13 minute read

Geology

Geologic History of North Carolina

In order to understand the scientific data that we collected and what it means, we must first look at North Carolina’s geological history and how geological changes began. Geological changes in North Carolina began around 1,700 million years ago thanks to the uplifting of tectonic plates. This process created mountain ranges and made North Carolina what it is today. Once these mountain ranges were created, erosion came into play and over time eroded numerous mountains and produced new shapes out of them. Thanks to different tectonic plates moving and colliding with each other, islands and vast landscapes were moved, including what would become North Carolina. Eventually, after millions of years of moving around, North Carolina found its current place on the eastern coast of North America, sometime before 200 CE. The reason that North Carolina and its provinces are so popular in the present day is because of these geological processes. (Walbert, 2018)

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Since all of these changes, many famous geologists, like James Hutton, Charles Darwin, Charles Lyell, and William Smith have studied geology and contributed to the Body of Knowledge. All of these contributions have made geology the science that it is today.

An extremely well-known geologist, who is considered by many to be the father of modernday geology is named James Hutton. Around 1750, he started studying and observing how the land around him interacted with the wind and water due to erosion. He revolutionized many theories now widely accepted, such as uniformitarianism. This is a geological theory that states how the changes in the Earth’s crust have resulted from a uniform continuous process over time. This process turned out to be the moving of the tectonic plates. (Rosenberg, 2018) He also put to rest the universally accepted idea that the Earth was only a few thousand years old. Another notable geologist is Charles Lyell. He had groundbreaking theories regarding how old the Earth was and published several famous books explaining his ideas of how old the Earth was. His findings proved it to be around 4.5 billion years old. All of his ideas about how the Earth was formed and how old it truly is are now universally accepted and truly changed how we think about the Earth and why we think it is as old as it is. He also contributed and added to Charles Darwin’s theory of evolution. (Mitchell, 2019)

This is how North Carolina underwent many changes over the course of millions of years and how famous geologists made groundbreaking discoveries to help further explain its history. If not for them, North Carolina’s background would still be a mystery. Around 1750, he started studying and observing how the land around him interacted with the wind and water due to erosion.

Works Cited: https://www.thoughtco.com/most-influential-geologists-4039942 https://docs.google.com/document/d/1REId8LS55NPhFb287LSnWk9RrihcV0GZZy3Oh7OFvE/edit https://www.thoughtco.com/what-is-uniformitarianism-1435364

Geological Methods

When we gathered data, we started by taking the soil samples. First, we collected the samples on land. This was achieved by pushing the core sampler down halfway. When we got the sample, we took some to the soil chemists and kept the other portion for our research. We grabbed a piece and used the colors on the Munsell scale, the system used to tell the color of the soil. After identifying the color, we determined the minerals which include: calcium, low oxygen, organic matter, iron sulfide, and iron oxide. Next, we took a small piece of soil, that should fit in the palm of a hand, and extracted all of the small rocks and twigs. We poured clean water onto the soil and rolled it into a ball. We did that for about a minute before beginning the next step of turning it into a ribbon. To do this, we pinched the edges as far as they would go without breaking, then measured it. The length of the ribbon determined the texture of the soil. The texture ranges from sand to clay loam (which is a combination of silt, sand, and clay), to heavy clay. Note: if the soil is made primarily sand particles it may be challenging to collect it in the core sampler. In this case, it is important to be extra careful when extracting it. That process is then repeated with all of the samples.

Next, we found two rock samples. With rocks, we tested for: color, luster, type, hardness, and streak color. We started with the color and luster since it can be observed by looking at them. After that, we found the streak color by pulling out the Altoid tin that is full of white and black tiles. We scratched the rock against both, and whatever color it left behind was the streak color. Then, we figured out the rock type. If the rock was not clearly sedimentary, metamorphic, or igneous, then we cracked it open. We always wore safety goggles and gloves. Lastly, we determined the hardness of the rock by taking out the small paper with the chart indicating the different levels of hardness. We typically started in the middle of the hardness scale, which is glass. If it scratched the rock, then the hardness was less than what

it was scratched with, but if it did not scratch it then the rock is harder. We kept scratching the rock until the hardness was narrowed down.

During each site study, we used the core sampler, the tiles in the Altoid tin, laminated sheets, and a pocket microscope. When breaking rocks, gloves, glasses, and a rock hammer was required. The core sampler is a metal tube piece of equipment used to collect the soil. We pushed and twisted it into the ground until it was halfway, then carefully pulled it out. The Altoid tin includes the black and white tiles on which testing of the streak color occurs. The laminated sheets have the colors, minerals, and textures written out for when we are testing. The microscope is used to identify the luster of the rocks. The gloves, hammer, and safety goggles all fall into the same category because when one is used, so are the others. We strike the rock with the pointy end of the hammer and if the rock won’t break, we turn it over and strike with the flat end. This process sometimes took a while depending on the hardness and size of the rock. These are our methods and ways of gathering data. With these methods, good, valuable and informative data can be collected and contributed to the B.O.K.

Geological Data

Black Balsam Knob: For texture, the soil was heavy clay, the color was 5YR 2/4. The minerals in all of the samples were calcium. The second sample’s texture was light clay, and the color was 10YR 4/2. In the third sample, the soil texture was sandy clay loam and the color was 5YR 2/2. The first rock was a whitish orange and it had a shiny luster. Luster is the shiny bits on the rock, called mica. The streak color was white. The hardness was nine. The rock type was metamorphic. The second rock we found was pure white, had some luster, and had a streak color of white, the rock was sedimentary.

Graveyard Fields: The first soil sample at Graveyard Fields was heavy clay. The color was 10YR 8/8 and 10YR 2/2. The minerals in the soil were rich with calcium. The second soil sample was sandy clay, and the color was N2. This sample was also rich in calcium. The last soil sample was in the water and it was only sand. The color was 10YR 4/4. Our first rock sample was sedimentary, the color was white and orange, and the luster was semi-shiny. The hardness of the rock was three. The second rock sample was orange, brown and white, the luster was shiny, and the rock was sedimentary. They both had a white streak color.

Fontana Lake: The first soil sample’s texture was clay loam, the color was 10YR 6/9, and it contained calcium minerals. The second sample had the same minerals, but its color was 10YR 4/4 and its texture was light-medium clay. The third soil sample’s texture was light clay, the color was 5YR 2/6, and it also contained calcium minerals. Both rocks we collected

were metamorphic. The first had a silver, white and orangey color, it had no luster, its streak color was white, and it had a hardness of nine. The second rock sample was similar to the first, but consisted of two different colors; silver and grey. It had no luster and had a hardness of eight.

Goose Creek State Park: Soil sample one had a sandy texture, the color was N4, and it had low oxygen. For the second soil sample, the texture was sandy clay, the colors were N2 and 5YR 4/4, and the minerals were calcium. For the third, the texture was sand, the color was 10YR 8/4, and the minerals consisted of organic matter. This time, we found three rocks instead of two. For the first rock sample, the colors were grey and black, the luster was semi-shiny, the rock type was sedimentary, and the hardness was seven. The second rock was white and black, there was no luster, the rock type was metamorphic, and the hardness was one. For the third rock sample, the colors were brown, white and grey, the luster was semi-shiny, the rock type was metamorphic, and the hardness was five. All of the rocks had a white streak color.

Fort Macon: Our first soil sample was sand and the color was 10YR 8/4. It had a lot of organic matter in it. The second sample was also sand but the color was 10YR 6/2. The sample was also rich in organic matter. The third sample was also sand, the color was 10YR 4/2. The sand had low oxygen. The rock sample had a hardness of three and had no luster. The color was a mixture of grey and brown and the rock was metamorphic. The second rock was greyish black. The rock type was metamorphic and there was no luster and the streak color was white.

Geological Conclusions

While our data can stand alone as its own science, it doesn’t have to, meaning it can have connections with other sciences. Our data is connected to several other science groups including the meteorologist and the botanists. Our science job is connected to the meteorologist because the different rocks that we find are usually very weathered down and because of this, we can ask the meteorologist exactly what this means and how weathered it is. This is a great connection to have because it means that we can find out even more about our rock samples than we can determine alone. Another science job that we are connected to is the botanists because we study different soil types and the type of plants that can grow in a particular environment is dependent on the type of soil. This makes our jobs intertwined and dependent on one another. This is also a great connection because it gives us another group of people to communicate with and it lets us have a second set of eyes on our data. These are two of the other science jobs that we are connected to.

We collected this data and scientific findings because we knew it would have good value, significance, and would contribute to the B.O.K. We have compiled all of our data and drawn the following conclusions: in all of the site studies closer to the coast, the soil was sandier and the rocks were more brittle. However, farther away from the coast, the soil contained more clay and the rocks were considerably harder. Most of the soil in both Missouri and North Carolina was rich in calcium, meaning they were shades of brown, from 10YR 4/2 to 5YR 2/2. The soil samples collected from the water at all of our site studies were low oxygen, which is indicated by greyish color and can go from 10YR 6/2 to 10YR 4/2. However, farther away from the coast, the soil contained more clay and the rocks were considerably harder. Based on these findings, we can conclude that geologic features change according to the environment that they are exposed to. The soil closer to the coast is generally sandier because of erosion and not just erosion from the sea. Because water naturally flows into the ocean, the water found in the sea could be from hundreds of miles away. As water travels from the continental divide, it erodes rocks that can consist of more sediment by the time it reaches the coast. That is why there are fewer rocks near the coast, as opposed to farther away from it. As for the differences in soil texture, the explanation is remarkably similar. As the water deposited sand onto the land by the coast, the soil became less pure and acquired more sand. From this, we can conclude that the farther away from the coast the soil is, the more clay it has and the more solid the rocks are.

Advice For Future Geologists

Being a Geologist requires clear, concise notes that are legible and easy to understand. This means clearly labeling data tables and writing neatly. While collecting samples, avoid choosing areas in which the soil is similar. Try to select areas where there is a noticeable difference in vegetation, soil color, moisture, and texture. This assures that the data collected is more diverse. Investigating why the soil changes at various locations is something that should be thought about during Field Ecology and what the data means. For example, what does it suggest when the soil has heavy clay or has calcium minerals in it? Taking the time to comprehend the data is a large part of the job and is something that should be focused on. One piece of advice we have to all future Geologists is to label which soil sample is the one in the water. Even though we always did the soil sample in the water last, it would have been better if it were labeled so someone reading the journals could understand what they were looking at. Another suggestion is to bring colored pencils along to draw the soil samples. There is only so much information that can be inferred from graphs and tables, as it is just numbers. Drawing the soil allows for easier comprehension of the data.

After all of the soil samples are collected and recorded, it’s time to move on to the two required rock samples. It is recommended that they are very different rocks and aren’t rocks from the same spot that look similar. Sometimes when a rock sample is collected, the type of rock may be clear without breaking it open. It is tempting to not have to break it open, but it is highly recommended that it is to confirm the suspicion. While it is only required to analyze two rock samples, sometimes, when in a diverse ecosystem, it can be beneficial to collect a third, or even a fourth so that there is more data. Regardless of how many rocks are collected, the tests must be run carefully to get accurate data. It is also recommended that for both soil and rocks to not merely collect quantitative data, but also qualitative data, simply because qualitative data has much more meaning and isn’t just graphs with numbers. As a Geologist, the job can be challenging, but if this advice is followed, success will be assured.