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National Park Service U.S. Department of the Interior

Zion National Park

Landscapes: Past, Present, and Future Exploring How Landscapes Change Over Millions of Years

NPS/MARC NEIDIG Contents

Introduction 2

Core Connections 2

Background 2

Activities Landscapes: Past 4 Landscapes: Present 6 Landscapes: Future 8

Glossary 9

References 11 Introduction

This guide contains background information about how geologic processes and changes over millions of years continually shape the landscape, and directions for three activities that will help students better understand how these processes are still at work in . This guide is specifically designed for fifth grade classrooms, but the activities can be modified for students at

NPS/BRYANNA PLOG other levels.

Theme Zion has spectacular geology. The arid climate The ’s surface is a dynamic system and sparse vegetation expose bare and that changes with the activity of volcanoes, reveal the park’s geologic history. Evidence earthquakes, , and other geologic of deposition (sedimentation), lithification, processes. uplift, , erosion, tectonics, and volcanic activity make the park a showcase for Focus changing landscapes. The activities focus on relationship between long-term geologic processes and changes on Deposition (Sedimentation) NPS/CAITLIN CECI the Earth’s surface that have happened in the was a relatively basin past, that are still occurring today, and will near sea level 275 million years ago, near the continue to occur in the future. of Pangaea, the land area believed to have once connected nearly all of the earth’s Activities landmasses together. As sands, gravels, and muds eroded from surrounding , Landscapes: Past streams carried these materials into the Students will explore what the area basin and deposited them in layers. The sheer surrounding Zion might have been like during weight of these accumulated layers caused past geologic times when each layer was the basin to sink, so that the top surface formed. By creating posters, the NPS/ADRIENNE FITZGERALD always remained near sea level. As the land students depict Zion during past geologic Today’s rocks in Zion National rose and fell and as the climate changed, the Park are the product of millions times and compare with the park today. of years of geologic processes depositional environment fluctuated from and different environments. shallow seas to coastal to a massive Landscapes: Present of windblown sand. This process of Using a topographic map of Zion, students sedimentation continued until over 10,000 Core Connections identify geological features (e.g., valleys, feet of material accumulated. , , ) that are present in Utah Core Curriculum Zion today. Lithification Fifth Grade Science Mineral-laden waters slowly filtered through the compacted sediments. Standard 2: Students will Landscapes: Future understand that volcanoes, During this activity students predict future Iron oxide, calcium carbonate, and silica earthquakes, uplift, acted as cementing agents, and with pressure weathering, and erosion changes to the landscape of southwestern from overlying layers over long periods of reshape Earth’s surface. Utah in 100 million years. time, transformed the deposits into stone. Objective 1: Describe how Ancient seabeds became ; mud and weathering and erosion Background clay became mudstones and ; and change Earth’s surface. sand and sand became . Each Zion National Park is located along the edge layer originated from a distinct source and so Objective 2: Explain how of a region called the . Uplift, volcanoes, earthquakes, and differs in thickness, mineral content, color, uplift affect Earth’s surface. tilting, and the erosion of rock layers formed and eroded appearance. a feature called the Grand Staircase, a series Objective 3: Relate the building of colorful cliffs stretching between Bryce Tectonics and Uplift up and breaking down of , Zion, and the Grand Canyon. Earth’s surface over time to the In an area from Zion to the Rocky Mountains, various physical land features. tectonic forces deep within the Earth

Zion National Park, 2015 Landscapes: Past, Prsent and Future 2 pushed the surface up creating the Colorado The Virgin River is still excavating. Upstream Plateau. This was not chaotic uplift, but from the Temple of Sinawava, in The Narrows, slow vertical hoisting of huge blocks of the the river cuts through Navajo Sandstone, crust. Zion’s elevation rose from near sea level creating a slot canyon. At the Temple of to as high as 10,000 feet above sea level. Sinawava, the river has reached the softer Uplift is still occurring. Kayenta Formation below. Water erodes the shale, undermining the overlaying sandstone For many millions of years, portions of the and causing it to collapse, widening the Pacific Plate (oceanic crust) subducted canyon. As the continue to rise, the beneath the thicker, more buoyant North basins drop, and the river cuts, Zion Canyon American Plate (continental crust). This is expanding upstream at a rate of about 10 subduction formed mountains and volcanoes miles of lateral movement every million years. along the west coast, and led to the formation of the Rocky Mountains. Later, changes in Volcanic Activity plate geometry led to the end of subduction Volcanic vents, created as a result of the along much of the West Coast (although weakening of the Earth’s crust during tectonic subduction continues today in the Pacific events, allowed flows and cinder cones to Northwest). Instead of being pushed together, form. Cinder was piled several hundred feet the plates began to slide sideways (lateral high in classic cone shapes and lava flowed motion), as is seen today in ’s into valleys. Cinder cones and black San Andreas Fault. This lateral motion flows are visible west of Rockville and on the stretched portions of North America; Kolob Terrace. creating a region called the Basin and Range. Westernmost Utah is part of the eastern Fractures and Faults edge of the Basin and Range province, where Fractures and their control of canyon erosion stretching continues today along active are one of the most striking features of the faults like the Hurricane and Wasatch Faults. canyons of the Virgin River. The fractures (not Despite the building and stretching faults because there is no displacement) exert that occurred in the surrounding areas, the a strong influence on the erosion of smaller rose to its high elevation canyons in the Navajo Sandstone. with little deformation. These fractures are believed to have formed Erosion due to tectonic compression and extension The uplift of the Colorado Plateau gave the forces. The fractures form perpendicular to streams greater cutting force in their descent the direction of the compression and to the sea. The park’s location on the extension. The dominant fracture direction western edge of this uplift caused the streams in Zion is roughly north-south. There are also to tumble off the plateau, flowing rapidly fracture sets that are east-west (Kolob down a steep gradient. These streams began Canyons) and northeast–southwest (Kolob eroding and cutting into the rock layers, Terrace and Hop ). forming deep and narrow canyons. While the straight north-south canyons Grain by grain, the Virgin River has carried on either side of Checkerboard are away several thousand feet of rock that once controlled by large fractures, the criss-cross lay above the highest layers visible today. On fractures on its surface are of a more average, the Virgin River transports one recent origin. The horizontal banding is the million tons of sediment per year. The rate result of differential weathering of the varies dramatically with the flow of the river, crossbedded sandstone, while the vertical with the vast majority of sediment transport cracks are thought to be the result of freeze/ occurring during floods. When the river is low thaw cycles at the surface of the rock. and clear, very little sediment is moving, and much of the transport involves minerals dissolved in the water.

Zion National Park, 2015 Landscapes: Past, Present, and Future 3 Landscapes: Past Background There are seven distinct rock layers in Zion Duration National Park which all were deposited 1 hour at different times and from different paleoenvironments. Location Indoors The Kaibab Formation (limestone) is the oldest exposed formation in the park where Key Vocabulary it occurs in small outcrops at the Kolob geologic processes, paleoenvironment, Kaibab Canyons area of the park. (It can also be seen Limestone, Moenkopi Formation, Chinle in the Hurricane Cliffs.) It was deposited Formation, Moenave Formation, Kayenta when a shallow tropical sea covered the area Formation, Navajo Sandstone, Temple Cap and it contains fossils of ancient marine Formation animals. The Moenkopi Formation was deposited in a coastal flood Objectives environment of streams and tidal flats, and By the end of the program, students will be consists of reddish brown siltstones and able to a) analyze images of some of Zion’s mudstones with gray gypsum-rich shale rock layers, b) view and discuss images of and limestone beds. Above the Moenkopi the Zion region as its various layers were Formation is the Chinle Formation, a mauve, deposited, and c) create posters showing what gray and white shale. During Chinle time, a the park looks like today and what it looked large river system flowed through the area, like when one of its layers was deposited. bringing large coniferous trees and volcanic ash which eventually led to formation of Method petrified wood. The overlying Moenave After analyzing the rock layers of Zion, Formation, consisting of reddish-brown students connect the geologic layers to siltstones and , was deposited by streams paleoenvironments. The activity concludes and . with creation of posters showing the students’ depictions of Zion during past geologic times compared to today.

Many of Zion’s different rock layers are visible in the main canyon including the Temple Cap Formation, Navajo Sandstone, Kayenta Formation, and the Moenave Formation. NPS

Zion National Park, 2015 Landscapes: Past, Present, and Future 4 Most of the spectacular scenery seen at Zion is due to the Jurassic Kayenta Formation and 4. Explain that the climate and landscape of Navajo Sandstone. The Kayenta Formation southwestern Utah was very different when was deposited in a river and each of the park’s rock layers was forming. environment and consists of a reddish-brown, Show the students the illustrations of interbedded sandstone, siltstone and shale. the paleoenvironments during different The Navajo Sandstone, which makes up the geologic times. Explain that the past large cliffs of Zion, was deposited when the environments shown on the illustrations entire Colorado Plateau region (and beyond) became the major layers of the canyon. turned into a vast sand desert. Shifting NPS/CAITLIN CECI winds blew sand into dunes, resulting in the 5. Referring to the geologic layers in the cross-bedding patterns seen in the rock today. photos and the description of each The Jurassic Temple Cap Formation, a tan to paleoenvironment, ask the students to gray sandstone, is exposed on higher plateaus imagine what the area looked like at those of Zion, most notably on top of The West times. Ask the students to think about the Temple. Younger Jurassic and Cretaceous types of animals and plants that might have formations are located at Zion’s highest lived in the area at that time, and compare elevations. and contrast their descriptions with the habitats in Zion today. Pleistocene volcanic rocks are exposed in the NPS/BRYANNA PLOG western part of the park. They were formed 6. Form groups of students and assign each from tectonic activity that produced cinder group one of the geologic layers shown on cones and basalt flows on mesa tops. the cross-section. Make sure each layer is assigned at least once in the classroom. Materials • Landscapes: Past images 7. Have students draw posters illustrating a) what the park looks like today and why Suggested Procedures it looks this way and then b) what the 1. Show the students the image of the Zion area looked like when the students’ geologic layers at Zion. Show the unlabeled assigned layer was being deposited,

NPS/SARAH STIO image of the geologic layers at Zion and including the plants and Close up on the Moenave see if the students can explain why there animals. After drawing both pictures on Formation. are different geologic layers and how they their poster, students should also write Petrified rock in the Chinle might have been deposited. Then show the captions describing them. Formation. image with the layers labeled and discuss Cross-bedding patterns in Navajo the observed differences in color, slope 8. Have students share their posters with Sandstone tell a story of shifting and, texture between layers. How many the class and describe the layers they winds and enormous sand dunes. different layers can they count? How many investigated. different colors do they see in the layers? Why do they think the layers look different from each other?

2. Ask the students to synthesize their ideas and describe how the fine particles of rock were deposited over millions of years. Students should recognize that the layers are different because different types of rocks and sand were deposited at different times as the environment changed.

3. Explain that each of the layers was deposited as part of many rock cycles over millions of years. Show the geologic cross- section and name each layer and the time period that it was formed.

Zion National Park, 2015 Landscapes: Past, Prsent and Future 5 Topographic map section of the lower canyon area of Zion National Park. Landscapes: Present closely spaced the lines, the steeper the slope. Conversely, gentle ground slopes are Duration portrayed by contours spaced widely apart. 1 hour can be identified on topographic maps. In this activity, mesas, cinder cones, and Location canyons will be identified. Indoors In dry climates like southern Utah, rocks can Key Vocabulary erode into mesas and buttes. The Mesa Map , contour line, erosion, shows two flat-topped plateaus bordered topographic map, uplift on all sides by steep cliffs. Mesas get smaller as their cliffs erode and become small, flat- Objectives topped called buttes. This map also After this activity, students will be able to: a) shows contour lines close to each other use a simple topographic map, b) name two representing a steep slope or . geological features on a map, and c) describe map features that were created through The Map shows contour lines spaced weathering and erosion. further apart that represent a gentle slope. On the Volcano Map the Earth’s hot mantle has Method pushed magma up in places and erupted lava Using a topographic map of the park, students to form a small volcano or cinder cone. The identify geological features present in Zion volcano map also shows drainages or canyons National Park today (e.g., canyons, mesas, with water (washes, ) that have a blue cinder cones) and describe changes that have line in-between branches of contour lines that occurred through geologic events. represent the surrounding canyon walls.

Background Topographic maps consist of contour lines that show elevation differences of the land surface. Each contour line connects points on the Earth’s surface that have the same elevation. Where contour lines are closely spaced, the terrain is steep. The more

Zion National Park, 2015 Landscapes: Past, Present, and Future 6 Materials • Landscapes: Present images • Identify trails (dashed black lines) • Zion Canyon topographic map • Find and name two high peaks (e.g., • Crayons or colored pencils Mt., Beehive Peak) • Mesa topographic features maps (student • Identify cliffs (very closely spaced and teacher version) contour lines on the majority of the map). • Volcano topographic features maps • Find gentle slopes (largely spaced (student and teacher version) contour lines, e.g., Sand Bench Trail, South Campground). Suggested Procedure 1. Use the student topographic features maps 5. Relate the build up and break down of (linked under materials above) to enable the Earth’s surface to the Zion area. Ask students to discover and visualize the students: features described above. On the mesa map, have the students find and label the • Where might uplift have occurred? mesas and an example of a steep slope. • Where is deposition occurring? • Where is weathering and erosion 2. On the volcano map, ask the students to occurring? find and label the small volcano called • What would likely happen if the area were Crater and the 4,600-foot contour to be uplifted even more? line that surrounds the crater. Ask the students to color between each of the 6. Have students write a paragraph describing heavier contour intervals (spaced every five how the area would look if there contours) with a different color between were no mountain uplift, weathering, or each heavier line. Discuss spacing between erosion. Ask a few students to share their contours and how spacing shows steep or paragraphs and justify their answers. gentle slopes.

3. Have students relate the building up and breaking down of the Earth’s surface to the landforms they identified. Following are examples of questions you might ask:

Mesa Map: • What might cause a mesa to form? [uplift and erosion] • Why is the slope gentler at the base of mesas? [deposition; erosion and weathering break the rocks down and the material is deposited at the base, different rock types.]

Volcano Map: • What does a river create? [canyon] • How long did it take for the different geologic events to create the various landscapes that you see on the volcano map?

4. Continue by using the canyon topographic map (linked under Materials above). On this topographic map, have students:

Zion National Park, 2015 Landscapes: Past, Prsent and Future 7 Landscapes: Future • Where is the approximate location of southwestern Utah on the map? Duration • Does it look like the area is underwater or 1 hour very near an ocean inlet? • What kind of fossils will we find in the 100 Location million year layer? Classroom with a cleared space or outdoors • After the landscape changes in another 200 million years, what do you imagine it will Key Vocabulary look like?

NPS/BRYANNA PLOG tectonic plates, paleoenvironment 2. Have the students draw maps and pictures Objectives of the landscape of southwestern Utah After completing this activity, students will be based on the landscape predicted in the able to a) predict future landscapes at Zion video animation. Have the students use based on the understanding of geologic their imagination and add plants and processes, b) use performance skills to animals to the future landscape. describe the proposed landscape at Zion 3. Once the students have completed their National Park 100 million years in the future, pictures, have them share the drawings with and c) draw posters of Zion’s proposed the class. landscape 100 million years in the future. NPS/BRYANNA PLOG Evaluation Method Ask students to talk about the experience of Watch the video of the tectonic changes in thinking about the future landscape of the past and predicted changes in 100 million southwestern Utah in 100 million years. years. Tell students that they are going to draw on the knowledge that they already have • How will people adapt over millions about the geologic events to draw pictures and of years as the landscape changes describe the landscape of southwestern Utah and southwestern Utah is eventually 100 million years in the future. underwater? • Do you think people will still be here? NPS/BRYANNA PLOG Background • Are there both fast and slow changes What will Zion National Park This post-visit activity is designed help that occur in the landscape? Name three look like in 100 million years? Only time will tell. students reflect on what they have learned, fast geologic processes and three slow assess their knowledge, and predict future processes of landscape change. changes to the landscape of southwestern • If such drastic landscape changes happen Utah in 100 million years. naturally over millions of years, why is it still necessary for us to take care of the Materials present landscapes and environment? • Drawing paper and color markers, pencils and pens • Classroom computers • Download or view YouTube video showing historical evolution of tectonic plates through 100 million years in the future http://www.youtube.com/watch?v=uGcDe d4xVD4&NR=1&feature=fvwp

Suggested Procedure 1. Watch the video. Then watch it again and pause it on the final scenes showing the position of the North American tectonic plate where Utah is located 100 million years in the future. Ask the students:

Zion National Park, 2015 Landscapes: Past, Present, and Future 8 Glossary

earthquake: the result of a sudden release of Basin and Range: type of topography that is energy in the Earth’s crust that creates seismic characterized by a series of tilted fault blocks waves. forming or mountains and broad, intervening basins or valleys. erosion: the movement of weathered materials by natural processes. blind arch: a curved structure created by natural geological forces causing rock to fall extrusive rock: rock produced by molten lava away, with a rock face behind so there is no that flows onto the surface of the Earth (also window through the arch. called volcanic rock). : a steep-sided hill with a flat top, often fault: the boundary between two rock standing alone in an otherwise flat area. A sections that have been displaced relative to butte is smaller than a mesa. each other. cementation: the process in which the spaces fold: a bend in a layer of rock. between loose particles are filled with a hardening or bonding agent. This is one form fossil: the mineralized or otherwise preserved of lithification. remains or traces (such as footprints) of animals, plants, and other organisms. Chinle Formation: a rock layer consisting of a conglomerate and brightly colored geology: the science and study of the solid shales, , volcanic ashes, and earth and the processes by which it is shaped thin of various compositions. and changed. Characteristic features are picturesque erosion forms and petrified wood. geologic processes: a scientific term used to describe the internal and external forces that cinder cone: a steep, conical hill of volcanic shape the physical makeup of the Earth. fragments that accumulates around and downwind from a volcanic vent. geologic time scale: used by and other scientists to describe the timing and Colorado Plateau: a large uplifted plateau relationships between events that have roughly centered on the four corners region occurred during the history of Earth. (Utah, , Colorado, and ) of the southwestern United States. : geologic study of the configuration and evolution of land forms. compaction: the process by which overlying rock layers or sediments compress the spaces : rock produced by the cooling between underlying particles. This is one form and solidification of magma, either on or of lithification. below the Earth’s surface. contour line: an imaginary line that joins intrusion: the pushing up of magma into points of equal elevation on the surface of the pre-existing rocks. land above or below a reference surface, such as mean sea level. Contours make it possible intrusive rock: rock produced by the cooling to measure the height of mountains, depths of of magma deep beneath the Earth’s surface the ocean bottom, and steepness of slopes. (also called plutonic rock). crater: a pit or hole in the ground created by Kaibab Formation: a rock layer consisting of an explosion such as a volcanic eruption, or limestone and containing marine fossils. from the impact of a meteorite.

deposition: the geological process by which material is added to a landform or land mass.

Zion National Park, 2015 Landscapes: Past, Present, and Future 9 Kayenta Formation: a rock layer that was plate tectonics: theory of geology that has deposited in a river and flood-plain been developed to explain the observed environment and consists of a reddish-brown, evidence for large scale motions of the Earth’s interbedded sandstone, siltstone and shale. lithosphere.

landslide: the downslope movement, under plateau: also called a high plain or tableland, gravity, of masses of soil and rock material is an area of high elevation land, usually such as rockfall, slump, and debris slide. consisting of relatively flat terrain.

lava: magma that emerges onto the surface of relative age: the age of a rock in comparison the Earth. to other rocks.

lithification: the processes in which rock cycle: interrelated sequence of events sediments become solid rock. by which rocks are initially formed, altered, destroyed, and reformed as a result of lithospheric plates: a massive, irregularly magmatism, erosion, sedimentation (or shaped slab of solid rock, generally composed deposition), lithification, and metamorphism. of both continental and oceanic lithosphere (also called tectonic plates); part of plate scientist: in a broad sense is one engaging in a tectonics. systematic activity to acquire knowledge. In a more restricted sense, a scientist is an magma: molten rock deep within the Earth. individual who uses the scientific method.

mesa: (Spanish and Portuguese for “”) an : rock produced from elevated area of land with a flat top and sides particles deposited by wind, water, ice, or that are usually steep cliffs. It takes its name chemical reactions. from its characteristic table-top shape and is larger than a butte. sediment: finely divided solid material, ex: sand, gravel, mud. metamorphic rock: rock that has undergone change as a result of intense heat and pressure. subduction: a geologic process in which one edge of a crustal plate descends below Moenave Formation: a rock layer consisting another. of reddish-brown siltstones and shales, deposited by streams and lakes. topographic map: a representation of the Earth, or part of it, showing the shape of the Moenkopi Formation: a rock layer deposited Earth’s surface with contour lines. in a coastal flood plain environment of streams and tidal flats, consisting of reddish uplift: a geological process most often caused brown siltstones and mudstones with gray by plate tectonics which increases elevation. gypsum rich shale and limestone beds. volcano: an opening, or rupture, in a planet’s Navajo Sandstone: the rock layer which surface or crust, which allows hot, molten makes up the large cliffs of Zion; it was rock, ash and gases to escape from below the deposited when the entire Colorado Plateau surface. region (and beyond) turned into a vast sand dune desert. Shifting winds blew sand into weathering: decomposition of rocks, soils, dunes, resulting in the cross-bedding patterns and their minerals by chemical or physical seen in the rock today. processes. Chemical weathering involves a chemical change in at least some of the paleoenvironment: the past environment of minerals within a rock. Mechanical an area during a given period of its history. weathering involves physically breaking rocks into fragments without changing the chemical make-up of the minerals within it.

Zion National Park, 2015 Landscapes: Past, Present, and Future 10 References

Colorado Plateau Geosystems, Inc. Reconstructing the Ancient Earth, http:// cpgeosystems.com/gallery.html. Last modified 2010.

Federal Emergency Management Agency. Seismic Sleuths: A teacher’s package for grades 7-12, 2nd Edition. D.C.: American Geophysical Union, 1995

Hislop, Teresa, and Kirstin Reed. Topographic maps, http://www.uen.org/Lessonplan/ preview?LPid=2209. Last modified 2002.

National Geographic. How was the Grand Canyon formed? http://www. nationalgeographic.com/expeditions/ lessons/07/g35/canyon35.html. Last modified 2011.

U.S. Geological Survey. What’s the difference between weathering and erosion? http:// geomaps.wr.usgs.gov/parks/misc/gweaero. html. Last modified 2014.

Zion National Park, 2015 Landscapes: Past, Present, and Future 11