Utah
Type |
Symbol |
Year Est. |
---|---|---|
State Rock |
Coal |
1991 |
State Mineral |
Copper |
1994 |
State Gem |
Topaz |
1969 |
State Fossil |
Allosaurus
|
1988 |
State Rock: Coal
Coal is a type of sedimentary rock that has a very high organic content. It is made up of prehistoric plant material that has slowly been compressed over time forming thin layers ranging from millimetres to several tens of meters thick. The large amount of plant material typically occurred in prehistoric swamps. Over time the plant material died and accumulated in the water. There was so much dead plant material in the water that there wasn't enough oxygen to cause plant decay, leaving the plant material behind to eventually be covered up by sediment as the swamp was slowly transformed into a different environment (i.e. beach, floodplain, lagoon, etc.). Coal is typically composed of mostly all carbon (50-98%), hydrogen (3-13%), and oxygen, with varying amounts of nitrogen, sulphur, and other elements. Because of the high organic content, coal is an ideal combustible and has been used for centuries as a heat and fuel source. There is a range of types of coal depending on how long the plant material has been "cooked", a process that involves compaction of the plant material, how high the temperature had gotten, and how long it was heated for. The type of coal also depends on the original plant materials that had been compacted to form the coal. By degree of cooking the ranks of coal are: peat (essentially pre-coal), lignite (brown coal, low temperature cook, carbon content 60-70%), bituminous ("soft coal" and the most abundant, has a higher temp of cooking, 71-87% carbon), and anthracite (technically a metamorphic variety of coal that has >87% carbon, considered "hard coal").
State Mineral: Copper
Copper is an elemental metal mineral, meaning that it is entirely composed of one element; copper (Cu) in this instance. It is also the only elemental metal, besides gold, which is not naturally silver or grey. Copper is the oldest known metal to have been manipulated by humanity. The Copper Age took place after the Neolithic (Stone) Age, and lasted from ~4500 BC to ~3500 BC, overlapping with the early Bronze Age. The earliest known Middle Eastern artifact is also made of copper, a pendant dating back to 8700 BC. In the modern day, copper is the third most consumed industrial metal in the world. Mining of copper in the US began with high grade ore deposits found in Arizona and Michigan in the late 1800's, however newer processes that were able to filter the copper out of low-grade deposits made excavating low-grade ores more economical, leading to more abundant uses of strip and open-pit mining for the recovery of copper. These processes enabled the US to become one of the leading producers of copper in the world.
Related: Arizona State Metal - Copper
State Gem: Topaz
State Fossil: Allosaurus
References
https://statesymbolsusa.org/states/united-states/utah
Geology of Utah's National Parks
Through Pictures
(at least the one's I have been to)
Glen Canyon National Recreation Area
Golden Spike National Historic Site
Natural Bridges National Monument
Timpanogos Cave National Monument
National Parks visited but I have no pictures (at this time) to do a geology post
(link directs to NPS site)
Cedar Breaks National Monument
Visted in 2011 and 2019
Following our visit to Canyonlands we hit up Arches National Park for a quick visit. We had done most of Arches already back in 2011 but we figured it would be a fun place to get a quick hike in. Out of the five National Parks in Utah, Arches may be the most popular because of the fantastic geological structures and the extremely close distance to Moab, a popular tourist town in the area. The pictures below are a combination of both previous trips.
The entrance sign shot.
In order to get into Arches, you must switchback up this rather steep road initially from the main entrance. Here is a shot from the top of the entrance road looking down on the main entrance/visitor's center.
Arches National Park is another park within the Colorado Plateau region of North America, where the ground has been forced upwards. Because of this the upper layer of rocks have a tendency to have a lot of erosion and cracking within the rock layers. Within Arches, the dominant rock formation is known as the Entrada Sandstone, a Jurassic age (~150 million years old) sandstone, formed from a coastal dune environment. There are a ton of geological erosional features throughout the park and I will highlight few of them. Here is an area shortly upon entering the park known as Park Avenue.
Here is a precariously balanced rock within the Park Avenue area.
Within the central part of the park is a fantastic congregation of arches, all within a very short hike. Here are two arches attached to each other with the larger arch known as Turret Arch. The structures in Arches National Park formed from the process of erosion. Over time, erosion widened the cracks that had formed during the uplift of the region. These cracks, or joints, created long, parallel breaks in the rocks called fins.
Turing around from Turret Arch are two very large arches, known as the Window Arches. This is the South Window, with the North Window to the right out of frame. Not only does water erode the outside of the rock but water soaks into the rock itself. The Entrada Sandstone is very porous, allowing for the rain water to easily soak into the rock. As the water filters its way down into the sandstone it eventually reaches the base of the sandstone at the contact with the lower rock unit, the Carmel Formation. The Carmel Formation is a slightly older, Jurassic age, series of mudstones, siltstones, and sandstones, formed in a tidal flat environment. The much higher percentage of mud prevents water from flowing through it, so as the water flows through the Entrada, it eventually pools at the base of the sandstone on top of the Carmel Formation.
The cement in the Entrada Sandstone is one of the key ingredients. Many sandstones are cemented by silica, which is basically a dissolved type of quartz, a very hard mineral. Those types of sandstones are incredibly difficult to erode. The Entrada Sandstone, however, is cemented with calcite, a mineral that easily dissolves in slightly acidic water, such as the calcite in caves. As the water sits at the base of the Entrada, it slowly dissolves away the calcite cement. Then as the water freezes and thaws over the winter months, the expansion and contraction of the water breaks apart the rocks and carries away the sand. Leaving an ever widening hole at the base of the rock formation.
Within the same area we have my favorite set of arches in the whole park, Double Arch. Here is a view across the parking lot. Eventually, as more material erodes away, these holes are widened over time, creating thinner and thinner pieces of overarching rocks, that will eventually erode away all together.
Here is a view of the Double Arch from underneath. The formation of these arches is a precarious balance between too much and not enough water though. Even though you want water to dissolve the cement and carry away the sand, too much rain would erode these formations way too quickly. This region only gets 8-10 inches of rain a year, making this a desert, and also providing just enough water to slowly break down the rocks. The erosion of the arches is so fantastic that it can leave behind these thin bands of stone, until eventually erosion will make the stone too thin to support itself and eventually will collapse.
Perhaps the most famous arch in the park is Delicate Arch. There are two ways to see Delicate Arch. Either you can do the harder, and longer, hike to the arch itself. Unfortunately, we were unable to do that, so we opted for the shorter and easier hike to the overlook.
Here is one of the more famous formations, Balanced Rock. Besides just the arches there are other geological erosional features such as this. Here more resistant rocks overly softer rocks. The Entrada Sandstone is the large bolder sitting upon a pedestal of the softer Carmel Formation, described above. Since the Carmel Formation is a softer rock, it erodes away easier than the Entrada Sandstone, creating features like this.
Distant view of some more geological formations.
View of the Courthouse Towers.
References
https://www.nps.gov/arch/learn/nature/arches.htm
Visited in 2009
Bryce Canyon is one of Utah's most famous National Parks and it is truly a beauty to behold. While we were there we ended up doing one of the trails where you can hike down amongst the hoodoos, which I highly recommend.
Doing the entrance sign shot before it became routine.
Bryce Canyon, much like the other nearby National Parks including Zion National Park and Grand Canyon National Park, are part of the Colorado Plateau. This is a large area covering the four corners region where the rocks have been severely forced vertically upwards. And like those nearby parks, Bryce Canyon covers a large range of geological formations, however there really is only one formation that is the star of the show here; the Claron Formation.
The Claron Formation forms the Pink Cliffs part of Bryce Canyon and is broken up into two individual members: the Pink Limestone Member, which forms the reddish hoodoo rocks of the Pink Cliffs, and the slightly younger White Limestone Member, which is right on top of the Pink member seen here along the rim of the canyon in the distance.
The White and Pink Limestone Members of the Claron Formation were deposited during the Eocene Period, approximately 60 to 50 million years ago. During that time, this part of Utah was covered by a vast lake, depositing thick layers of calcite that eventually consolidated into limestone. The Claron Formation also includes beds of siltstone and dolostone (like limestone but with dolomite instead of calcite). Limestone is also the same rock that caves form in because they dissolve in slightly acidic water.
Bryce Canyon is located at such an elevation that the temperature fluctuates above and below freezing frequently within the same day. In fact, it fluctuates across the freezing point more than 200 days a year.
One of limestone's properties is that it has a tendency to crack along parallel lines, called joints. When the cracks start to form within the limestone, water then is able to seep into those cracks. Water seeps into the cracks during the warmer days then freezes during the colder nights. This expansion of the water creates what is known as "ice wedging", which physically pushes the rock pieces apart.
Eventually the ice wedging slowly breaks the edges of these cracks enough for pieces to start to break off. Over time the vertical, parallel cracks start to widen leaving behind these pinnacles of rock. These are the structures known as hoodoos. If you know anything about caves as well, you know that most cave formations have a smooth surface due to the water dissolving the calcite in the rocks and redepositing it as cave formations. That same dissolution is happening here, which gives the hoodoos their smooth surface appearance, as compared with the more rough and angular arches at Arches National Park.
Different layers within the limestone erode at different paces, especially along the bedding planes, creating these balancing rock structures and hoodoos that have thicker and thinner parts.
But overall they provide the viewer with a beautiful effect during a lovely hike amongst the hoodoos as well as overlooking from above.
The cracks within the limestone have become large enough that rather steep valleys are all that remains of the rocks in this area. And since the valleys now concentrate the water, the valleys are where the most erosion occurs, further emphasizing the already steep valleys.
Looking up one of the narrow valleys with a bridge of limestone still connecting various pieces, or more likely, a fallen hoodoo.
View across the hoodoos from near the end of our hike. The red coloration is due to a large percentage of iron and oxygen within the limestone when it was deposited, creating rust. The upper White Limestone Member had much less oxygen and/or iron when it was deposited, leaving behind a stark white rock. The differences in the coloration throughout the Pink Limestone Member are due to the variations of the amounts of iron and oxygen during initial deposition.
Here is an overlook into the surrounding valley, off into the older rock units surrounding Bryce. The White Limestone Member can be seen to the left of the photo as well.
References
https://www.nps.gov/articles/nps-geodiversity-atlas-bryce-canyon-national-park.htm
http://www.zionnational-park.com/bgeology.htm
https://www.nps.gov/brca/learn/nature/hoodoos.htm
Visited in 2019 and 2020
Canyonlands is one of Utah's big 5 National Parks, and probably the least visited of all of them. The park consists of three distinct districts, Island in the Sky, The Needles, and The Maze. All three districts are time consuming to get to and at least a couple of hours drive between each one. We ended up hitting up Canyonlands in two separate trips, visiting Island in the Sky district in 2019 and the Needles district in 2020. The districts are distinctly divided by the Green and Colorado Rivers, with the confluence of the rivers forming a "Y" shape. The top middle of the Y is the Island in the Sky, the right of the Y is the Needles, and the left is the Maze.
The first stop was the Island in the Sky district and here is the entrance sign from there.
Here is a great display from the Island in the Sky Visitor's Center showing the rock units across the canyons and some information from each rock unit. Canyonlands, like its neighbor parks, sits within the Colorado Plateau. This is an area of the United States encompassing the Four Corners region, and surrounding areas, where the ground is being pushed upwards. This causes a great increase in elevation of the land surface, and when the land surface is being pushed up, rivers erode downwards at an increased rate. The area has rocks that cover a tremendous range of ages and these pictured here are only a small portion of everything in the region. At the bottom and the top, the Organ Rock Shale is Permian in age, ~270 million years old, to the Navajo Sandstone, which is Jurassic in age, ~180 million years old.
We are usually limited to one relatively easy hike per day, due to physical limitations, and for this trip we decided on Whale Rock. Whale rock is a dome of Navajo Sandstone. The Navajo Sandstone is a preserved prehistoric desert that used to cover large parts of the American west. The reason that geologists know that the Navajo Sandstone was a prehistoric dune is because of the prominent cross bedding located within the beds. Cross bedding preserves the internal structures of sand dunes. Whale Rock is the rock we are currently standing on top of, after having completed the hike, looking towards the southwest.
View from the top of Whale Rock looking towards the south, a bit to the left of the above photo.
A panorama to the right of the above shots looking more to the southwest. This is a long distance shot of what is known as Upheaval Dome.
After leaving Whale Rock we traveled down the road to get a closer look at Upheaval Dome. Here is a close up view looking down into the eroded dome from the same direction as the picture above, only much closer. Upheaval Dome is a mystery. Here all of the rocks are bent upwards towards a peak, that has since been eroded away. This is what is known as a dome. But how did it form? There are two theories. One is that there used to be a layer of salt under the ground from a prehistoric basin (like the Bonneville Salt Flats). Then other rocks were deposited on top of the salt layer. Over time the salt got squished upwards into the mushroom shape, distorting the rocks around it.
Another, and the more popular theory, is that this is the site of a prehistoric meteorite impact. When the meteorite struck the surface everything was forced downward initially, but then the rocks rebounded from the impact, causing everything to be pointed upwards. The reason the dome is now a "basin" is because as the rocks are bent, the rocks at the top portion of the dome crack. These cracks consolidate the water, restricting the erosion to these areas. Eventually the dome becomes a basin as the rocks are washed away.
What is known, though, is that this is a mishmash of rocks at the base of the dome with the White Rim Sandstone, a Permian desert deposit, is mixed up and faulted with the overlying Moenkopi Formation, a series of interbedded sandstones, siltstones, and shales from a Triassic tidal flat environment. The upper cliff edge is the Wingate Sandstone, another Jurassic desert sandstone, a little older than the overlying Navajo Formation, with the Chinle Formation in between, forming the slopes of the canyon walls. The Chinle Formation is also Triassic in age and represents a wide variety of interbedded rock units (sandstone, conglomerate, siltstone, shale) from river and lake deposits.
View of the Wingate Sandstone (I believe), showing the cross bedding in the distance. The rock units themselves are deposited horizontally here, while the cross bedding is the angled lines through the units. These are formed from sand, as it is pushed over the dune crest and rolls down the leeward side, or slipface. This creates an ordered layer of sand on the slipface side of the dune and that is what is preserved as cross bedding. This rock unit is topped by the Kayenta Formation, which divides the Navajo Sandstone from the Wingate Sandstone. The Kayenta Formation is a Jurassic age series of sandstones, shales, and limestones from a meandering river environment that frequently preserves dinosaur tracks.
A bit further to the south is the Grand View Point, here looking towards the west. Off in the distance is the Green River canyon, which eventually joins up with the Colorado River to the left of this picture.
The view towards the southeast from the Grand View Point, overlooking the Colorado River canyon in the distant. The confluence of the Green and Colorado Rivers is towards the right in this picture.
This is a display showing the features from the above picture. The cliff edges are created from more resistance rock overlying softer rock. Typically in this region that means sandstones are the more resistant rocks. Currently, I am standing on a sandstone layer within the Kayenta Formation, while the edge and flatter region before the main canyon down below is the White Rim Sandstone.
View from Grant View Point looking towards the Confluence of the Green and Colorado Rivers. The steep cliff faces here are made up of the Wingate Sandstone.
On the way out of the Island in the Sky district we stopped at the Shafer Canyon Overlook. Here is a view of Shafer Canyon looking down on the rather steep Shafer Trail Road switchbacking down the canyon walls. From here we headed to Arches during the 2019 trip but we came back to Canyonlands in 2020 to hit up the Needles district to the south.
While within the Needles district we decided to take a hike on a rather rainy day at Cave Spring, which is a historic cowboy camp. The hike took us up and around the sandstone ledge seen here. The sandstone unit here is the Permian age Cedar Mesa Sandstone (~286 million years old), which is just slightly older than the formations seen above in the Island in the Sky district. The Cedar Mesa Sandstone is a near-shore sand dune deposit (the whiter, more resistant layers) which has frequent river and lake deposits (the redder, softer layers seen on the picture as the bottom layer).
The Cedar Mesa Sandstone is known to be a fantastic aquifer, and that is because water soaks up easily into the gaps between the sand in the sandstone. Many aquifers nationwide are actually within sandstones because of the porous nature of the rock. Here we have the actual Cave Spring, where the water that had soaked into the overlying sandstone is seeping out on top of a more water resistant layer below. And although we are in the desert with very little water nearby, this cave/alcove has abundant water and plant life just stemming from the cave walls. These caves were not only the location of a fairly recent cowboy camp, but also housed many Native American settlements throughout its history.
The trail took us up that overlying sandstone block within the Cedar Mesa Sandstone. The Cedar Mesa Sandstone is a rather thick unit, with many individual beds, as you can see here, looking between some of the small canyon walls towards the west.
A view on top of the Cedar Mesa Sandstone within this area looking towards the southwest.
Back down below the local cap of the Cedar Mesa, looking at the lower sandstone/siltstone beds that the spring was flowing along on top of. You can see the cross bedding of the overlying sandstone pretty well from this angle.
Further to the west is a road that nearly gets to the Confluence of the Colorado and Green Rivers. Here is a view from as close as you can drive, the Big Spring Canyon Overlook, looking towards the confluence towards the west. The Needles District is named for the features seen here which are throughout the district. These are vertical spires composed of the Cedar Mesa Sandstone, the same as at the Cave Spring above. The spires are formed from erosion along cracks, or joints, that naturally form a checkerboard pattern within the Cedar Mesa Formation. The cracks then consolidate the water, causing more erosion in these areas, further widening the cracks until only individual spires are left. The valley of the canyon here is the Elephant Canyon Formation, also Permian in age, formed from shallow coastal marine deposits.
References
https://www.gutenberg.org/files/51048/51048-h/51048-h.htm
https://pubs.usgs.gov/bul/1327/report.pdf
Visted several times since 2010
My first visit to Capitol Reef was back in 2010 for a geology field trip, for which I had made a geological tour website that is still a fantastic geological resource over at the U of U geology page. A few years after that I had found out that you could pick apples within the park and we planned our family visit for when we could pick the apples. Since then we had made an almost yearly journey down to Capitol Reef in mid fall for the apple picking.
Despite all these years of going to the park, I only just grabbed an entrance sign shot the last time we went in 2020.
The most characteristic features of Capitol Reef is the way that the rocks have been folded across the park. With an axis running nearly 100 miles north to south, is a feature called the Waterpocket Fold. There are several different types of folds when we look at rocks. When rocks are folded in a "U" shape, this is called an syncline. When rocks are folded the opposite way, essentially an "A" shape, this is called an anticline. However, when you have a stair-step fold, where one side of the fold is generally horizonal, then its comes down to another horizonal layer, you have what is called a monocline, and that is what the Waterpocket Fold is. You can essentially see this fold in the way that the rocks dip towards the east through much of the park, such as in the image above looking towards the south.
Cross section of the Waterpocket Fold by Ron Blakey. Image courtesy of the NPS.
Folded approximately 50 to 70 million years ago, the rocks within the park mainly range in age from the Early Permian age White Rim Sandstone (~280 million years old) to the Late Jurassic Age Morrison Formation (~150 million years old). Because of the Waterpocket Fold, the older rocks are easier to see in the western portion of the park and the younger rocks are more exposed in the eastern portion of the park.
Along the western part of the park is the Goosenecks Overlook, where you can look down into the oldest rocks at the park. The canyon was created by the Sulphur Creek cutting down into the rock units as the rocks were being uplifted. At the base of the canyon can be found the Early Permian White Sandstone. The White Rim is a ~280 million year old coastal sand dune deposit that had been bleached white by hydrocarbons flowing through the rock picking up the iron oxide within the sandstone. On top of the White Rim within the canyon here, and taking up most of the middle of it, is the Early Permian Kaibab Limestone, a ~270 million year old shallow marine shelf deposit that preserves the ancient Kaibab Sea that once flooded most of Utah.
On top of the Kaibab Limestone is the Lower Triassic age Moenkopi Formation (~245 million years old). The Moenkopi Formation is predominantly made up of the reddish-brown shale that is found throughout the western part of the park. This was deposited within an intertidal environment, with alternating sea levels producing thinly bedded layers of mud (shale) and sand (sandstone).
Due to the low water levels within the Moenkopi, it preserves many shoreline features such as ripple marks and...
...animal swimming traces. Here is where a small reptile was swimming along in fairly shallow water and its claws scraped the mud at the bottom. These features can be seen within the gully, just on the south side of the road near the Goosenecks Overlook.
On top of the Moenkopi is the Late Triassic Chinle Formation (~200 million years old). The Chinle Formation has a wide variety of rocks types including limestones, shales, sandstones, and conglomerates. Over the course that the Chinle was deposited the environment began shifting from a wetter environment dominated by streams, lakes, wetlands, and deltas, to a drier environment dominated by desert sand dunes. One of the most notable features of the Chinle is the presence of uranium, specifically within the yellow-grey river-deposited sandstone of the Shinarump Member of the Chinle Formation.
These uranium deposits were often mined in the early 1900's for medicinal uses and the 1950's for its nuclear properties. Eventually, the amount of uranium within the mines wasn't worth the cost of extracting it and the mines were abandoned.
On top of the Chinle Formation is the Wingate Sandstone. Like I mentioned, the primary reason that we headed to Capitol Reef was for the apple picking in the fall. The orchards are located mostly around the "town" of Fruita within the park. This is where the campground and the Visitor's Center are located. They can also be found extending east to west along the main highway, and the Fremont River, that cuts across the park. But from these you can get some gorgeous shots with the red rocks in the background. The rocks in the background are the Early Jurassic age Wingate Sandstone. The Wingate is a eolian sandstone, meaning that these rocks formed as part a desert ~200 million years ago.
Here is another orchard with the Wingate Sandstone in the background. The Wingate is characterized by those shear vertical cliffs and the red tint to the rock caused by the oxidation of iron coating the sand grains (rust).
One of the notable geologic features within the Wingate is Cassidy Arch, seen here just above the dead tree in the foreground.
Here is Cassidy Arch from the top, looking down into the arch.
On top of the Wingate is the Early Jurassic age Kayenta Formation (~190 million years old). The Kayenta is a mix of reddish-brown sandstones, siltstones, and conglomerates that interbed with each other. The Castle seen here on the left side of the photo from the Visitor's Center, is the vertically jointed Wingate Sandstone, while the Kayenta Formation is more horizontally jointed directly above it to the right.
Like the Navajo Sandstone above it, the sandstone layers within the Kayenta Formation are notable by the eolian formed cross beds, which are angular deposits created as sand dunes move across the desert. Wind blows the sand up one side of the dune, up over the crest of the dune, and then the sand falls down the slipface. The crossbeds are then the preserved record of the slipface side of the dunes locked into place by cement, often calcite or silica.
The Kayenta Formation also contains the Hickman Bridge, a natural bridge carved out of one of the sandstone layers within the formation by the stream flowing beneath it through the softer layers below.
View from underneath the bridge, hoping to get a good angle emphasizing the "bridge aspect of it.
View from the western side of the bridge.
Looking west off the Cohab Canyon Overlook you can see the dip of the beds towards the east as well as most of the rock units we talked about.
Turning around, here is the view to the east from the Cohab Canyon Overlook. On top of the Kayenta Formation is the Early Jurassic Navajo Sandstone (~180 million years old). The Navajo is a very thick (~1000 feet) eolian sandstone from an ancient sand sea known as an erg. The Navajo is notable by its whiter appearance than the reddish Wingate Sandstone and erodes more rounded features, unlike the Wingate which has more vertical jointing. The Navajo also has abundant cross beds throughout the formation.
The Navajo also has a type of weathering called honeycomb weathering, where these pockmarked patterns occur along the surface of the rock. This is produced as water wicks into the porous rock and dissolves the calcite cement holding the grains together.
Although the last major rock unit within the park, there are several rock units located above the Navajo Sandstone within the eastern parts of the main highway. These include rocks of the Jurassic age San Rafael Group and the Morrison Formation.
Looking west from the Hickman Bridge overlook.
References
https://sed.utah.edu/CapReef.htm
https://www.nps.gov/care/learn/nature/geology.htm
Visited in 2010 and 2014
Being only about three hours away from our house we have visted Dinosaur NM a few times. Here is one of the most recent trips.
Obligatory entrance sign.
"I hope that the Government for the benefit of science and the people, will uncover a large area, leave the bones and skeletons in relief and house them in. It would make one of the most astounding and instructive sights imaginable." - Earl Douglas, 1923
Earl Douglas discovered the quarry in 1909.
And here is the main attraction. The fossil wall in panorama form. The Fossil Wall is part of the Carnegie Quarry that was the original quarry from which the park was built around.
The northern end of the fossil wall. The Fossil Wall is in the Morrison Formation, a rock unit that is the Late Jurassic in age, approximately - 155-148 million years old. The Morrison Formation represents a large variety of environments, with mostly terrestrial rivers and lakes containing the most fossils. It is thought by scientists that the dinosaurs of Dinosaur National Monument accumulated within a local river, where the animals went to get water, but a drought cause all the water to dry up and the animals died. This was then followed by a return of the water, burying the animals in sediment and preserving them for all time.
And the southern end. Although dinosaur fossils are found in many different rock units, it is the Morrison Formation where most of the dinosaurs discovered in Dinosaur NM have been found.
View of the outside of the main exhibit building. The building is newly rebuilt (since the other one basically fell off the wall) and rests right on top of the fossil layer. The next picture is a shot in the opposite direction from the building.
Picture from the fossil wall in the northern direction (away from the building) where you can track the Morrison Formation fossil layer across the parking lot.
Closer up shot of the fossil layer from the previous picture. You can make out the Fossil Discovery Trail running along the base of the fossil layer towards the lower center of the picture (fossil layer is the dark layer just left of center).
View of the fossil layer looking back up at the building. Most of the best fossils were all up within the building but most people found it exciting to discover fossils "out in the wild".
Departing dino shot. The Stegosaurus represented here is one of the many fossils that have been found within the park along with Camarasaurus, Diplodocus, Apatosaurus, and Allosaurus, among others.
Here's a random geology picture that I came across on my phone from 2016. It is of Dinosaur National Monument from an airplane as I was flying over. From this angle you can really see the structure of the whole park with a great view of Split Mountain, the mountain in the middle of the photo.
Split Mountain is a geological structure known as a "plunging anticline". An anticline is when you fold the rocks into an "A" like shape (imagine bending a book with the outside edges bent downwards). Looking at the surface of the Earth with an anticline, the oldest rocks are in the center of the fold and the rocks progressively get younger in complimentary strips moving outward from the central fold axis. In the image below, C is older than B is older than A.
An anticline fold
If you were to think of an anticline fold as something like a jelly roll, then you tipped that whole thing into the the Earth, you would produce what is called a "Plunging Anticline". Here the youngest rocks go from oldest to youngest along the direction of the plunge.
A plunging anticline
Here D is the oldest on the surface with C, B, and A all progressively getting younger in the direction of the fold. (Same colors and letters as in the anticline photo.)
In Dinosaur National Monument, the plunging anticline is here running left to right (west to east) and is plunging towards the left (west). If we look at a geological map of the area, the ages of the rock units will be able to confirm that with. In this instance the oldest rocks should be on the right (eastern and upper) part of the plunge and the youngest rocks on the left (western and lower) part of the plunge.
Rock units outlined and labeled in Dinosaur National Monument
Although it is hard to tell, the labels have two parts. The first 1 or 2 letters stands for the age of the rock unit. Here is also a better geological map of Dinosaur National Monument.
- "M" = Mississippian
- "PP" = Pennsylvanian
- "P" = Permian
- "Tr" = Triassic
- "J" = Jurassic
- "K" = Cretaceous
The above order that I wrote them in is the order they appear in from right to left, and if you look at the geologic timescale below you can see that the Mississippian is the oldest in that list (~325 million years old (Ma)) to the Cretaceous, which is the youngest in the series that I listed (~66 Ma).
So, as I was saying, the aerial photo here is a great view of Split Mountain at Dinosaur National Monument, which also happens to be a plunging anticline.
Glen Canyon National Recreation Area
Visited in 2009
Glen Canyon National Recreation Area, also known more commonly as Lake Powell, is a rather large reservoir on the border of Utah and Arizona. It's a great place to go camping, but even a more fun place to take a boat and explore the canyon. Unfortunately this trip was long ago before I was collecting entrance signs, so no entrance sign shot for this one (yet).
Here is the view driving into the main canyon from the south. The geology within the Glen Canyon NRA is fantastic. There are rocks absolutely everywhere! The formation of the area occurred when the entire Colorado Plateau was forced vertically upwards. The reason for this is complicated and I won't go into it right here, but just know that this entire region is being pushed up vertically. Because the region is being pushed upwards, rivers in this region, specifically the Colorado River, are quickly eroding downwards into the ground, creating monumental canyons such as the Grand Canyon. Glen Canyon, upstream of the Grand Canyon, is also along the Colorado River. The Colorado River is dammed just across the Arizona border by the Glen Canyon Dam ,creating Lake Powell within Glen Canyon.
Glen Canyon NRA is so large that it covers a wide variety of rocks depending where within the canyon you are located. We camped near Bullfrog and stayed in this general vicinity for our entire trip so the rocks that we saw are all generally the same age and formation. Most of the rocks within the canyon are sandstones of various ages. The rocks above are rocks within the San Rafael Group, a late Jurassic (170 to 160 million year old) formation of rocks.
The rocks within Lake Powell sometimes form nice little islands that is possible to walk around. Here is one such island. All of the sandstone pictured here are likely the Entrada Sandstone, a member of the San Rafael Group. Although many of the sandstone units have a tendency to look alike. The Entrada is an aeolian sandstone, meaning that it formed from prehistoric sand dunes. The bed lines seen in the foreground are what is known as cross bedding, formed from the stacking of sand over a sand dune, creating parallel lines that often form at an angle to the way the rock unit (bed) is laying.
Within the Entrada sandstone I found these weird nodules as well. This is an iron oxide concretion within the sandstone. They likely contain goethite, as well as hematite where it is reddest according to sedimentologist Dr. Marjorie Chan of the University of Utah.
Some more iron oxide concretions within the sandstone. These are more common in the Navajo Formation, known colloquially as "Navajo berries". It is uncertain exactly how they form though.
Walking with the puppies along the slickrock surfaces of the Entrada Sandstone.
View into the distance of what is likely the Romana Sandstone, another Late Jurassic sandstone, which lies on top of the Entrada Sandstone.
Nice, puppy free, view of the Entrada Sandstone.
View across the water from the Entrada Sandstone island.
View of the lake from our campsite near Bullfrog.
References
http://www.npshistory.com/publications/glca/nrr-2016-1264.pdf
Golden Spike National Historic Site
Visited in 2008
Golden Spike is the second closest park to our home, but it is still a good few hours drive to get from our side of the Great Salt Lake to the northern side where the park sits.
A lovely entrance sign to greet us after a several hours drive.
The Golden Spike National Historic Site honors the location where the transcontinental railroad was completed, joining the railroad from the west, the Central Pacific Railroad, with the Union Pacific Railroad from the east. Pictured here are recreations of the trains that met at the Golden Spike ceremony, the Jupiter on the left and No. 119 on the right.
The geology here is slim but I'll do what I can. Seen here is a live demonstration recreating when the trains come together at the last tie for the Golden Spike Ceremony.
The crossing sign getting to the Visitor's Center. Golden Spike National Historic Site is located near the northern shore of the Great Salt Lake. The largest lake in the United States after the Great Lakes. The lake, and the park, sit within a portion of the United States known as the Basin and Range. This is an area where north-south running mountain ranges are spaced between north-south running valleys. The Basin and Range starts in mid-Utah at the Wasatch Mountains and runs west through all of Nevada to the Sierra Nevada mountains. These alternating mountain and valley lines were formed from what is called extension. The plate within this region is slowly expanding outward and the expansion of the plate is causing very large pieces of the plate within the region to rotate. The rotation tilts the large blocks, resulting with a corner of the block pointing up in the air. This corner becomes the mountain ranges in the region, while the area between these blocks is filled with sediment, forming the valley floors. It is in this region that the Great Salt Lake and the Golden Spike NHS sit.
Between where the two trains meet is a copy of the last tie that was laid down upon completion of the Transcontinental railroad. The tie itself was made of laurelwood. It was then laid down with four spikes; 2 made of gold, one of silver, and one a combination of silver and gold. The source of the spikes were from multiple places across the west. I had hoped I could figure out where the metal specifically came from but that is apparently an impossible task.
One of the golden spikes was from David Hewes, a San Francisco contractor who casted a spike from his own personal gold (possibly from California?). The next spike was a forged spike made out of silver from the Railroad Commissioner in Nevada. The 25 ounces of silver came from the Virginia City assayers E. Ruhling & Co (with the silver possibly from Nevada?). The mixed silver and gold spike came from Arizona, which was actually a plated iron spike with gold on the head and silver on the shaft. The final gold spike was a 9.5 oz spike made from $200 worth of gold that came from Frederick Marriott, a proprietor of the San Francisco New Letter newspaper company.
View of the plaque on the last tie that reads "The last tie laid on completion of the Pacific Railroad, May 1869".
Close up view of the trains surrounding the final tie.
References
https://www.nps.gov/gosp/learn/historyculture/four-special-spikes.htm
Visited in 2019
After leaving Arches NP, we hit up a small park on the border of Utah and Colorado, Hovenweep, which preserves several ancestral Puebloan buildings within a local canyon. The park has a nice short trail that leads around the canyon allowing you to get a 360 degree view of the canyon and all of the buildings located within it.
Entrance sign highlighting the high desert of the Colorado Plateau.
Hovenweep is represented by several buildings within this area that are estimated to have been built between 1230 and 1275 CE by the ancestral Puebloans. The name "Hovenweep" means "deserted valley" in the Ute/Paiute language and was given that by William Henry Jackson, a pioneer photographer who was here in 1874. Hovenweep itself is located on top of the Cajon Mesa, which is tilted towards the southwest. There are other districts and buildings of the Hovenweep National Monument across the border in Colorado, however they were not accessible at the time we were down there.
There are two rock units within the park. The primary rock unit is the Dakota Sandstone. This is the rock that forms the rim of canyon. The Dakota Sandstone is Early Cretaceous in age, ~100 million years old, and represents the western shore of the very large Cretaceous Interior Seaway. The Dakota is made up of yellow to grey sandstones, mudstones, and a few thin beds of coal. These were deposited within a wide range of coastal environments including deltas, alluvial fans, and coastal deposits.
Cross bedding is definitely visible within the Dakota Sandstone, indicating prehistoric sand dunes.
The Dakota Sandstone was so sturdy, that the ancestral Puebloans used it as the building stone for all of their buildings in Hovenweep. Below the Dakota Sandstone is the other rock unit within the park, the Burro Canyon Formation. The Burro Canyon is also early Cretaceous in age and is made up of conglomerates, shale, mudstones, and sandstones, all deposited within river and floodplain environments.
Here is part of the Hovenweep Castle, showing of the Dakota Sandstone building blocks.
Another part of the Hovenweep Castle from a different angle.
Here is a view down into the canyon, looking at the Square Tower. The Dakota Sandstone is a rather porous sandstone and therefore rain water has a tendency to soak up into it. The underlying Burro Canyon Formation, however, is impermeable and therefore the water will not go through the Burro Canyon and flows off the top of it. The result is a series of springs and seeps along the canyon walls next to the buildings, which is likely the reason that the ancestral Puebloans settled here in the first place.
View up the canyon from the far end of the trail loop.
View across the canyon of the Castle.
One of the other structures, Tower Point I believe.
Another view of the canyon from the end.
References
https://www.nps.gov/cany/learn/nature/dakota.htm
http://www.searchanddiscovery.com/documents/2007/07097serradji/
https://nmgs.nmt.edu/publications/guidebooks/downloads/25/25_p0239_p0249.pdf
https://www.nps.gov/hove/learn/nature/geologicformations.htm
Natural Bridges National Monument
Visited in 2020
A couple of hours drive south of Moab, UT brings us to one of the most remote parks in Utah and the second to last that we have yet to visit. Natural Bridges is a small park, with one loop road that brings you to the overlooks of three natural bridges and also has trails to each bridge. We ended up hiking the shortest trail down below the third arch and got some great photos in the process.
The entrance sign shot.
Each of the bridges is given a name in Hopi to honor the ancestral Puebloans who once lived here. The loop is a one-way drive so you can hit up each of the bridges in order. The first bridge is known as Sipapu bridge, which means "the place of emergence", an entryway by which the Hopi believe their ancestors came into this world.
Here is a zoomed out, panoramic view of Sipapu bridge from the overlook. The bridges occur within the Permian age Cedar Mesa Sandstone (~286 million years old), which is formed from near-shore sand dune deposits (the whiter, more resistant layers) and has frequent river and lake deposits (the redder, softer layers). This is the same formation that produces the needle formations within the Needle's District of Canyonlands National Park.
This region had been occupied off and on throughout the past several thousand years, with the ancestral Puebloans farming and building houses within the alcoves of the cliffs using the Cedar Mesa Sandstone as building stones. The houses were built between 1000 and 1270 CE, when eventually they left, likely due to environmental changes.
The second bridge on the loop is Kachina bridge, which is named for the rock art on the bridge that resembles the symbols commonly used on kachina dolls. Although "bridges", such as those seen here, and "arches", such as those seen at Arches National Park, are similar in structure they have different definitions. By definition, a "bridge" has water running underneath it, while an "arch" does not. However, they also form differently. While an arch forms from the slow dissolution of the cement within the sandstone and eventual erosion of the sand, a bridge is formed by river processes.
The three different bridges formed slightly differently, but all three of them have the same basic formation. This area is part of the Colorado Plateau, a region that has been slowly lifted upwards over time. As the ground surface is lifted up, the rivers cut down into the ground. This creates what is known as an entrenched meander, meaning a bend in the river that is firmly in place within the surrounding rock. Many rivers within the Colorado Plateau have formed these features including the Grand Canyon and Dead Horse State Park. Even though the meanders are entrenched, that doesn't mean they stop eroding the surrounding landscape. The rivers slowly cut through the outside of the meander by the forces of erosion and the increased water speed on the outside of the meander, eventually cutting off the old meander. This is the exact same process that goes on in all meandering river systems, like the Mississippi River, however since this river is entrenched, when it cuts off a meander it is doing so below a rock ledge, leaving behind a bridge of rock. Image from the NPS.
Here is a zoomed out view of the Kachina bridge, which is located on the right of the image. This view we are facing the outside of an entrenched meander, with the cut-off meander far in the background. The current river now flows in the entrenched meander at the front of the photo.
The final bridge, and the one we hiked to, is known as Owachomo bridge and means "rock mound", in regards to the mound of rock on top of the bridge seen on the left side of this photo.
View from below the Owachomo bridge. As long as water continues to flow under these bridges they will continually be eroded until they collapse. However, since this area is in the high desert, rain fall is relatively low and therefore the rivers are more like a trickle of streams at most times, preserving the bridges for many years to come.
Here is a view of some of the cross bedding within the Cedar Mesa Sandstone, which indicates that this particular part of the formation was once a sand dune. The cross beds are formed when sand is blown over the top of a dune crest and rolls down the opposite side. As it rolls down the leeward side, or slickface, the sand piles up in parallel layers that are at an angle to the ground surface, which is what is preserved as cross beds within the rock unit.
Here are more preserved cross beds in the Cedar Mesa Sandstone. As dunes shift directions, based on the wind direction, the cross beds change direction to match. This results in stacks of cross beds often going in different directions.
References
https://www.nps.gov/nabr/learn/historyculture/index.htm
https://irma.nps.gov/DataStore/DownloadFile/426441
Timpanogos Cave National Monument
Visited in 2008 and 2009
Timpanogos Cave is easily the closest National Park to our home, within an hours drive, and so was the first one we visited when we moved out here.
Entrance sign shot. There's not really an "Entrance Sign" like most other parks, just the wall in front of the main Visitor's Center.
Timpanogos Cave is located within the Wasatch Mountains. It is quite a hike to get up to the cave entrance from the visitor's center and most of it is uphill, although along a paved trail. When you get up high enough you actually have quite splendid views into the Provo Valley.
From the Visitor's Center, the trail climbs up over 1,000 feet and passes through several rock formations along the way.
Here is an artists rendering of the formations that you walk by, or through, along the trail up to the caves located within the Deseret Limestone. I will have to keep a better track of the specific formations that I photographed next time the I go. Image courtesy of the NPS.
Here is a man-made tunnel going through the rocks. Without a better picture, or returning to the park to verify, I'd say this is the Tintic Quartzite. This is based on coloration of the rocks and some other online sources. Limestone has a tendency to be slightly to very grey, while quartzite is often whiter. There is also a fault here, running right through the rock on the left side of the tunnel.
I'd say this is likely the same Tintic Quartzite with another man-made tunnel carved out of it. The quartzite formed from sand located at the edge of a shallow sea 540 million years ago at the start of the Cambrian. Over time that sand was cemented together to form a sandstone and eventually metamorphosed under heat and pressure, melting the sand grains together, forming the quartzite. River pebbles are often composed of quartzite because quartzite is a very, very strong and durable rock.
View over looking the American Fork Canyon, which is where the cave sits. Most of the rocks in the lower portion of the photo appear to be Tintic Quartzite, while you can see some of the grey limestones further up the canyon walls.
Another piece of the Tintic Quartzite along the trail.
The cave itself is located within the Deseret Limestone. The Deseret Limestone was initially deposited within a large sea 340 million years ago during the Mississippian Period, and is composed of the animals that used to live in that sea. During this time Utah was located much closer to the equator, allowing for warmer climate animals and formations to occur, such as carbonate deposits. Limestone is made up of mainly two minerals, calcite and dolomite. Calcite (CaCo3) is calcium carbonate, while dolomite (CaMg)CO3)2) is similar to calcite except that it has magnesium wedged into the structure. This actually makes it harder for dolomite to dissolve, but not impossible, as we can see here since the Deseret Limestone is composed primarily of dolomite. There are also some fossils located within the Deseret Limestone, like corals, however I didn't see any while I was there.
The way traditional limestone caves form, is from the slow dissolution of the limestone by groundwater or underwater streams. Groundwater is naturally slightly acidic from the mixture of carbon dioxide with the water, forming carbonic acid. This acid dissolves the calcite and dolomite very easily, especially compared to other minerals, and so as the water moves through the limestone some of it is slowly dissolved over time. Then as the water drips off upper parts of the newly formed cave, some of that dissolved calcite is left behind. This creates the cave formations that caves are so famous for. This type of rock is known as travertine, a type of limestone.
When the water is able to flow down the sides of the cave walls, or along large cave formations, this creates what is known as "flowstone" as seen here. All of these different cave formations are all created by the same minerals, just by differing processes.
Cave formations that hang from the ceiling are known as stalactites (hold "tight" to the ceiling) and the ones on the ground are known as stalagmites (might make it to the ceiling). When they connect, they are known as a column, as is seen here.
Here is a view of some stalactites flowing down from some flowstone further up. This type of formation is also sometimes known as "cave bacon" because of the crinkled and folded way that it forms makes it look like bacon.
Here are some of the more delicate cave formations in Timpanogos Cave, like soda straws and helictites, which are small spiral shaped formations.
Some more soda straws and helictites. The soda straws are the formations that look like, well, soda straws. They are the precursors to stalactites, which will eventually be built up into the traditional conical cave formation.
References
https://www.nps.gov/tica/learn/nature/geologicformations.htm
https://thelifeofyourtime.wordpress.com/2016/06/02/timpanogos-cave-national-monument/
Visited in 2009 and 2013
Obligatory entrance sign
View down the Lower Fork Virgin River from the bridge that leads to the Emerald Pools Trail. Most of the visible cliff rocks within the canyon are the Navajo Formation. The Navajo Formation is a rock unit that used to be a vast desert that crossed the middle of North America.
Nice view up the cliff along the Emerald Pools Trail.
The tired hiker on the trail.
Under one of the many waterfalls along the trail.
The Navajo Formation is actually prehistoric dunes. As the wind blows in a desert, the sand gets blown into piles called dunes. Eventually the sand gets blown over the top of the dunes. As more and more sand gets blown over the top, eventually the dune actually moves. The layers seen above, called cross-beds, are produced by this movement of the sand over the top and down the side of the dune. The side the sand slides down is called the slipface.
View out of the Emerald Pools Trail into the main valley. When sandstone gets lithified (turned into rock) it produces a really hard rock that is difficult to erode. So when a river does erode a sandstone, the rocks not directly next to the river can form steep cliff faces, as seen within the Zion Canyon.
Another view into the main valley.
View of the Three Kings.
Towards the eastern edge of the park is some of the best cross-bedding in the park.
Some more cross bedding.
Here are some pictures from the first visit to the park. This one is a view up the trail at the northern edge of the Canyon.
Some more cross bedding within the Navajo Formation.
You can see the erosion of the crossbedding produces a striking visual appearance.
Some more cross bedding.