Formation of the Colorado Plateau

  1. Tectonic Activity: The Colorado Plateau's formation began around 300 million years ago during the late Paleozoic Era. Tectonic forces caused the region to uplift due to the collision of tectonic plates. This uplift was not uniform, leading to its elevated landscapes.

  2. Erosion: Over the ensuing millions of years, erosion by wind, water, and ice shaped the plateau. Rivers carved deep canyons, such as the Grand Canyon, and wind exposed various layers of sedimentary rock. Erosional processes helped reveal the different rock strata that tell the story of the area’s geological history.

  3. Sedimentary Layers: The Colorado Plateau consists of various sedimentary rock layers that were deposited over millions of years. The primary rock layers, in chronological order, include:

    • Navajo Sandstone: Formed about 200 million years ago during the Jurassic Period from ancient sand dunes.

    • Kayenta Formation: Also from the Jurassic Period, this layer represents a floodplain environment with a mix of sand and silt, where early dinosaurs roamed.

    • Wingate Sandstone: This layer consists of more sand deposits from ancient dunes and is also Jurassic in age.

    • Chinle Formation: From the Late Triassic, containing mudstone and sandstone, this formation is significant for its rich fossil record.

Dinosaurs on the Colorado Plateau

The dinosaurs that existed in the various layers of the Colorado Plateau adapted to changing environments over millions of years. Specific formations within the plateau provide important fossil evidence of these creatures:

  • Navajo Sandstone: Although direct dinosaur fossils are rare in this layer, it provides evidence of the ecosystems that existed during the time, characterized by dunes and desert habitats.

  • Kayenta Formation: This layer is notable for fossils of early dinosaurs, including the remains of Agnosphitys and Dilophosaurus, which thrived in a lush, floodplain environment.

  • Wingate Sandstone: Fossils are scarce here, but this layer indicates the presence of large herbivorous dinosaurs like Apatosaurus and Stegosaurus, which would have roamed the area.

  • Chinle Formation: This layer is rich in fossils including those of Coelophysis, a small theropod dinosaur. The Chinle Formation represents a more diverse ecosystem where dinosaurs coexisted with early mammals, reptiles, and amphibians.

Fossil Examples

  1. Dilophosaurus: Fossils found in the Kayenta Formation provide insights into this early dinosaur’s structure and ecological role.

  2. Coelophysis: Fossils from the Chinle Formation show a lightweight, carnivorous dinosaur that likely fed on small animals, featuring in a diverse Late Triassic ecosystem.

  3. Apatosaurus: Fossils of this massive herbivore indicate that the Colorado Plateau was once home to large sauropods during the late Jurassic.

Conclusion

The Colorado Plateau serves as a geological and paleontological treasure trove, revealing a dynamic history through its rock layers. These layers not only tell the story of the Earth's geological past but also provide a snapshot of the ecosystems that existed at various times, showcasing the dinosaurs that roamed the area. The continued study of these formations aids in understanding the evolution of life on Earth and the processes that shaped the natural world we see today.


Where To Best See good examples of Geology in St. George:

  1. Zion National Park:

    • Zion Canyon Scenic Drive: Look for the prominent rock layers exposed in the canyon walls, particularly around the Court of the Patriarchs. You can observe the tilted and folded sedimentary layers that indicate past tectonic activity, as well as the transition between different rock types.

    • Observation Point: From this viewpoint, you can see the results of erosion along fault lines. The dramatic cliffs show layers of Navajo Sandstone that have been shaped by geological forces. The contrast between the cliffs and the valley provides excellent context for understanding fault processes.

  2. Snow Canyon State Park:

    • Johnson Canyon Trail: As you hike, keep an eye out for the fractures and joints in the rock formations, as well as evident layers of lava rock that have flowed from volcanic activity. You may spot areas where the geological strata appear displaced, indicating past fault movements.

    • West Canyon Road: Along the drive, you can observe the smooth and jagged edges of the cliffs, showcasing different layers of rock stacked upon one another. The varied colors and textures also show how the area has changed over time due to geological forces.

  3. Red Cliffs Desert Reserve:

    • East Gateway Trailhead: The trails here provide views of striking red and white sandstone formations. Look for evidence of rift structures and normal faults that have shaped the terrain over millions of years.

    • Red Cliffs Campground: Walk around the campground to see exposed rock formations showing clear fault lines or fractures. There can be layers of sedimentary rock that have been pushed or pulled apart due to tectonic forces.

  4. Hurricane Fault Zone:

    • State Route 9 (Hurricane Area): Along this route, pay attention to the marked pull-off areas that discuss geological features. Look for bends in the road and stabilize areas that might showcase offsets in rock layers along the fault line. In some areas, you may see clear evidence of lateral fault movements.

  5. Dinosaur Trackways:

    • The Footprints Site: Look for the preserved tracks of dinosaurs embedded in the limestone, which often occurs in sedimentary rock layers impacted by geological shifts. While viewing the tracks, consider the geological context of how movements in the earth shaped the landscape.

  6. Local Geology Tours:

    • Consider specific tours that focus on geology, where guides often highlight visible fault lines, rock formations, and fracture patterns in the landscape. They can lead you to some lesser-known spots where you can see fault lines more clearly.

The geology of the United States is incredibly diverse, shaped over billions of years by a combination of tectonic activity, volcanic eruptions, sedimentation, and erosion. Here is a condensed overview focusing on the key events up to the formation of the Colorado Plateau:

1. Precambrian Era (Before 541 million years ago):

  • Formation of the Earth: The geological history of the U.S. began with the formation of the Earth approximately 4.6 billion years ago. During the Precambrian era, much of what is now the United States was part of ancient continental landmasses.

  • Shield Rocks: The oldest rocks found in the U.S. are part of the Canadian Shield, extending into northern regions. These rocks formed from ancient igneous and metamorphic processes.

2. Paleozoic Era (541 - 252 million years ago):

  • Sedimentation: This era saw significant sedimentation in shallow seas that covered parts of North America. The landscapes were characterized by limestone, sandstone, and shale deposits.

  • Mountain Building: Toward the end of the Paleozoic, tectonic forces led to the formation of the Appalachian Mountains due to the collision of the North American Plate with other landmasses.

3. Mesozoic Era (252 - 66 million years ago):

  • Age of Dinosaurs: This era was marked by the dominance of dinosaurs and significant geological changes. The Western United States saw the uplift of the Rocky Mountains.

  • Sedimentation in the Interior: Large deserts and inland seas existed, resulting in a variety of sedimentary rock formations, including the famous Navajo Sandstone, which formed from ancient dune fields.

4. Laramide Orogeny (Late Mesozoic to Early Cenozoic, about 70 - 40 million years ago):

  • Mountain Building: This period was characterized by the Laramide Orogeny, which caused significant uplift in the Rocky Mountains and the surrounding regions, particularly in Colorado and Utah.

  • Formation of High Plateaus: The Colorado Plateau began to uplift during this time, creating the flat-topped plateaus and deep river canyons that are characteristic of the region today.

5. Creation of the Colorado Plateau (Cenozoic Era, 66 million years ago - Present):

  • Tectonic Uplift: The Colorado Plateau was formed through a combination of tectonic uplift and volcanic activity. The uplift exposed the sedimentary layers that had built up over millions of years in the area.

  • Erosion and Landscape Formation: Erosion by rivers, particularly the Colorado River, carved out canyons and left behind distinct geological features like the Grand Canyon, Monument Valley, and the numerous mesas and buttes.

Conclusion

The creation of the Colorado Plateau is a culmination of extensive geological processes, characterized by sedimentation, volcanic activity, and tectonic uplift. This process not only shaped the Plateau itself but also established the diverse geological features found throughout the United States, contributing to the country's rich natural heritage.

Best Places To See Geology

Quail Creek Reservoir Geology Overview

Quail Creek Reservoir, located in southern Utah near St. George, is surrounded by unique and striking geological features characteristic of the Colorado Plateau and the Basin and Range Province. The reservoir itself is a man-made lake created by the damming of Quail Creek, primarily for water storage and recreational purposes. The surrounding area showcases diverse geological formations, including colorful sandstone cliffs, volcanic rock, and ancient river channels, shaped by millions of years of geological processes.

How It Formed

  1. Sedimentary Rocks: The predominant geological formations around Quail Creek Reservoir are sedimentary rocks, primarily sandstone, and limestone. These rocks were formed from sediments deposited in ancient rivers, lakes, and deserts during the Mesozoic and Cenozoic eras. Over time, layers of sediment compacted and cemented to form rock.

  2. Volcanic Activity: The region is also influenced by significant volcanic activity that occurred millions of years ago. Volcanic rock formations, such as basalt, can be found around the reservoir, resulting from lava flows and eruptions in the area.

  3. Erosion and Weathering: The current landscape has been shaped by erosion and weathering, which sculpted the existing rock formations over time. The interplay of water, wind, and ice has exposed different layers of rock, creating dramatic cliffs, canyons, and valleys around the reservoir.

Interesting Facts

  1. Colorful Rock Layers: The geology around Quail Creek Reservoir features vibrant colors ranging from deep red and orange sandstone to lighter beige and white limestone. These colors result from the mineral composition of the rocks and can change dramatically depending on the time of day and the angle of sunlight, creating stunning photographic opportunities.

  2. Habitat Diversity: The geological features surrounding the reservoir create diverse habitats for various plant and animal species. The area supports desert flora and fauna, as well as aquatic ecosystems within the reservoir itself, making it an excellent location for birdwatching and wildlife observation.

  3. Paleontological Significance: Like other areas in southern Utah, the region around Quail Creek Reservoir holds potential for paleontological discoveries. Fossils of ancient marine life and dinosaurs have been found in the sedimentary layers, providing insight into the prehistoric environment and the types of life that existed millions of years ago.

Quail Creek Reservoir not only serves recreational needs but also offers a window into the complex geological history of the region, making it a fascinating destination for geology enthusiasts and nature lovers alike.

Quail Creek Reservoir

Glitter Mountain Geology Overview

Glitter Mountain is a striking geological feature located near St. George, Utah, notable for its sparkling mineral deposits that reflect sunlight, giving the mountain its name. The area is primarily composed of volcanic rock and is a part of the surrounding geological formations that make up the region’s varied landscape. You can dig for your own rocks here!

The owners prefer that people do not go down into the pit, but as long as you use common sense and stay safe, it is okay. Of course, make sure you stay away from any machinery when they are mining.

When we visited, we did not go down into the pit and instead walked around the outside. There was so much selenite on the ground outside of the pit that we didn’t feel the need to go down into it.

We started seeing pieces as soon as we got out of the car!

Bring plenty of water, especially if visiting during the hotter months. There’s no shade.

First of all, there IS an active mining claim on Glitter Mountain, so make sure you read and follow the posted signs when you arrive.

The Feller Stone family holds the claim and has the exclusive right to remove the selenite for commercial sales. They ask first and foremost that you use common sense when visiting the site and use caution around the pit area.

There’s no fee to visit the site, but the owners ask that people pay for any selenite that they take home. There’s a sign on site with pricing information for paying through PayPal or Venmo. We had service out there, so it was really easy to send the money on-site.

It is okay to bring a small hammer, chisel, (or garden tools), and a bucket. They do not allow “mining”, power tools, or heavy digging.

If you plan to use a hammer or chisel or do some light digging, I highly recommend a pair of safety glasses. They’re cheap and a good idea to have on hand if you’re digging around. You can find them easily at hardware stores or on Amazon.

How They Formed

  1. Volcanic Activity: Glitter Mountain is primarily composed of volcanic materials, including basalt and other igneous rocks. These volcanic rocks were formed from lava that erupted from ancient volcanoes in the region. Through various volcanic activities, including explosive eruptions and lava flows, these materials accumulated and solidified over millions of years.

  2. Mineral Deposits: The sparkling appearance of Glitter Mountain is due to the presence of various minerals, particularly certain types of quartz and other reflective minerals that form in volcanic environments. As magma cooled and crystallized, these minerals were formed, contributing to the unique sheen of the mountain's surface.

  3. Erosion and Weathering: Over time, erosion and weathering processes have exposed the surface of Glitter Mountain, revealing the shiny mineral deposits. Wind, rain, and temperature fluctuations gradually wear down the rock, leading to the distinct geological features seen today.

Interesting Facts

  1. Unique Sparkling Appearance: Glitter Mountain gets its name from the significant presence of glittering minerals like mica and quartz. From a distance, the mountain appears to shimmer, especially in sunlight, making it a visually stunning landmark that attracts photographers and nature lovers.

  2. Mining History: The area around Glitter Mountain has a history of mining activity, particularly for minerals. The presence of valuable minerals, such as gypsum and other deposits, has drawn attention for potential extraction, influencing the local economy and geology studies.

  3. Cultural Significance: Glitter Mountain holds cultural significance for local Native American tribes and the surrounding communities. It is often considered a landmark and a point of interest in local folklore and history, adding to its value beyond geology.

Glitter Mountain not only serves as a fascinating geological site but also embodies the natural beauty and rich history of the region, making it a compelling destination for visitors exploring the southern Utah landscape.

Nearby Glitter Mountain is the Little Black Mountain Petroglyph Site.

This is a great stop if you have time for a little detour. There’s a nice walking path to various petroglyphs on the rocks representing 6,000 years of human habitation and use in the area.

Glitter Mountain

Glitter Mountain Geology Overview

Glitter Mountain is a striking geological feature located near St. George, Utah, notable for its sparkling mineral deposits that reflect sunlight, giving the mountain its name. The area is primarily composed of volcanic rock and is a part of the surrounding geological formations that make up the region’s varied landscape. You can dig for your own rocks here!

The owners prefer that people do not go down into the pit, but as long as you use common sense and stay safe, it is okay. Of course, make sure you stay away from any machinery when they are mining.

When we visited, we did not go down into the pit and instead walked around the outside. There was so much selenite on the ground outside of the pit that we didn’t feel the need to go down into it.

We started seeing pieces as soon as we got out of the car!

Bring plenty of water, especially if visiting during the hotter months. There’s no shade.

First of all, there IS an active mining claim on Glitter Mountain, so make sure you read and follow the posted signs when you arrive.

The Feller Stone family holds the claim and has the exclusive right to remove the selenite for commercial sales. They ask first and foremost that you use common sense when visiting the site and use caution around the pit area.

There’s no fee to visit the site, but the owners ask that people pay for any selenite that they take home. There’s a sign on site with pricing information for paying through PayPal or Venmo. We had service out there, so it was really easy to send the money on-site.

It is okay to bring a small hammer, chisel, (or garden tools), and a bucket. They do not allow “mining”, power tools, or heavy digging.

If you plan to use a hammer or chisel or do some light digging, I highly recommend a pair of safety glasses. They’re cheap and a good idea to have on hand if you’re digging around. You can find them easily at hardware stores or on Amazon.

How They Formed

  1. Volcanic Activity: Glitter Mountain is primarily composed of volcanic materials, including basalt and other igneous rocks. These volcanic rocks were formed from lava that erupted from ancient volcanoes in the region. Through various volcanic activities, including explosive eruptions and lava flows, these materials accumulated and solidified over millions of years.

  2. Mineral Deposits: The sparkling appearance of Glitter Mountain is due to the presence of various minerals, particularly certain types of quartz and other reflective minerals that form in volcanic environments. As magma cooled and crystallized, these minerals were formed, contributing to the unique sheen of the mountain's surface.

  3. Erosion and Weathering: Over time, erosion and weathering processes have exposed the surface of Glitter Mountain, revealing the shiny mineral deposits. Wind, rain, and temperature fluctuations gradually wear down the rock, leading to the distinct geological features seen today.

Interesting Facts

  1. Unique Sparkling Appearance: Glitter Mountain gets its name from the significant presence of glittering minerals like mica and quartz. From a distance, the mountain appears to shimmer, especially in sunlight, making it a visually stunning landmark that attracts photographers and nature lovers.

  2. Mining History: The area around Glitter Mountain has a history of mining activity, particularly for minerals. The presence of valuable minerals, such as gypsum and other deposits, has drawn attention for potential extraction, influencing the local economy and geology studies.

  3. Cultural Significance: Glitter Mountain holds cultural significance for local Native American tribes and the surrounding communities. It is often considered a landmark and a point of interest in local folklore and history, adding to its value beyond geology.

Glitter Mountain not only serves as a fascinating geological site but also embodies the natural beauty and rich history of the region, making it a compelling destination for visitors exploring the southern Utah landscape.

Nearby Glitter Mountain is the Little Black Mountain Petroglyph Site.

This is a great stop if you have time for a little detour. There’s a nice walking path to various petroglyphs on the rocks representing 6,000 years of human habitation and use in the area.