Ruby Falls Earthcache EarthCache

RUBY FALLS

Man has always admired the beauty of the Earth’s natural wonders. But there are wonders that, if not for some small circumstance, man would never have the opportunity to see. Ruby Falls is one such wonder. Mired in an intriguing history as well as natural beauty, Ruby Falls is one of the staple attractions for tourism in Chattanooga Tennessee. Formed over millions of years by the Earth’s physical forces, Ruby falls was scoured out of solid rock, transforming it into something that words cannot adequately describe.

The history of Ruby Falls begins about 540 million years ago, in the Cambrian period. At that time, the area that is now Tennessee was the floor of a warm, shallow ocean, Laden with all kinds of marine life. On the ocean floor settled layers of sediment and the shells of deceased sea creatures. These shells consisted mainly of calcium compounds. over the next 300 million years, the layers built up, and as they did so, they compacted the layers below. The increasing pressures transformed the calcium rich layers into limestone (calcium carbonate), a soft mineral rock that is very reactant to acids.

At the time that these layering processes began to occur, Plate tectonics was also playing a part in the Ruby Falls formation. As the millions of years passed, tectonic activity drifted the plates composing the earths crust. At some points the plates separated, and at some points the plates collided, causing one to slide under the other in what is known as a subduction zone. The upper plate in such a zone buckles and is forced upward to form mountains. This is how the appalachian mountains, and Lookout Mountain in which Ruby Falls is found, were formed.

As the Appalachian Mountains were pushed up from the sedimentary rock by tectonic forces, the limestone and sandstone that they were made of developed cracks that filled with ground water. Now elevated high above the surrounding terrain, gravity pulled this water downward through the cracks in the mountains, creating flows within them. The ground waters contained carbon dioxide which entered the waters through the waters interaction with the atmosphere and the biological processes of organic carbon digestion (rotting vegetation) and photosynthesis. The carbon dioxide contained within reacted with the water, creating carbonic acid, a weak acid that is key to the formation of caves. This reaction is defined in the general empirical formula:

water + carbon dioxide = carbonic acid

H₂O + CO₂ = H₂CO₃

Slowly, the water and the carbonic acid dissolved within began to erode the limestone (calcium carbonate or calcite) around the underground flows. This reaction produces calcium bicarbonate, which is much more soluable in water, according to the general empirical formula:

carbonic acid + calcium carbonate = calcium bicarbonate

H₂CO₃ + CaCO₃ = Ca(HCO₃)₂

The water nows carries the dissolved calcium bicarbonate away to be deposited elsewhere. This process is incredibly slow. But, as the eons passed this process gradually increased the size of the cracks and allowed more water in. The waters, as most things in nature, tend to travel the path of least resistance. Therefore larger cracks contained larger flows and acted as arteries; collecting ground waters form many other smaller cracks. At certain points, where the flows changed direction, turbulent flow was created, increasing the amount of erosion in those areas. This erosive process formed caverns containing underground rivers, as illustrated below :

Later, the water levels within these caverns receded, creating voids. These voids allowed the carbon dioxide trapped in the ground waters to evaporate and fill the voids. The ground waters continued to seep in, carrying minerals dissolved from the earth with them. As they seeped in, the minerals within could again react with the carbon dioxide in the void, creating compounds that were deposited at the points of entry. Again over time, these deposits grew in size and took various forms as speleothems, or cave formations. These formations include: capillary tubes, stalactites, stalagmites, columns, drapery formations, flowstones, and helectites (see below for descriptions of each). Speleothems that are white in color indicate calcium carbonate deposits. Reddish or brown speleothems indicate the presence of iron. All of these formations can be seen during a tour of Ruby Falls.

It is awe inspiring to think of how long it took such weak forces to do so much work. It is also amazing to think that man would have never had the chance to see this wonder if it had not been for the initiative of one man, Leo Lambert, whose vision is responsible for Ruby Fall’s discovery. The Story of how he came to discover Ruby Falls is almost as amazing as Ruby Falls itself. You can read his story on the Ruby Falls website.

To log this Cache:

1. Visit Ruby Falls. There is an admission cost, but it is worth it for the 1 ½ hour guided tour and use of the other facilities. Go to the Ruby Falls website (www.rubyfalls.com) beforehand. This is important. It gives more complete information on visiting Ruby Falls. Pay particular attention to rates, hours of operation, tour length, clothing restrictions, and the facilities available.
2. Post a picture of yourself inside of Ruby Falls in your log. (The on-site professional photos are not required).
3. Answer three questions (not in your posts, please. E-mail the owner through the GC website):
   • What is the main chemical involved in the erosions process of the rock? (name or formula)
   • To Understand how slow these processes are, there is a STALAGMITE (the things that grow from the floor up) inside of Ruby Falls that is pictured in the gallery of this cache page. Estimates of stalagmite growth range from 150 to 1500 years per cubic inch. If we model this stalagmite as a cylinder 6 feet tall and 1 foot in diameter, even at the slowest rate is its consistent with the age of Ruby Falls? Ruby Falls itself is estimated to be over 30 million years old.
   • What is the name of the formation pictured below? How do you think it obtained its shape?

Enjoy!

NOTE: If you are logging as a group, the person sending the answers must reference each individual in the group. No "I'm with him" logs.

Thanks to C Squared Team for posting the photo of Ruby Falls which I used on this page!

Administrative information:

• Hours of operation: 8-8 every day except Christmas
• Admission: $21.95 per adult; $12.95 per child
• Parking is free (first come first served)
• Tours begin every 15 minutes and last 1 ¼ to 1 ½ hours
• Facilities include: Grill, coffee shop, gift shop, lookout tower,kids activities
• Clothing: wear rugged clothing and a light jacket. Temp inside is 58 degrees
• Ruby Falls is not handicap accessible
• Strollers are not allowed
• Pets are not allowed
• Cameras and Video are allowed

Glossary terms:

• Capillary Tubes: The first stage of growth of a stalactite, a narrow fragile formation that is hollow.
• Cave: A natural underground chamber or series of chambers usually open to the surface.
• Column: A pillar-like structure formed when a stalactite and stalagmite have met and joined together.
• Curtain: A thin translucent sheet of calcite formed when water flows down the inclined ceiling of a cave (drapery).
• Erosion: The process by which weathered materials are carried away by wind, water, or glaciers.
• Flowstone: A surface coating or a calcite layer that has been deposited by a descending film of mineral-charged cave water.
• Helictites: A distorted and twisting stalactite that grows with a seemingly disregard of the pull of gravity.
• Limestone: A sedimentary rock composed chiefly of the mineral calcite. It is easily dissolved by acidic ground water. Most of the world’s caves are formed in limestone.