us. Now is your time to find one special rock that you are going to interview about its life when we get to our next stop.
An aerial view of the Blue Mesa Dam in 1967.
NPS/J. Carpenter
Optional 5th Grade Activity: Effects of Human Activities on Dillon Pinnacles Geology (15 minutes)
(5th Grade Earth Science Standard 5. Societal activities have had major effects on land, ocean, atmosphere and even outer space)
Essential Question: In what ways are human activities influencing the process of erosion at Black Canyon?
While it can feel like Black Canyon was made by geologic processes much larger than people, human activities are affecting the canyon today. Brainstorm with your class what human activities may affect Black Canyon’s geology. Some human activities are directly influencing erosion (hiking off trail), or indirectly (human-caused climate change causing drought, less snow, warmer winters, etc.).
Divide your class into four groups. Give each group one human activity from the list to discuss how it may affect Black Canyon and the erosional processes we’ve learned about today.
Dams -
How do dams affect the process of downcutting and erosion?
Background: The dams upstream of Black Canyon on the Gunnison River were designed and built to hold water in case of drought, supplying water for agriculture, power, and other human uses. Dams prevent flooding by managing how much water moves through the river. You’ve learned that Black Canyon was carved by the river, especially when the river used to swell with spring runoff. The dams prevent large spring runoff flows in the river, instead releasing water in a more constant flow throughout the year.
Warmer Winters/freeze-thaw erosion -
How does warmer winter weather affect erosion at Black Canyon?
Background: Human-caused climate change is causing warmer, drier, and shorter winter seasons.
Drought -
In what ways is drought affecting erosion at Black Canyon?
Background: Climate change is causing warmer and drier conditions. Over many years, these conditions lead to significant drought.
More info: https://www.drought.gov/states/colorado/county/montrose
Hiking off Trail/Human-caused erosion -
How are people affecting erosion processes at Black Canyon?
Background: When people hike off trail, they can speed up erosion processes by kicking rocks. Many footsteps in the same place can also kill grasses and plants, loosening their roots that hold soil in place. Then when rains come, the trail may erode more quickly than before.
Have students share what they discussed about human effects on erosion at Black Canyon.
VI. REFLECTION: INTERVIEW WITH A ROCK or REFLECTION (20 minutes) 2nd/3rd Grade: Pass out the “Interview with a Rock” worksheets. Explain that each student will find a place to sit alone with a special rock. It may be a rock they can pick up, or it might be a huge rock that they sit on. Answer the questions on the worksheet. Allow students time to answer the questions. Gather together in the large group and have students share what their rocks “told” them.
4th/5th/6th Grade: Pass out the student reflection worksheets. Encourage students to find a spot to sit and think about what they’ve seen and learned about today. How has the landscape changed over time? What will it look like in the future? If there is time, review the activities they learned today. Test them on the rock type hand motions and the plate boundary actions.
VII. CONCLUSION (15 minutes)
The Dillon Pinnacles and the surrounding environments took millions of years to form and are still in the process of changing through the forces of weathering, erosion, and deposition. In another million years, do you think that the Pinnacles will look the same? Will the dam, reservoir, or roads still look the same? Will the same plants and animals be here? The answer to these questions really depend on you. You are the next generation of stewards of our National Parks tasked with leaving these places “unimpaired for the enjoyment of future generations.” What can you do to protect and preserve Dillon Pinnacles and other national parks (stay on trails, don’t litter, keep wildlife wild, bring your family and friends to visit the parks)? Thank you for learning with us, and come visit again!
Vocabulary
Geology: The study of the earth by examining rocks, minerals, and landforms as clues to the past
Igneous: Igneous rock is formed through the cooling and solidification of magma or lava
Metamorphic: Rock that has undergone transformation through heat and pressure
Sedimentary: Rock that is formed from mechanical weathering debris.
Erosion: The movement of sediment or soil from one location to another
Deposition: When rock or sediment is left behind from erosion and accumulates in layers
Weathering: Rock material breaking down into smaller pieces by physical, chemical, or biological processes
Colorado Dept. of Education Standards Alignment & Teaching Notes
CDE Grade 2: Standard 3. Earth and Space Science Wind and water can change the shape of the land; models can show the shape and these changes to the land.
CDE Grade 4: Earth & Space Science Standard 3.1: Earth has changed over time. Students can identify evidence from patterns in rock formations and fossils in rock layers to support an explanation for changes in a landscape over time. Students can answer the question: How can water, ice, wind and vegetation change the land?
CDE Grade 5th: Earth & Space Science Standard 3.5. Societal activities have had major effects on land, ocean, atmosphere and even outer space
