Course:EOSC311/2026/Rock Formations: The Longest Historic Textbook

Group Members: Jessica Feeny, Micah Logan, and Riannon Wesley

Introduction

Overview

When starting an introduction to geological principles and events, it’s important to take a look at how they affect and shape humanity. Majority of rock formations were formed hundreds of millions of years before human existence so being able to connect these to what we're studying is an interesting way to go about understand things on a greater scale.

In this project, we will discuss rock formations such as Stawamus Chief in Squamish BC, Hoodoos in Kamloops,BC and Acasta Gneiss in the Northwest Territories. Alongside that, we will also discuss geochronology which helps us determine absolute ages of rocks, fossils and sediments

How Rock Formations Connect To Our Majors

Our respective majors are Anthropology, History and First Nations and Endangered Languages. We chose the topic of different rock formations as our project because of the vast history that rock formations have with connections to Indigenous land and storytelling throughout the earths timeline. Rock formations have helped decipher where settlements occur, or how different geological events have shaped migration, agriculture and infrastructure.

Why We Chose This Topic and a Statement of Connection

Many say that our history is found in textbooks, or in historical documents but what would you think if someone told you that the world itself is a giant library? It may not be comprehensible, but the earth itself can help us learn about the history that has happened over time. In doing so, we can look at the earths rock formations to help us clue into how it became what it is today.

We decided to chose this topic because it felt like a common ground that connects all of our majors to geology. The idea of history happening and forming around human history is an important lens into how it all pieces together.

Claim

With using rock formations and connecting it to our major, we can help understand how they influenced human history beyond their geological principles.

Rock Formations

By definition, a rock formation is a body of rock that is considered to be distinct enough and seperate from other surrounding rock layers . It would have to be recognizable by its appearance as well as its composition and large enough to show up on a geological map .

Some of these rock formations with consist of:

Stratum	A Single Rock Layer
Stratified Rocks	Rocks with Visible Layers
Unstratified Rocks	Rocks without Visible Layers

What Are Rock Layers?

To understand rock formations, we have to take a look at them under a geological lens, through that we can look at the different layers that make up rocks. These layers can help us to understand climate change in the area, geological events, past environments and also cultural history.

Stratotypes

Stratotypes are different reference rock layers that geologists use to compare the different geological formations. They're almost like a reference that can be used for identifying rock layers in other locations and can be a window into Earth's past by helping geologists to learn the climates, ecosystems and volcanic activity of the past.

Compressed Rock Layers

These layers are important because they can contain evidence of plant and animal evolution, ancient lake, forest or ocean environments and climate change . They also help geologists understand the human history and Indigenous use of the area .

In the United States, geologists started to catalogue different stratotypes in 2020 for their national parks and by 2023 they identified over 700 different stratotypes in 100 national parks .

Examples

In Mesa Verde National Park, the cliff house sandstone provided water through springs which influenced where Ancestral Puebloan people built their communities .

In New River Gorge National Park the rock layers contained coal which helped the regions mining economy .

In Yellowstone National Park, they recoded millions of years of volcanic activity in the area, the layers contained important fossils including the first dinosaur discovered in Yellowstone .

and finally, in the Grand Canyon National Park they discovered the largest collection of stratotypes in the USA. It showed a history of volcanic activity, erosion and how the landscape changed over time .

Ancient Preservation

Some Geologists use ancient rocks that have preserved chemical evidence of major events that happened in Earth's history. A specific example of this happening occurred in Mt. McRae Shale in Western Australia.

Geologists had found some evidence of oxygen in the Earths ocean before it ever reached the atmosphere, in this scenario it was before the Great Oxidation Event which was over 2.5 billion years ago. This geological event was discovered by geologists researching different chemicals in rocks which led to them discovering thallium and molybdenum isotopes preserved in these rocks.

This occurance is important because it helps us further our knowledge about when oxygen first appeared in the atmosphere and suggests that the oceans may have been full of oxygen before the atmosphere was .

Geochronology

With the use of Geochronology we can really determine who old a rock formation is and not just rock formations but also fossils and sediments. With the use of different tools to determine the precise age we can not only see where it is originally from but also be able to know what happened in that area as well one of these most powerful tools used in Geochronology is laser ablation which is used by making rocks in to smaller rocks for analysis. By using these tools we can read the worlds largest book collection which is the many rock layers that make up the earths surface.

Different Types of Rock Formations

Stawamus Chief in Squamish

Stawamus Chief South Peak

The Stawamus Chief is a granodiorite monolith located in Squamish, British Columbia and considered one of the largest in the world. It is a popular hiking location in BC and it is 700 meters above the Howe Sound. Due to its importance to the Squamish Nation, it holds a lot of important history behind it. One story associated with the Stawamus Chief is that it was a longhouse that was transformed into stone by Xáays who were four supernatural beings that came to the Squamish region, they say that the spirits trapped inside of the longhouse still appear in the rock, taking shape as animals or figures . The geological makeup of the Stawamus Chief is a granodiorite that was formed 100 million years ago in the Cetaceous period. There is some speculation that this could be apart of an extinct volcano . Much like other parts of this region, Stawamus Chief also was effected by glaciation, the cliffs were shaped by this glacial erosion during the last ice age. However, the glaciers had retreated over 10 thousand years ago and exposed the granite like surface we are able to see today .

Granodiorite

Granodiorite

Granodiorite is an "intrusive igneous rock” that is often light grey in colour but can sometimes appear white or pink. It has a mineral composition of plagioclase feldspar which is most abundantly in it, but it also contains quartz, potassium feldspar, biotite mica and hornblende . This type of igneous rock forms from magma that cools slowly in Earths crust. This helps support the claim that Stawamus Chief was once an extinct volcano. The cooling allowed for larger mineral crystals to grow. This type of rock is also commonly associated with mountain-building regions, such as the Squamish region. Granodiorite is probably one of the most common intrusive igneous rocks on Earth and is valued for its strength and appearance .

We can look at Stawamus Chief as a fascinating geological landmark, but also it’s a cultural landmark as well. Considering its age and how the granodiorite was shaped by glaciation, it’s connection to the Squamish Nation through storytelling and identity demonstrates how these types of landscapes can simultaneously hold important scientific information and cultural meaning.

Hoodoos in Kamloops,BC

Before we talk about Hoodoos in Kamloops, we should cover some details about what a Hoodoo is. A Hoodoo is a very tall rock, sometimes can be seen as mushroom like pillars. The formation of a Hoodoo starts with erosion over extremely long periods of time (thousands to millions of years), the softer base around the capstone (which is the top of the pillar) is taken away from wind, rain and water. Each base of a Hoodoo is made of dark marine shale, the pillar and capstone consist of sandstone. To give an idea of Hoodoos, when your at the beach making sandcastles try stacking multi-layers of nearby rocks and different types of sand (i.e. wet, dry, almost dry, very dry etc.). Once you form a pile of the layers dump water with a bucket near it so it washes some of the sand away, the formation result would be similar to a Hoodoo.

Some fun facts about Hoodoos: the name came from Southern Paiute word 'oo'doo' which translates to something that inspires fear. They are also in some Indigenous legends - example; "Bryce Canyon National Park were considered petrified remains of ancient beings who had been sanctioned for misbehavior". However, even if the spelling is similar the rock formations is not related to Hoodoo spirituality. Hoodoo is also known as "Tent Rock, Fairy Chimney and Earth Pyramid".

Hoodoos Example from Bryce Canyon

There is about 3 locations in Kamloops where you can view Hoodoos, 1 - The Cinnamon Ridge, 2 - East Shuswap Roads (Only a drive-by NO stopping as it's located on the lands of Tk’emlúps te Secwépemc), 3 - Dallas-Barnhartvale Nature Park. I will be focusing on The Cinnamon Ridge, but will include reference for the other two locations.

Cinnamon Ridge got it's name from volcanic rocks that have been weathered, the weathering produced iron and resulted as a cinnamon brown colour. Tourism Kamloops is a good hiking guide if wanting to view them in person, as it recommends the difficulty level and detailed terrain encounters during the hike. Another guide I found includes a map of the different geological locations you can find in Kamloops - Geo Tour Guide. As for the other two locations, East Shuswap is ONLY a drive-by in respect to the request by Secwépemc, and Dallas-Barnhartvale Nature has two options for great views of the Hoodoos. The guides provided include detail about the trails and safety precautions to take (as cinnamon ridge is very specific, if not followed precaution that it is illegal to hike over the train track).

Acasta Gneiss in the Northwest Territories

Outcrop of dark tonalitic gneisses near the discovery locality of the Acasta Gneiss Complex, Northwest Territories, Canada.

The Acasta Gneiss rock formation is located in the Northwest Territories in Canada roughly about 300km north of Yellowknife. It is roughly 4.0 to 4.03 billion years old and is known for being the oldest known intact crustal rock on earth. With this rock formation being one of the oldest on earth you would have to think what happened to over the years that it has existed. It is known that Acasta Gneiss is to be some sort of rare "time capsule." Which makes since with it being one of the oldest rock formations on the planet with this rock formation being one of the oldest rock formations on the planet it could hold a lot of history with in the rock formation.

Because the Acasta Gneiss is so old, Stern and Bleeker (1998) used a very precise dating technique called the SHRIMP which stands for Sensitive High Resolution Ion Microprobe. The way they used the SHRIMP was to measure uranium lead isotopes in the zircons to better determine the age. These zircon crystals showed that the original igneous rock was crystallized 4.03 billion years ago

Conclusion

Evaluation of the Connections

Although each geologic location is different, each connect through stories and the historical significance rocks hold. They also mention the dating period of the rocks and discovery of the age, including the tools used to determine the relative or precise age of each rock. From weathering processes to preserving lead and granodiorite millions or billions of years ago, each are connected to one another to make up earth. We may take advantage of the usual rock we see day-to-day, like gravel in a park or tumbled crystals in a shop, but behind both hold stories that will outlive everything. They may even preserve us as time goes by, which we know to be similar to the discovery of dinosaur bones. Another important factor is how the connections impact each other, and are very closely intertwined although seemingly slightly different from one another. Without glaciers we wouldn't have sculpted landscapes, without igneous rocks we wouldn't have the dating methods, and without geochronology we wouldn't know about possible fossils, sediments or age of the rocks.

References

This Earth Science resource was created by Course:EOSC311.