Essay on the Rocky Mountains: Structural Geology and Formation Process

The Rocky Mountains is an extensive mountain range located in western North America. It stretches for 1,900 miles from British Columbia to New Mexico in the southwest side of the United States. The age of the mountain is estimated to be 55 to 80 million years old when tectonic activities and erosion caused plates to slide underneath the North American plate (Bird, 1503). This resulted in dramatic formation of valleys and peaks as the glaciers erupted. The highest peak of the ranges is at Mount Elbert in Colorado with a height of 14,440 feet above sea level. Some of the western edges in the Rocky Mountains includes ranges such as Wasatch, Bitterroots, and Sawtooths.

This paper seeks to understand the structural geology and the process of formation of the Rocky Mountains using previous studies and discoveries available. Obtaining the structural formation process is challenging, but different literature resources offer clear insights into the topic. Tectonic evolution of the earth is characterized by movement of tectonic plates and rocks. As a result, it distorted the general shape of the grounds to form extensive ranges. When researching on geological data about the Rocky Mountains, the sources of the tectonic forces and the formation of the crustal structure fascinated me. The geographical differences between before formation and the after requiring adequate geological data to explain.

Different literature sources have explained theories on the origin of the Rocky Mountains. However, despite being able to explain some of these theories, it is not clear on the origin of the tectonic forces, what caused them, and their full impact on the land beneath except the visible one. In investigating this formation, the types of rocks, and their generation is important to explain the possibilities of different reactions and fusions that took place. Some of the mountains essential to this study include the Dogtooth Mountains, the Sawtooth Mountains, the Matterhorn Mountains, the Complex Mountains, and the Synclinal Mountains (Roy, 978). Therefore, literature related to these formations is relevant to this study.

Observation and Interpretation

From the Cooperative Institute for Research in Environmental Sciences, Jones & Palmer, discovered brought some new insights to the formation of these mountains. Usually, the formation of the Rocky Mountains fascinated most scientists despite them being able to explain the origin of the Himalayan Mountains. It appears like a mystery whereby scientists cannot tell the root cause of these happenings. In the previous observations, they believed that the oceanic plates were moving under, and the North American plate rose and rubbed with the bottom of the continent to Colorado from the ocean. However, this study suggests the removal of materials that rugged underneath and caused a pile-up of materials in California and Arizona. This was unsatisfying as far as research and factual findings are concerned.

Formation of Rocks

In a new explanation, a new model explaining the existence of a thick lithosphere on the stiff part of the continent’s bottom. There was a protrusion of a fluid mantle flowing underneath into the Colorado Basin, which was a hole formed after forces amplified the Pierre Shale peaks on the central parts of the Rocky Mountains. The fluid mantle was caused by eruptions and melting of tectonic plates that gave them new shapes (Gutscher, 819). As a result, they would depend on the new forces to be molded into definite shapes at they pleased. A hypothesis from a study put forward in the ’90s, a collection of processes was chosen to explain the mountain belts and their movements. Perhaps the belts are still adjusting their positions whenever pressure piles up beneath. Jones believed that when pressure at the bottom increases, the heat goes up, which increases the likelihood of the plates melting and sliding over each other.

In 1915, a German meteorologist, Alfred Wegener, investigated the origin of continents and oceans. He discovered that whenever two points of plates were joined, their rock structure and fossil record would be similar as the joiner spread the components of each material into the other (Thompson and Mary, 164). Perhaps the rocked formed would be of different composition but often will have same properties. The greatest breakthrough for scientists came in 1950’s when scientists sought to understand the floor of the ocean. With sophisticated eco-sounding equipment, they would understand the terrain of the ocean floor and how it is connected to the dry land mountains. In one of the discoveries, there was a valley at the top ridge.

From a study by (Bird, 3977), the Rocky Mountains consist of ancestral rocks that were formed before the mountains were formed. Some of these rocks are the oldest in the history of rocks in the North American continent formed about 1.7 billion years ago. In the southern part of the mountains exists the Pennsylvanian ancestral rocks, which disturbed the mountain building process as they shot over the earth surface when they were subjected to pressure. In the Mesozoic deposition of rocks in the Rocky Mountains, a mix of marine, continental, and transitional environments contributed to the change of the sea level. About 4500 meters of sediments accumulated on the floor of the ocean thus driving the sea to cover the exposed on the coastal line (Bunge, Han, and Stephen, 337). Therefore, submerged land surface would also contribute to the pressure build-up to affect the formation of the mountain ranges.

Raising of the Rockies

The appearance and outlook of the Rocky Mountains insinuate a rug spread between shields of Canadian ancestral rocks. The Kula plate, which holds the hardwood floor of the Canadian ocean plate may have pushed the rug towards the continental plate and thus forming uneven wrinkles on the land, which are the mountains. However, this may have been evident only near the coastline as it explains the meeting point between the oceanic and continental plates. However, it does not explain the spread and extension of the mountains further inland (Cross & Pilger, 874). In their endeavors, different scientists tried to come up with explanations.

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In the subduction process, it is crucial to understand that continental plates are built as a belt, which can stretch from one seafloor to the other side of the continental coastline. This means that when subjected to pressure, the belt can adjust itself as it seeks balance on its rocks. A similar relation to this is during earthquakes. Often, when a tremor takes place at one region, it sends signals to other regions within the same belt such that the tremors can be felt though not in the same magnitude. In the Rockies, the pressure built at the joiner of the oceanic and continental plates might have built stress on the belt of the continental plate, which extends in-land (Dickinson et al., 2). As the continental belt sought to find its balance, the rocks were moved according to their weights and composition, thus forming the mountain peaks and valleys.

Looking at the current landscape, scientists believe that the Rockies might have undergone extreme erosions over the years. This activity stripped the high plateau to expose the ancestral rocks beneath. Some of these rocks are hard volcanic rocks that form part of the rocks that hold glaciers during the cold seasons. The Colorado sedimentary rocks are characterized by long-term erosion and glaciation activities (Livaccari, Richard and Frank, 721). The sandstones that formed most parts of the rocks on the valleys is also an illustration of these activities. Therefore, perhaps the mountains were high and at the same height in terms of different peaks. However, because of erosion and glaciation processes, some mountains were eroded faster than other ones thus forming different peaks and varying sharpness.

Also, due to the gradually changing climate, the existence of ice in the region is being threatened. Whenever a massive melting of the ice takes place, many rocks from the mountains are dragged down-hill and covers the bottom of the mountain valleys. This means that the composition of rocks at the bottom keep changing (Bird, 751). Therefore, whenever the valleys are subjected to pressure, the rocks can mold themselves into different shapes. This explains the lack of rugged terrains on the bottom of the Rocky Mountains. These processes perhaps took place close to 1.8 million years ago. Besides, scientists relate have related volcanic activities to the formation of these mountains. Evaluating the composition of the rocks both at the peak and valleys on Rocky Mountains, Jones discovered that most of the rocks were volcanic. This means that there is a possibility that volcanic eruptions took place in the region.

Discussion

From this study, different theories, ideologies, and structural brainstorming take place. For instance, one theory explains the sliding of the tectonic plates, that is, the continental plates sliding over the oceanic plates, building up pressure and forming the inconsistent mountain variations. According to the scientists, the inconsistent mountain formation may have been triggered by pressure beneath different types of rocks (Jones, Leslie & Sonder, 640), and Jeffrey. In another theory, the Rocky Mountains were formed when the oceanic plate collided with the continental plates during the movements of the tectonic plates. After meeting and colliding, they formed wrinkles, which are now the Rocky Mountains. The third theory suggests eruption of volcanoes on the west side of Colorado (Wolf and John, 98). The structure of the mountains especially at the peaks shows the occurrence of a volcanic eruption.

In one theory, the collision between continental and oceanic plates demonstrates the extent to which ancestral rocks were subjected to pressure. The irregular bounded peninsula was formed around the transcontinental arch and was pushed inwards for form a bulge upwards, which became the mountains. Collisions of continental and ocean plates have contributed to formation of most coastal mountains over the years. Different shapes of mountains took the shape that the magnitude of their pressures subjected them to become. Therefore, the formation of Rocky Mountains took place due to collision of tectonic plates and forming wrinkles, that were a long stretch of m

In the second theory, the Rocky Mountains may have been formed as a result of the continental plate sliding over the oceanic plates. Then when the plates were moving, there were plates collided, where they built up pressure, which resulted in melting of both plates at the point of collision. As a result, the continental plate slide over the oceanic plate, which resulted in building up stress among the continental rocks. In the process of stabilizing this stress, the Rocky Mountains were formed as the earth bulged from the outside (Riter and Smith, 268). Therefore, this formation was as a result of continental rocks stress.

In the third theory, the Rocky Mountains were formed as a result of volcanic eruptions. Scientists still believe there is a possibility that these mountains were formed from volcanic eruptions. As the earth exploded from beneath, a stream of lava came out and rolled down across the flat area along the coast and inland (Humphreys, 576). As a result, it formed rolling plains of hills and valleys, some which were higher depending on the material deposits and some that were lower. Over the years, the hills experienced extreme erosions and glaciations processes thus resulting in distorted shapes of the rocks. Usually, the rocks eroded rocks were being deposited on the valleys while others were washed away to the ocean. Through this process, the sharp peaks and flat and some trenched valleys were formed.

The spread of these mountains is what fascinates scientists the most especially due to their length and cratonic deformation that they display. Cratonic deformation was concentrated at the center of the mountains and its intensity reduced as you move the spread (Erslev, 74) outwards. The ancestral Rocky Mountains on the New Mexico and West Texas sides displayed progressive collisions of North America and South America-Africa plates.

Conclusion

Therefore, the formation of the Rocky Mountains took place close to 1.8 million years ago and started before the ancestral rocks were formed. As scientists endeavor to discover, they juggle through identifying and explaining the different processes that the areas could have undergone in the formation of the mountains. They touch on movement and collision of the tectonic plates, collision and sliding over each other, and finally occurrence of volcanic eruptions that shaped the earth surface after the lava dried up to form the parent rock materials. Although these theories are yet to be proven, having a structural difference in the formation aid the conversation on the topic. With continuous reading and studying formation of rocks and mountains, it may provide some clear insights to explain the origin of rocks, their true composition, and thus become convenient in explaining the formation of mountains.

Works Cited

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