Grand Canyon vs. New River Gorge. James Kang. Quantitative Methods in Rocks and Minerals. Steve Teeter

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1 Grand Canyon vs. New River Gorge James Kang Quantitative Methods in Rocks and Minerals Steve Teeter July 16 th, 2010

2 GC vs. NRG 1 Abstract The Grand Canyon and New River Gorge are similar landscapes located on the opposite side of United States, yet has completely different environment. Grand Canyon, 277 miles long with width up to 18 miles and depth up to 1.2 miles, covers Utah, Colorado, New Mexico, and Arizona. New River Gorge is 320 miles long flowing through the Appalachians across North Carolina, Virginia, and West Virginia. Both places were formed in a similar way about 20 millions of years ago. These two landscapes are very similar in geomorphology, and geography but has completely opposite climate and therefore ecology.

3 GC vs. NRG 2 Similar, but different at the same time, the Grand Canyon and the New River Gorge are paradoxical sights located almost at the opposite ends of the continent. The Grand Canyon is 277 miles long, 15 miles wide, and 1.2 miles deep at its maximum covering Utah, New Mexico, Arizona, and Colorado. It is one of the major sight in the world with over five million people visiting each year. On the opposite side of the continent, the New River flows through North Carolina, Virginia, and West Virginia. The name for this river is very inaccurate because the New River is one of the world s oldest rivers. It is about 320 miles long with many tourist enjoying the river for recreational sports. The Grand Canyon and the New River Gorge have many differences, but also have a major similarity. They are very similar in their geomorphology, but different in their geology and climate. Being one of the oldest river on Earth, the New River was created before the Grand Canyon, but in a similar ways. First of all, the Grand Canyon was a flat plain about 10 millions of years ago. However, due the uplift where one part of the land rises while the other part stays down, the tributaries feeding into the Colorado River met and formed a river through the gorge (Hamblin 34). By the process of uplifting, two things happened, mass wasting and stream erosion. Mass wasting is the movement of land materials down a slope due to gravity, and then these materials are carried away by the river, eroding away the gorge. Stream erosion happens when the water containing sediments flows through the river (Hamblin 35). As the water flows it picks up the sediment of the surface. Therefore, the combination of mass wasting and stream erosion over millions of years created the Grand Canyon which is still eroding away today. The New River Gorge is a similar land structure as Grand Canyon but was created long before than the Grand Canyon. Very similar to the geomorphology of the Grand Canyon, the New River Gorge was formed mainly by a process called entrenched meandering. This process

4 GC vs. NRG 3 has the same effect as the stream erosion except it shapes the river itself. Entrenched meandering is when the river erodes away the surface material and deepens the meander and the river as it flows downward (Kaymoor 10). This process is why the New River has wavier characteristic than the Grand Canyon. The earliest Grand Canyon rock record dates back to the Precambrian era. This rock is the oldest layer of the Grand Canyon and is part of a complex group of igneous and metamorphic rocks called the Granite Gorge Metamorphic Suite. This rock is located mostly at the inner gorge and it dates back up to 1.84 billion years. This type of rock was originally on the seafloor, but due to uplifting, it is now located on the bottom of the canyon.the next layer is mainly from the Paleozoic age anywhere from 250 million to 550 million years old (Houk 23). The Grand Canyon is the best sight in the world where the rocks from the Paleozoic era are clearly exposed and distinguished from the layers above and below. The rocks from this era include sandstones, hardened mud and some limestone. As the period reached the end of Paleozoic era, the water was limited so much of the rock from this era were land deposits including accumulated river mud and sandstones. Because of its dryness, as the wind blew, the sandstone particles accumulated up to 4 or 5000 feet of sandstones near the Grand Canyon (Houk 35). However, most of the rocks from this era are now located few miles south of Grand Canyon due to uplifting and erosion. Although the rock layers are very important to the Grand Canyon s geology, one of the most important features of the Grand Canyon is the Colorado River which has a major role in creating the Grand Canyon. This river stretches for more than 1400 miles from the Rocky Mountain of Colorado to the Gulf of California. Its main water resource is from the annual snow melt down from the mountain. However, the water level is slowly declining from the declining climate of the Grand Canyon area. The river is responsible for the canyon s existence as it carves

5 GC vs. NRG 4 and shapes the canyon with its erosive power even today. On the other hand, New River Gorge is one of the oldest rivers on Earth anywhere from 10 million to 360 million years old. This river s location is very unique because it is the only river that flows westward across the Blue Ridge and the Appalachian. In shaping the natural landscapes, climate has the most effective role as shown in both Grand Canyon and New River. Although the formation of the two landscapes are similar, their environments are completely opposite. First of all the Grand Canyon is located near the western desert area where the temperature difference of the day and night is extremely high. Therefore, there are limited species of plants that can survive in the Grand Canyon. Overall, the average precipitation in the Grand Canyon is about 11 inch per year and during the summer, the temperature can exceeds 110 degrees (Thornbury 275). The Grand Canyon is divided into different region, South, North, West, and Central. Usually, the temperature in the central part is the highest with lesser precipitation, but the northern part has the most precipitation with cooler temperature of 80s in the summer. In this harsh climate, only small plants like the cactus which can save up water can survive (Price 28). Because there is no moistures deep underground, plant s roots only remain near the ground level making erosion lot easier from unstable ground. Given these conditions, the only animals that are common in the area are some reptiles. Opposite of the Grand Canyon s climate, the New River Gorge has a relatively warm and mild climate where numerous types of vegetation can flourish. The climate of the New River is humid and has an average precipitation of 45 inches per year and 30 inches of snow fall. With this mild climate the plants have their roots settled into the ground, making the erosion process slower. New River has plenty of water so plants that both require lots of water and little water can settle. Also, the combination of native and introduced species exist in the river gorge because

6 GC vs. NRG 5 it acts as the migrating corridor for plants since it s the only river flowing from southeast to northwest across the Appalachian (Kaymoor 15). Not only plants, but many species of bird travel through this area between September and January each year. Some of the different kinds of common trees are red and white oak, red maple, and eastern hemlock. Also, different types of animals including deer, squirrel, rabbit, and other forest animals live in the area. Overall, the history of the Grand Canyon and the New River Gorge may be similar, but as time passed the two landscapes have completely changed. Grand Canyon and New River Gorge have similar geomorphology, but they have their own distinct geology and climate. Many Geologists questions and predict the future fate of the Grand Canyon and New River Gorge, will they continue to erode away and someday disappear?

7 GC vs. NRG 6 Work Cited Hamblin, W. K. (2007). Anatomy of the Grand Canyon. Grand Canyon: Grand Canyon Association. Houk, R. (1996). An Introduction To Grand Canyon Ecology. Grand Canyon: Grand Canyon Association. Kaymoor. (1992). development concept plan. New River Gorge, Price, L. G. (1999). An Introduction To Grand Canyon Geology. Grand Canyon: Grand Canyon Association. Thornbury, W. D. (1965). Regional Geomorphology of the United States. New York: John Wiley & Sons, Inc. ACE Adventure Center, (2005). New River Gorge National River. Retrieved July 16, 2008, from: