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Explore the research of Dr. Celina Suarez and her team of scientists, who uncovered evidence of the End Triassic Extinction in the rock layers of Zion National Park! Step into the past to an age before the dinosaurs to learn about what this environment was like, how the climate changed over millions of years, and how we know.
Paleo artist Brian Engh worked with Dr. Suarez and Zion National Park staff to create this exhibit, which is currently on display at the Human History Museum.
Audio described versions of each panel are available on this page.
Art by Thuat Tran and Brian Engh
Reading the Rocks
The towering sandstone cliffs and sweeping plateaus of Zion National Park hold stories of the past. These stories help us understand the plants, animals, and ecosystems of the past, which can help us understand the present and plan for the future.
Geologists are scientists who study the Earth's rocks. Geologists can look at a variety of things in the rocks to tell us about the past. Some of the things they look at are patterns and structures in the rock, the rock's chemistry and mineral content, and the fossil remains of living things preserved in the layers.
Geologists refer to sets of similar rocks that can be mapped on the landscape as “geologic formations”. It is important to map out where fossils are deposited, and study the rock layers they are buried in to determine what environments they were deposited in. Fossils may be preserved anywhere that sediments such as clay, sand, or volcanic ash might settle and bury evidence of ancient living things.
Dr. Celina Suarez is a geologist who is researching rocks in Blacks Canyon in Zion National Park. She and her team of researchers chose this area because of a significant story hidden in these layers: the End Triassic Extinction. The Triassic Period was the first in the age of dinosaurs. These early dinosaurs were small and not very abundant.
The End Triassic Extinction
Study of the fossil record has revealed that around 201 million years ago, 75% of all life on Earth went extinct, from large animals to small aquatic corals. This is known as the End Triassic Extinction, and it cleared the way for dinosaurs to diversify into a wide variety of habitats left vacant by so many other animals going extinct.
Dr. Suarez and her team have identified evidence of this important extinction event by looking at chemical markers preserved in the rocks in Zion National Park.
By studying this event, we can learn more about what happened, what caused it, and what lessons we can learn from it. Improving our understanding of past events can help us make better informed decisions today.
ETE - Reading The Rocks audio description
Audio description of panel 1 of the End Triassic Extinction exhibit.
Text: Reading the Rocks. The towering sandstone cliffs and sweeping plateaus of Zion National Park hold stories of the past. These stories help us understand the plants, animals, and ecosystems of the past, which can help us understand the present and plant for the future.
Description: Underneath the title and caption is a photo of orange and red sandstone cliffs. Beneath the cliffs, there are rolling foothills dotted with green vegetation. To the right of this photo is a colorful stratigraphy (struh-tig-ruh-fee) column, which shows the rock layers of Zion and the fossils that have been found in each layer.
Starting at the bottom of the column, there is a light purple section labeled, “Chinle” (chin-lay), which includes, “Shinarump (shin-uh-rump) Conglomerate”. There are six drawings next to this layer, including a fish;
Description: A four-legged animal with a tail the same length as its body and a rounded face with a large, open jaw;
Text: Ruvueltosaurus aff. R. callenderi. Heckert et al, 2006. (pronounced: roo-velt-oh-sore-us)
Description: An alligator-like animal with a flat body, long tail, and a long mouth of sharp teeth.
Text: Phytosauria indet. DeBlieux et al 2006. (pronounced: fight-oh-sore-ee-uh)
Description: Above the purple Chinle rock layer is a thin red layer labeled “Moenave,” (mo-uh-nah-vay) which includes “Dinosaur Canyon.” A red line crosses through the rock layer to indicate the “Extinction Event.”
Above the Moenave layer is a light blue section labeled, “Whitmore Point”. To the right of this layer are five light blue drawings, including two fish;
Text: New coelacanth 2023 (pronounced: see-low-canth)
Description: A plant with leaves arranged in a “V” shape from a central point;
Description: Two animal footprints, the first with three toes at the front of the foot and one toe towards the rear. The second print has three pointed toes and a rounded heel.
Text: Eubrontes or Anomoepus. DeBlieux et al 2006. (pronounced: you-brawn-tees or ann-oh-mow-pus)
Description: The next rock layer is labeled, “Kayenta” (kai-en-tuh), which includes “Springdale Sandstone, Main body, Lamb Point, and Tenney (ten-ay?) Canyon”. This layer is colored orange and includes four drawings, showing a fish
Description: Four thin footprints with three toes. The middle toe is longer than the toes on either side.
Text: Grallator (pronounced: gr-ow-later)
Description: At the very top, the thickest rock layer is colored light yellow, labeled “Navajo Sandstone”. There are four yellow drawings to its right, beginning with a sketch of a variety of footprints,
Text: Diverse track block. DeBlieux et al. 2006
Description: A furry, four-legged animal with long whiskers and a pointed tail.
Text: Possible trackmaker. Kayentatherium. (pronounced: k-eye-ent-uh-there-ee-um)
Description: A large dinosaur standing on two legs with a long tail, furry back, and two ridges on its face.
Text: Possible Eubrontes trackmaker. Dilophosaurus. (pronounced: you-brawn-tees and die-lof-o-sore-us)
Description: a smaller, furry dinosaur with a long face and neck.
Text: possible grallator trackmaker. Coelophysis. (pronounced: growl-later and see-lo-f-eye-sis)
Description: The lower left corner of the exhibit panel has two photos. The top is of a woman sitting on a red, rocky slope writing notes in a notebook. The bottom photo shows the same woman now sitting indoors looking through a microscope.
Text: Geologists are scientists who study the Earth’s rocks. Geologists can look at a variety of things in the rocks to tell us about the past. Some of the things they look at are patterns and structures in the rock, the rock’s chemistry and mineral content, and the fossil remains of living things preserved in the layers.
Geologists refer to sets of similar rocks that can be mapped on the landscape as “geologic formations”. It is important to map out where fossils are deposited, and study the rock layers they are buried in to determine what environments they were deposited in. Fossils may be preserved anywhere that sediments such as clay, sand, or volcanic ash might settle and bury evidence of ancient living things.
Dr. Celina Suarez is a geologist who is researching rocks in Blacks Canyon in Zion National Park. She and her team of researchers chose this area because of a significant story hidden in these layers: the End Triassic Extinction. The Triassic Period was the first in the age of dinosaurs. These early dinosaurs were small and not very abundant.
Description: A photo of two smiling geologists in sunglasses and hats. The geologists point to a red rock on a steep slope.
Text: The End Triassic Extinction. Study of the fossil record has revealed that around201 million years ago, 75% of all life on Earth went extinct, from large animals to small aquatic corals. This is known as the End Triassic Extinction, and it cleared the way for dinosaurs to diversify into a wide variety of habitats left vacant by so many other animals going extinct.
Dr. Suarez and her team have identified evidence of this important extinction event by looking at chemical markers preserved in the rocks in Zion National Park.
By studying this event, we can learn more about what happened, what caused it, and what lessons we can learn from it. Improving our understanding of past events can help us make better informed decisions today.
Description: The panel ends with three red dinosaur tracks.
Brian Engh
~227-205 Million Years Ago: Thriving Tropical Wetlands
Mudstones and sandstones are our first clues about the environment that deposited the Chinle Formation. Logs from tall conifer trees, leaves from moisture-loving ferns, and a wide variety of other plant life are commonly found fossilized in these layers of sand and mud. Fossils of fish, giant amphibians, and large prehistoric reptiles including semi-aquatic phytosaurs also give us hints about the Late Triassic environment.
The Late Triassic environment was shaped by meandering rivers and seasonal floods that formed wetlands and ponds teeming with life in a warm, wet, and tropical climate.
A Drifting Continent
Over 22 million years, the continent slowly drifter further north into a warmer, more arid climate. Geochemical evidence indicates that the climate was changing while the Chinle Formation was being deposited, but it was changing slowly, which allowed animals and plants time to adapt.
Where are all the dinosaurs?
While the Chinle Formation preserves many prehistoric reptiles, only a few were dinosaurs. As other groups of Triassic reptiles went extinct, small dinosaurs, like these Coelophysis survived.
Paleontologists Don DiBlieux and Andrew Milner excavating the phytosaur skull featured in this exhibit from the Chinle Formation.
Can you find the phytosaur lurking in the illustration?
Text: approximately 227 to 205 million years ago. Thriving tropical wetlands.
Description: Below the panel’s title is a large illustration of a prehistoric environment, full of plants and animals in and around a body of water. The body of water has a variety of colorful fish and a large, alligator-like animal with its long mouth lined by sharp teeth. Above, on the muddy shores, are a variety of other prehistoric animals eating, drinking, fighting, and resting. Further offshore are tall trees, ferns, and segmented plants with thin leaves. A winged animal flies overhead against a cloudy, dark sky.
Text: Mudstones and sandstones are our first clues about the environment that deposited the Chinle Formation. Logs from tall conifer trees, leaves from moisture-loving ferns, and a wide variety of other plant life are commonly found fossilized in these layers of sand and mud. Fossils of fish, giant amphibians, and large prehistoric reptiles including semi-aquatic phytosaurs also give us hints about the Late Triassic environment.
The Late Triassic environment was shaped by meandering rivers and seasonal floods that formed wetlands and ponds teeming with life in a warm, wet, and tropical climate.
Description: To the right of this text is a globe showing the supercontinent Pangea, with a yellow arrow pointing to where Zion National Park would be at this time in the Late Triassic.
Text: A drifting continent. Over 22 million years, the continent slowly drifter further north into a warmer, more arid climate. Geochemical evidence indicates that the climate was changing while the Chinle Formation was being deposited, but it was changing slowly, which allowed animals and plants time to adapt.
Description: A chart on a purple background labeled “Chinle Paleoclimatic Trend” shows three different lines spanning from 224 million years ago to 208 years ago. The blue line for “precipitation” begins high on the chart but ends much lower. This shows the change from 200 centimeters to 40 centimeters of average annual precipitation. A gray line with dark arrows shows an increase from 420 parts per million to 2000 parts per million atmospheric carbon dioxide. A red line with white stripes shows a gradual change from 20 degrees Celsius to 24 degrees Celsius average annual temperature. A note at the bottom reads, “Modern atmospheric carbon dioxide = 427 parts per million”.
Text: Note that this graph spans 16 million years.
Description: Beneath the chart is a pack of six long-tailed dinosaurs, all of which are walking on two legs.
Text: Where are all the dinosaurs? While the Chinle Formation preserves many prehistoric reptiles, only a few were dinosaurs. As other groups of Triassic reptiles went extinct, small dinosaurs, like these Coelophysis survived. (pronounced: see-lo-fie-sis)
Description: Two photos on the left show a pair of scientists in a rocky field sitting next to a large white cast. The cast is wrapped around a long skull.
Text: Paleontologists Don DiBlieux and Andrew Milner excavating the phytosaur skull featured in this exhibit from the Chinle Formation.
Description: A white magnifying glass labeled “Junior Paleontologist” sits just beneath the photo of the wrapped phytosaur skull.
Text: Can you find the phytosaur lurking in the illustration above?
Brian Engh
~204-201 Million Years Ago: A Drying Landscape
Drying floodplains and shrinking rivers. The layers of mud and sandstone that form the Moenave Formation span approximately 4 million years of time. Evidence found in these layers tell us that there were major changes in the landscape and climate. Dinosaurs may have lived with these changes better than other groups of Triassic animals.
Heading North
Continental drift moved North America from the wet tropics into a dry belt.
As North America continued to drift further north into temperate climates, it became cooler, drier, and more seasonal. What were once big rivers and expansive floodplains shrank to seasonal streams and lakes; old growth forests became fragmented woodlands, arid scrublands, and desert sand dunes. Changing environments meant changes in animal and plant life, with some species dwindling as a result.
As the climate dried, some Triassic animals went extinct, but these environmental changes were about to become much more dramatic. Small dinosaur footprints are among rare fossils found in the Dinosaur Canyon Member of the Moenave Formation, indicating that small dinosaurs managed to survive in these harsher environments. As other Triassic animals struggled, many habitats and ecological roles were left vacant, allowing space for new dinosaurs to eventually evolve into them.
Dr. Celina Suarez and her team survey for rocks to sample in the Dinosaur Canyon Member of the Moenave Formation. Very few fossils have ever been found in the Dinosaur Canyon Member, but the chemistry of its rocks help us to understand the ancient climate.
ETE - A Drying Landscape audio description
Audio description of Panel 3 of the End Triassic Extinction exhibit
Text: Approximately 204 to 201 million years ago, a drying landscape.
Description: Beneath the title, a bright illustration of a prehistoric environment spans the exhibit panel. It shows a shallow pool of water dotted with thin, segmented reeds and leafy, green aquatic plants, which have red flowers on a spike. In the pool, a large reptile is taking down a smaller, furry animal while a frog leaps away. The muddy shores of the pool show the footprints of a dinosaur and the ripple pattern of the water. A tree leans over the pool, standing out against a bright blue sky with sparse clouds. Various prehistoric plants and animals are scattered around the scene, including a small herd of long-necked animals, several four-legged creatures with long striped tails, and a small, iguana-like reptile emerging from under hand-shaped leaves.
Text: Drying floodplains and shrinking rivers. The layers of mud and sandstone that form the Moenave Formation span approximately 4 million years of time. Evidence found in these layers tell us that there were major changes in the landscape and climate. Dinosaurs may have lived with these changes better than other groups of Triassic animals.
Description: To the right of this text is a globe showing the supercontinent Pangea with a yellow arrow pointing to where Zion National Park would be at this time in the Late Triassic. Next to the globe is a large green arrow pointing upwards, matching the direction of North America’s continental drift.
Text: Heading north. Continental drift moved North America from the wet tropics into a dry belt.
As North America continued to drift further north into temperate climates, it became cooler, drier, and more seasonal. What were once big rivers and expansive floodplains shrank to seasonal streams and lakes; old growth forests became fragmented woodlands, arid scrublands, and desert sand dunes. Changing environments meant changes in animal and plant life, with some species dwindling as a result.
Description: A chart on a purple background labeled “Lower Dinosaur Canyon Paleoclimatic Trend” shows three different lines spanning from 203.8 million years ago to 201.8 years ago. A light blue line for precipitation shows a slight decrease, from 50 centimeters to 40 centimeters of average annual precipitation. A grey line filled with dark arrows shows no change from 2000 parts per million atmospheric carbon dioxide. A red line with white stripes shows a slight increase from 24 degrees Celsius to 27 degrees Celsius average annual temperature. A note at the bottom indicates that modern atmospheric carbon dioxide is 427 parts per million.
Text: Note that this graph spans 2 million years.
As the climate dried, some Triassic animals went extinct, but these environmental changes were about to become much more dramatic. Small dinosaur footprints are among rare fossils found in the Dinosaur Canyon Member of the Moenave Formation, indicating that small dinosaurs managed to survive in these harsher environments. As other Triassic animals struggled, many habitats and ecological roles were left vacant, allowing space for new dinosaurs to eventually evolve into them
Description: A photo of three people hiking up a steep cliff. The cliff is composed of red dirt and dotted with sparse shrubs.
Text: Dr. Celina Suarez and her team survey for rocks to sample in the Dinosaur Canyon Member of the Moenave Formation. Very few fossils have ever been found in the Dinosaur Canyon Member, but the chemistry of its rocks help us to understand the ancient climate.
Description: The bottom left corner of the exhibit shows an illustration of a long phytosaur skull sitting half-buried in dry, cracking red dirt. On the dirt are skeletons of dead fish along with fresh footprints from a dinosaur, whose distant silhouette is blurred by a mirage. In the background, a forest fire is visible.
Brian Engh
201.6-200.6 Million Years Ago: A World Torn Apart
Within the Moenave Formation are a series of mudstones and siltstones that tell the short but catastrophic story of the End Triassic Extinction. These unassuming layers of rock record in their chemical composition major changes in the atmosphere. The change in chemical composition was recorded by Triassic plants, because plant life absorbs carbon dioxide (CO2) from the atmosphere and deposits as carbon in the soil. The chemical changes recorded during this short time period indicate a quick and sharp increase in CO2 in the Triassic atmosphere. These rapid changes in climate and the environment led to the extinction of around 75% of species on Earth during this short period of time.
Splitting the Triassic Supercontinent
Near what is now the east coast of North America, hot magma churning deep within the Earth was surging up towards the surface. As it moved upward, it pushed through the rocks forming the Earth’s crust, which caused the continents to break apart. As magma steadily surged upward, it bubbled up through layers of rock rich in oil, natural gas, and coal, which released large amounts of CO2 and methane.
A Lethal Chain Reaction
Gasses rapidly released by volcanic activity insulated the global atmosphere and trapped the sun’s energy, like a greenhouse heating up under the sun’s rays. When the atmosphere traps more heat, the oceans heat up and more water evaporates into the air. This means more warm water to fuel massive rainstorms which increased plant growth – fuel for wildfires. Scientists detected biomarkers for smoke from extreme wildfire events in these periods of great climate instability following spikes in greenhouse gases.
Extensive mud cracks preserved in the Upper Dinosaur Canyon Member and geochemical markers point to hot, dry conditions and frequent wildfires followed by wet, rainy cycles.
Image captions
Somewhere in the Pangean rift zone, a family of early sauropodomorph dinosaurs flees a rift valley as a rift eruption floods the region with basalt lava, while the upwelling magma heats layers of fossil-rich Carboniferous rocks, releasing the carbon trapped within them into the atmosphere.
Geologist Asher Boudreaux breaks off a piece of siltstone to test its geochemical makeup in the upper part of the Dinosaur Canyon Member of the Moenave Formation.
Dr. Celina Suarez samples mudstones in the Dinosaur Canyon Member of the Moenave Formation. These samples will be crushed and analyzed in Suarez’s laboratory.
ETE - A World Torn Apart audio description
Audio description of Panel 4 of the End Triassic Extinction exhibit
Text: 201.6 to 200.6 million years ago. A world torn apart.
Description: A photo of a red sandstone rock with a black and white measuring device next to it.
Text: Within the Moenave Formation are a series of mudstones and siltstones that tell the short but catastrophic story of the End Triassic Extinction. These unassuming layers of rock record in their chemical composition major changes in the atmosphere. The change in chemical composition was recorded by Triassic plants, because plant life absorbs carbon dioxide (CO2) from the atmosphere and deposits as carbon in the soil. The chemical changes recorded during this short time period indicate a quick and sharp increase in CO2 in the Triassic atmosphere. These rapid changes in climate and the environment led to the extinction of around 75% of species on Earth during this short period of time.
Description: A globe showing the supercontinent Pangea with a yellow arrow pointing to where Zion National Park would be at this time in the Late Triassic. A large red area labeled “Rift Zone” is overlaid between the land that would become North America, Africa, and South America.
Text: Splitting the Triassic supercontinent. Near what is now the east coast of North America, hot magma churning deep within the Earth was surging up towards the surface. As it moved upward, it pushed through the rocks forming the Earth’s crust, which caused the continents to break apart. As magma steadily surged upward, it bubbled up through layers of rock rich in oil, natural gas, and coal, which released large amounts of CO2 and methane.
Description: Beneath this text is a chart on a black background titled, “Upper Dinosaur Canyon Paleoclimatic Trend”, with three lines spanning from 201.6 to 200.4 million years ago. The light blue line for precipitation stays fairly flat until a spike near the end. It shows a change from 50 centimeters, up to 90 centimeters, back down to 60 centimeters of average annual precipitation. The grey line (filled with dark arrows) shows a pattern of sharp increases and decreases in atmospheric carbon dioxide, from 2000 parts per million at the lowest point to 4000 parts per million at the highest. Each of the four peaks has a fire symbol indicating extreme wildfire events. The red line (with white stripes) indicates temperature, showing a pattern that mimics the increases and decreases of carbon. This line illustrates the large fluctuations in average annual temperature.
Text: A lethal chain reaction. Gasses rapidly released by volcanic activity insulated the global atmosphere and trapped the sun’s energy, like a greenhouse heating up under the sun’s rays. When the atmosphere traps more heat, the oceans heat up and more water evaporates into the air. This means more warm water to fuel massive rainstorms which increased plant growth – fuel for wildfires. Scientists detected biomarkers for smoke from extreme wildfire events in these periods of great climate instability following spikes in greenhouse gases.
Description: A white magnifying glass labeled, “Junior Paleontologist” points out that, “This is where the term ‘greenhouse gas’ comes from.”
Text: Extensive mud cracks preserved in the Upper Dinosaur Canyon Member and geochemical markers point to hot, dry conditions and frequent wildfires followed by wet, rainy cycles.
Description: The top right corner of the exhibit is taken up by an illustration of a huge dinosaur with a long neck leading three smaller dinosaurs through a dark, rocky rift valley. In the background, an erupting volcano shoots out bright orange lava, which is now flowing towards the dinosaurs.
Text: Above: Somewhere in the Pangean rift zone, a family of early sauropopmorph dinosaurs flees a rift valley as a rift eruption floods the region with basalt lava, while the upwelling magma heats layers of fossil-rich Carboniferous rocks, releasing the carbon trapped within them into the atmosphere.
Description: A series of three photos shows geologists on steep slopes excavating sections of rock. These geologists use tools like picks to break apart the stone.
Text: Geologist Asher Boudreaux breaks off a piece of siltstone to test its geochemical makeup in the upper part of the Dinosaur Canyon Member of the Moenave Formation.
Dr. Celina Suarez samples mudstones in the Dinosaur Canyon Member of the Moenave Formation. These samples will be crushed and analyzed in Suarez’s laboratory.
Brian Engh
~200-195 Million Years Ago: Ecosystems Reshaped
New life in an unstable climate.
The rock layers of the Whitmore Point Member of the Moenave Formation show us that the Early Jurassic climate initially became seasonally wet. This is because the hot atmosphere from the End Triassic Extinction held more water and caused intense rainstorms. This increased precipitation formed rivers and lakes. Wet seasons were followed by drying and increased wildfires. The fossils found in the Whitmore Point show us that these lakes and rivers supported diverse plant life, fish, and North America’s first large dinosaurs evolving into the ecological spaces left open after the End Triassic Extinction.
ETE - Ecosystems Reshaped audio description
Audio description for Panel 5 of the End Triassic Extinction exhibit
Text: approximately 200 to 195 million years ago, ecosystems reshaped.
Description: A large illustration of fish, amphibians, and reptiles underwater. A variety of fish hunt or hide around a sunken, algae-covered tree. The lower half of a dinosaur is seen swimming through the water, with its toes leaving deep marks in the soft soil.
Text: New life in an unstable climate. The rock layers of the Whitmore Point Member of the Moenave Formation show us that the Early Jurassic climate initially became seasonally wet. This is because the hot atmosphere from the End Triassic Extinction held more water and caused intense rainstorms. This increased precipitation formed rivers and lakes. Wet seasons were followed by drying and increased wildfires. The fossils found in the Whitmore Point show us that these lakes and rivers supported diverse plant life, fish, and North America’s first large dinosaurs evolving into the ecological spaces left open after the End Triassic Extinction.
Brian Engh
~195-185 Million Years Ago: Jurassic Deserts Develop
New creatures adapted to a seasonal environment.
In the Kayenta Formation, the rock layers show more seasonal dryness, but large and small dinosaurs continued to be abundant. The latest evidence suggests that dinosaurs, pterosaurs, and mammals were able to survive the harsh and unstable climate of the End Triassic Extinction and the Early Jurassic because they were all well-adapted for regulating their body temperature.
Pterosaurs and dinosaurs are distant relatives, and recent fossil discoveries from later in the Jurassic Period have shown that several groups of dinosaurs and pterosaurs were covered in very similar feathers. Because they both evolved from a shared common ancestor, paleontologists now think that feathers most likely evolved sometime in the Triassic Period.
ETE - Jurassic Deserts Develop audio description
Audio Description of Panel 6 of the End Triassic Extinction exhibit
Text: Approximately 195 to 185 million years ago, Jurassic deserts develop.
Description: A large, colorful illustration of a dinosaur overlooking a floodplain lined with vegetation and tall sand dunes. The dinosaur has a large, beak-shaped orange mouth and snout, bright brown eyes, and a long neck. Insects fly around its head.
Text: New creatures adapted to a seasonal environment.In the Kayenta Formation, the rock layers show more seasonal dryness, but large and small dinosaurs continued to be abundant. The latest evidence suggests that dinosaurs, pterosaurs, and mammals were able to survive the harsh and unstable climate of the End Triassic Extinction and the Early Jurassic because they were all well-adapted for regulating their body temperature.
Pterosaurs and dinosaurs are distant relatives, and recent fossil discoveries from later in the Jurassic Period have shown that several groups of dinosaurs and pterosaurs were covered in very similar feathers. Because they both evolved from a shared common ancestor, paleontologists now think that feathers most likely evolved sometime in the Triassic Period.
Brian Engh
~185-180 Million Years Ago: Life in a Sea of Sand
Surviving in a harsh desert landscape.
High up in the cliffs of Zion National Park, the river and floodplain deposits of the Kayenta Formation are overlaid by Navajo Sandstone, which makes up many of the most dramatic cliffs inn Zion Canyon. Navajo Sandstone preserves very few fossilized plants or bones, indicating that water was scarce in the vast, dune-covered landscape. Fossil footprints from dinosaurs and early mammals show us that they survived in small oases of the vast sandy deserts that were here when this layer was deposited.
ETE - Life in a Sea of Sand audio description
Audio description of Panel 7 of the End Triassic Extinction exhibit
Text: Approximately 185 to 180 million years ago. Life in a sea of sand.
Description: A colorful illustration fills the top two-thirds of the panel. This scene takes place among huge, sweeping sand dunes under a blue sky. A small oasis with the silhouette of plants is just visible in the distance. In the foreground stands a long-necked, tan dinosaur with yellow-green spots ringed in dark brown. A crest of thin red filaments stands up from the crown of its head. Behind this animal are two palm tree-like plants with fronds of long green leaves growing from its branches. Two smaller dinosaurs stand among the trees, both of which also have long, spotted necks. One dinosaur extends its tongue up towards a leaf.
Text: Surviving in a harsh desert landscape. High up in the cliffs of Zion National Park, the river and floodplain deposits of the Kayenta Formation are overlaid by Navajo Sandstone, which makes up many of the most dramatic cliffs inn Zion Canyon. Navajo Sandstone preserves very few fossilized plants or bones, indicating that water was scarce in the vast, dune-covered landscape. Fossil footprints from dinosaurs and early mammals show us that they survived in small oases of the vast sandy deserts that were here when this layer was deposited.
Brian Engh
Pieces of a Puzzle
Around the world, geologists study rocks to understand the past. By studying the fossilized remains of past life, the chemical composition of rocks, and their internal structures, scientists are able to describe past environments and significant events that happened long ago.
Paleontologists, who study fossils, record the types of life forms found in each rock layer, and their abundance. These lines of evidence help us understand how ecosystems were affected in response to changes in the atmosphere and climate.
In Blacks Canyon of Zion National Park, Dr. Celina Suarez and her team discovered the chemical signatures of the End Triassic Extinction. This major discovery supports evidence found by scientists around the world that the Triassic Extinction was driven by rapid release of the greenhouse gas carbon dioxide (CO2) into the atmosphere.
Scientists of all kinds work together to improve our knowledge of global ecosystems using the most up-to-date techniques to gather evidence and check each other’s work. Together, we can use evidence to better understand how our world works, and how ecosystems respond to sudden changes in Earth’s atmosphere.
Our world is a complex puzzle and researchers are vital to finding and connecting pieces that reveal the bigger picture. By working together, we can all contribute to a better understanding of nature.
Description: A large photo of a scientist standing on a steep, rocky, grey slope takes up the upper left corner of the exhibit panel. She is bent over, looking through a measuring device mounted to a black pole in the ground.
Text: Pieces of a puzzle. Around the world, geologists study rocks to understand the past. By studying the fossilized remains of past life, the chemical composition of rocks, and their internal structures, scientists are able to describe past environments and significant events that happened long ago.
Description: Below the text are two photos of scientists hiking in red, sandy hills dotted with green shrubs. The photo on the left shows a researcher with a backpack on his back crouched on the ground to measure a flat rock while another researcher watches. The photo on the right shows two other researchers crouched on a steep, sandy slope next to a band of brown rocks.
Text: Paleontologists, who study fossils, record the types of life forms found in each rock layer, and their abundance. These lines of evidence help us understand how ecosystems were affected in response to changes in the atmosphere and climate.
In Blacks Canyon of Zion National Park, Dr. Celina Suarez and her team discovered the chemical signatures of the End Triassic Extinction. This major discovery supports evidence found by scientists around the world that the Triassic Extinction was driven by rapid release of the greenhouse gas carbon dioxide (CO2) into the atmosphere.
Description: The bottom-right corner of the exhibit panel is taken up by a photo of colorful foothills made of orange, pink, and white rock. Two tiny people are visible standing towards the top of a steep hill. Above these hills are horizontal bands of red orange stone that form a cliff against the blue sky above. At the base of this formation is scrubland of sagebrush, juniper trees, and other plants.
Text: Scientists of all kinds work together to improve our knowledge of global ecosystems using the most up-to-date techniques to gather evidence and check each other’s work. Together, we can use evidence to better understand how our world works, and how ecosystems respond to sudden changes in Earth’s atmosphere.
Our world is a complex puzzle and researchers are vital to finding and connecting pieces that reveal the bigger picture. By working together, we can all contribute to a better understanding of nature.
Description: A green, illustrated magnifying glass labeled, “Junior Paleontologist” highlights a purple QR code.
Text: Hey Jr. Rangers! Looking to learn more? You can discover, learn about, and protect park fossils by downloading your own Jr. Paleontologist activity book! Scan the QR code above to visit go.nps.gov/ZionPaleontologist
Description: A white band at the bottom of the panel contains two logos. The first is a blue globe surrounded by gold spokes like a sun. In the center are the letters “NSF”. The second logo is an orange circle with the letter “Z” in the middle, which is cut in half by an infinity symbol.
Text: Thank you. Funding for this research was provided by the National Science Foundation, and this exhibit was made possible through Zion Forever Project.
This replica skull includes all of Angistorhinus' sharp teeth!
NPS/Abi Farish
This phytosaur, found in the Chinle Formation just outside of Zion National Park, is called Angistorhinus. Its long narrow snout and conical teeth suggest it was well adapted for eating fish, similar to today’s narrow-snouted crocodiles and gharials. The back of Angistorhinus’ jaws are powerful and equipped with large, blade-like teeth, indicating that it may have specialized towards preying on specific animals. The total length of this animal is estimated at 15-18 feet (5-6 meters) long.
Brian Engh
Angistorhinus: phytosaur
Phytosaurs are groups of early reptiles that look like modern crocodiles but are unrelated. They hunted in the rivers of the Triassic about 50 million years before the first true semiaquatic crocodiles appeared in the Early Jurassic.
Skull on top
Angistorhinus Triassic phytosaur. Chinle Formation approximately 220 million years ago. Skull viewed from above. Photos by Andrew Milner, St. George Dinosaur Discovery Site.
Skull on bottom
Calsoyasuchus early Jurassic crocodile. Kayenta Formation approximately 190 million years ago. Skull viewed from above.
Notice how phytosaur nostrils are close to their eyes, while crocodiles have nostrils at the tip of the snout. The position of the nostrils is one of the major skeletal differences between phytosaurs and crocodiles. Can you spot any other differences?
ETE - Phytosaur audio description
Audio description of the Phytosaur display in the End Triassic Extinction exhibit
Description: On the display table of this exhibit is a reddish-tan replica of a phytosaur skull. It is 4 feet (1.2 meters) long and 18 inches (46 cm) tall. Half the skull is a long, narrow snout full of pointed yellow teeth. The skull has several round holes on either side of the head, and two thin nostrils at the top. On either side of the skull are signs advising, “No Touching.”
Text: This phytosaur, found in the Chinle Formation just outside of Zion National Park, is called Angistorhinus (pronounced: an-gee-store-eye-nus). Its long narrow snout and conical teeth suggest it was well adapted for eating fish, similar to today’s narrow-snouted crocodiles and gharials. The back of Angistorhinus’ jaws are powerful and equipped with large, blade-like teeth, indicating that it may have specialized towards preying on specific animals. The total length of this animal is estimated at 15-18 feet (5-6 meters) long.
Description: A digital illustration of two large reptiles lying on light pink sand. The reptiles have long, narrow snouts full of sharp, pointed teeth. One animal rests the end of its snout on the other’s back. Their skin is light brown and green, with patches of red on their heads and spiked backs. At the top of their head are small yellow eyes, which sit on either side of their skulls just above their long, thin nostrils. Three tiny, long necked animals stand on the back of one phytosaur.
Text: Angistorhinus (pronounced: an-gee-store-eye-nus): phytosaur. Phytosaurs are groups of early reptiles that look like modern crocodiles but are unrelated. They hunted in the rivers of the Triassic about 50 million years before the first true semiaquatic crocodiles appeared in the Early Jurassic.
Description: Below this text are two photos of skulls viewed from above. The skull on top has a long, narrow snout with a rounded end. The head has two long nostril holes (nares) close together, with similarly shaped eye sockets (orbits) just above them on either side of the top of the head. All four holes are outlined with white ink to easily distinguish their shape.
Text: Angistorhinus (pronounced: an-gee-store-eye-nus) Triassic phytosaur. Chinle Formation approximately 220 million years ago. Skull viewed from above. Photos by Andrew Milner, St. George Dinosaur Discovery Site.
Description: The next skull has a wider, triangular snout with a rounded tip. At the tip are two round nostrils (nares) close together, outlined in white ink to show their shape. The head is wider than the previous skull, and less rounded. Two large, round eye sockets (orbits) are at the top of the head closely separated by a strip of bone. These holes are also outlined in white ink to define their shape.
Text: Calsoyasuchus (pronounced: Kal-so-ya-soo-kus) early Jurassic crocodile. Kayenta Formation approximately 190 million years ago. Skull viewed from above.
Notice how phytosaur nostrils are close to their eyes, while crocodiles have nostrils at the tip of the snout. The position of the nostrils is one of the major skeletal differences between phytosaurs and crocodiles. Can you spot any other differences?
Description: To the right of this text is a green illustration of a magnifying glass that reads “Junior Paleontologist” on the handle.
Fossil displays - photos coming soon
Fossil fish bones. Coelacanth and semionotid. Moenave Formation Zion 47000.
Fossil fish scales. Semionotus kanabensis. Moenave Formation. Zion 592.
Petrified wood of a conifer tree. Coniferophyta. Moenave formation. Zion 595.
Therapod dinosaur footprint and burrow traces. Grallator sp. Moenave Formation. Zion 43032.
ETE - Fossils audio description
Audio description of the fossils displayed at the End Triassic Extinction exhibit
Description: Inside the glass exhibit case are 7 fossils.
Text: Fossil fish bones. Coelacanth (pronounced: seal-oh-canth) and semionotid (pronounced: sem-ee-oh-not-id). Moenave Formation Zion 47000.
Description: The first fossil is a thin line of bone in a square-shaped rock. To its right is an oval-shaped fossil protruding from a flat white rock. Next is a larger stone with the fossilized head and jawbone of a fish. The final fish fossil is a stone with two thumb-sized protrusions of rock.
Text: Fossil fish scales. Semionotus kanabensis (pronounced: sem-ee-oh-not-us can-ab-en-sis). Moenave Formation. Zion 592.
Description: A flat shard of rock sitting with a fossilized shiny orange fish scale, about the size of a fingernail.
Text: Petrified wood of a conifer tree. Coniferophyta (pronounced: con-if-arrow-fight-uh). Moenave formation. Zion 595.
Description: A long grey rock surrounds a mineralized brown segment of a tree branch. The texture of its bark is preserved on the surface.
Text: Therapod dinosaur footprint and burrow traces. Grallator sp. Moenave Formation. Zion 43032.
Description: A large square stone covered in three and four toed dinosaur footprints.
Zion National Park
1 Zion Park Blvd.
Springdale,
UT
84767
Phone:
435-772-3256
If you have questions, please email zion_park_information@nps.gov.
Listen to recorded information by calling anytime 24 hours a day.
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