Patton, Means and Caffey-Dixon
From GeoClasses
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LOOKOUT MOUNTAIN'S RUBY FALLS
Abstract
The information provided will cover the formation of Lookout Mountain’s Ruby Falls located in the eastern part of Tennessee. We will emphasize on the principle of plate tectonics and how it has affected this particular landform in Chattanooga Tennessee. The formation of this landform will also provide information on the different minerals and weathering processes. You will also find information regarding what type of sedimentary rock Ruby Falls is composed of and how these compositions created other sediment formations, such as the cave and water fall that exists to this day.
Introduction
For many years the formation of land has changed from the converging and the diverging of continental plates. Within these changes, seas, lakes, rivers, mountains, and islands have surfaced. Mountains have appeared on some parts of the continents. In North America, many chains of mountains have formed by the convergence of continental plates. When continental plates collide together, the crust tends to push upward and form mountains. Mountains can be very interesting to learn about and visit. There are many mountain ranges located in the United States, but one in particular is very interesting. Lookout Mountain is no ordinary mountain; although it was created by the same means as any other mountain, this particular landform has a different type of flair. For years, geologists have looked for existence that distinguishes mountains and caves. On December 28, 1928, Leo Lambert, found what separated Lookout Mountain from other mountains. The mountain located in Chattanooga Tennessee the Southeast region of the United States contained a water fall and cave. Lambert and his crew discovered the water fall while trying to create an elevator shaft in the Mountain. Lambert astonished by the sight, decided to name the water fall after his wife Ruby.
Ruby Falls is 145 feet in length and is located 1120 feet below Lookout Mountain’s surface. Ruby Falls is more than just a water fall, but to actually get an opportunity to view it, you would agree that this is an ideal scene of nature at its best.
The Colliding of the North American and African Plates
Tectonic Plate
A tectonic plate (also called lithospheric plate) is a massive, irregularly shaped slab of solid rock, generally composed of both continental and oceanic lithosphere. There are three types of plate boundaries: divergent boundaries, convergent boundaries, and transform boundaries. Upon collision, these boundaries form landforms. Millions of years ago the North American and African plate boundaries collided. These tectonic forces caused a series of earthquakes that pushed and bent. The rock hardened and formed what we know today as the Appalachian Mountains.
Geographically, the Appalachian Mountains are not a single continuous range but a complex group of mountains that follow the southeast coast of the North American continent. For millions of years, where Lookout Mountain stands now, was a part of a vast ocean, covering much of the interior of North America. This geologic age ended about 200 million years ago, during this time the tectonic forces created the portion of the Appalachian Mountains that we know today as Lookout Mountain. This range of mountains lies on the Chattanooga and Kingston faults.
Ruby Falls' Cave
When I think of caves, I think of dark scary places that have bats and other night creatures. Caves have existed for many years and according to www.britannica.com a cave is natural opening in the Earth large enough for human exploration. Such a cavity is formed in many types of rock and by many processes. Caves are also called caverns, and they come in all different shapes, sizes, and colors. Caves provide shelter for some people and animals, and some caves are used for entertaining purposes, and attractions. When a person thinks about caves, sometimes they wonder how it came about, and what caused the formation. There are many different types of caves like lava caves, ice caves, and caves created by the chemical reaction of groundwater and bedrock composed with limestone. The formation of caves will contain calcium carbonate. There are a lot of caves that are known for its attraction. One is the cave of Ruby Falls. According to rubyfalls.com, the Ruby Falls' cave is located deep in the heart of Lookout Mountain. Because Ruby Falls' cave is an attraction to visit, it probably does not have creatures living in it. The cave doesn’t have a natural entrance according to rubyfalls.com. Most caves are results of limestone. Ruby Falls is a limestone cave (sometimes called a solution cave).
Formation of Limestone and Ruby Falls Cave
Limestone caves are formed by the process of carbon dioxide in the air that is absorbed by rain water falling through it. The rain water also absorbs carbon dioxide that is in the soil after it hits the ground. Water then breaks carbon dioxide down into a very weak acid called carbonic acid. The weak acid comes into contact with limestone rock when subterranean streams find their way through the cracks in the limestone rock that have been produced by tectonic forces. The acid solutes (or eats away) the limestone, which is made of calcium carbonate or calcite, causing the cracks to become larger and caves and passages to form this process is called chemical weathering. As we have learned in class, the water table forms the different levels of limestone caves because of the change in sea levels, and the change in climate. It has been proven that at one time the water table was much higher and the Ruby Falls Cave was at the top of it. Rushing water flowed through for many years washing out the cave and enlarging the faults and cracks. The water table has since lowered and that explains the lack of water in the cave. Over the years, the water level in the cave lowered and air entered the Ruby Falls Cave. When that happened the conditions were right for the formation of speleothems, or cave formations. The formation process takes a very long time. It is a very simple process though: water moving through the soil absorbs the minerals in the limestone. As the water evaporates or drips it leaves minerals behind. There are many features involved in the formation of the cave. According to the geological history of Ruby Falls Cave, the stalactites form as water drips from the ceiling leaving minerals behind, the minerals build up very slowly to make the stalactite. All stalactites start out as capillary tubes (also called soda straws.) A capillary tube is a hollow stalactite. They are very thin and fragile. When the hole on the end of a capillary tube is closed off, it becomes a stalactite, and begins to widen. Capillary tubes are very common in the Ruby Falls Cave especially in the Hall of Dreams. Stalagmites are formed by minerals deposited on the floor when the dripping water hits and leaves behind minerals. Stalagmites almost always form underneath stalactites. Columns are formed when a stalactite and stalagmite grow into each other. Drapery formations (also called curtains) are formed as water works its way through the small cracks and crevices in the ceiling and evaporates before it has a chance fall. Flowstone is formed from flowing water instead of dripping water. The calcite is deposited in thin layers. These thin layers will first take the shape of the cave floor or bedrock underneath it. The flowstone builds up to become more rounded as it gets thicker. Helictites are a type of stalactite. Helictites grow in any direction on the cave ceiling. Their twisted shape is attributed to air currents and the arrangement of the crystals of calcite. As you can see, Ruby Falls' cave has unique formations and features. The attraction is beautiful and worth a drive to see.
Ruby Falls' Waterfall
The waterfall of Ruby Falls came after the formation of the Ruby Falls caves. Ruby Falls is a 145 feet underground waterfall. A surface stream entered it and left deposits of sand and gravel along the walls. At this point a sinkhole developed near the head of the stream and allowed a lot of water to enter. The presence of sand and clay along the side of the cave confirm the presence of a sink hole at one time. The water came out of the dome area where Ruby Falls is located; this area is sometimes called the “Solomon’s Temple”. Erosion helped the waterfall carve this area out. Above the waterfall there is a mineral called calcite. Calcite is the major component of limestone which is a sedimentary rock and it is involved in the formation of most waterfalls including Ruby Falls. A waterfall is a geological formation resulting from water, often in the form of a stream, flowing over an erosion resistant rock formation that form a sudden break in elevation or nickpoint. Some waterfalls form in mountain environment where the erosive water force is high and stream courses may be subject to sudden and catastrophic change.
Formation of a waterfall is when a river flows over a large step in the rocks which may have been formed by a fault line. Over a period of years, the edges of this shelf will gradually break away and the waterfall will steadily retreat up stream, creating a gorge. The rock stratum just below the more resistant shelf will be of a softer type, meaning undercutting, due to splash back, will occur here to form a shallow cave like formation known as a rock shelter or plunge pool under and behind the waterfall. The outcropping which is the more resistant cap rock will collapse under pressure to add blocks of rock to the base of the waterfall. The rocks are then broken down into smaller into smaller rocks by attrition as they collide with each other, and they also erode the base of the waterfall by abrasion, creating a deep plunge pool.
There are several different types of waterfalls listed below:
- Block: Water descends from a relatively wide stream or river.
- Cascade: Water descends a series of rock steps.
- Cataract: A large waterfall.
- Fan: Water spreads horizontally as it descends while remaining in contact with bedrock.
- Horsetail: Descending water maintains some contact with bedrock.
- Plunge: Water descends vertically, losing contact with the bedrock surface.
- Punchbowl: Water descends in a constricted form, and then spreads out in a wider pool.
- Segmented: Distinctly separate flows of water form as it descends.
- Tiered: Water drops in a series of distinct steps or falls.
- Multi-Step: A series of waterfalls one after another of roughly the same size each with its own
The Ruby Falls Waterfall is a mixture of several of the different types of waterfalls above. This waterfall consist of a stream flowing over a cliff face or slope for a long enough distance that it creates a certain amount of agitation in the water below. Ruby Falls is the world's highest underground waterfall.
References:
DeSitter, L.U. (Ed.). (1970). The tectonics of the Appalachians. New York: John Riley & Sons, Inc.
History of Ruby Falls. Retrieved July 24,2007 from,http://www.rubyfalls.com/history 2.htm
History of Ruby Falls. Retrieved July 24,2007 from,http://www.rubyfalls.com/geology 2.htm
(2007). In Encyclopædia Britannica. Retrieved June 28, 2007, from Encyclopædia Britannica Online: http://www.britannica.com/eb/article-9111019
Walker, R.S. (1941). Lookout the story of a mountain. Kingston, Tennessee. Southern Publishers, Inc.
