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IntroductionShenandoah Caverns and American Celebration on Parade offer an exciting and varied opportunity to combine earth science, history, and simple mechanics in one field trip experience. This teacher packet will provide you with some important resources to enhance the experience before your visit and in follow up classroom activities. Cave VocabularyAlabaster – Hard compact calcite or aragonite that is translucent.Anthodite – Thin crystal strains found in clusters on cave ceilings that can resemble flowers. Bacon Formations – A beautiful thin, translucent sheet of calcite deposited as water drips from slanted ceilings. Minerals, such as iron oxide, are sometimes present in addition to the calcite, forming dark brown or orange bands that resemble bacon. Botryoids - Also known as cave coral, and formed at or under water level. Air bubbles surrounded by calcium carbonate solution solidify leaving round nodules. Calcite – The most common mineral found in caves, it is made up of calcium carbonate and may take a sparkling, crystalline form. Shenandoah Caverns has some of the most beautiful crystalline formations in the world. Carbonic acid – Acid formed by rainwater picking up carbon dioxide from the air and from decaying plants and animals as it seeps through the soil. When it reaches the limestone under the soil, the acid enters into cracks and dissolves the limestone away to create the rooms, passageways and speleothems of a cave. Cave – A naturally formed cavity in the ground, large enough for humans to enter. Shenandoah Caverns is actually a series of such cavities or “rooms.” Cave and cavern have the same meaning. Column – This formation is caused when a stalactite and a stalagmite grow together or when a stalactite grows all the way to the floor. Drapery – Thin sheets of calcite that hang in delicate folds. Flowstone – This formation looks like a solid waterfall, formed when water flows over walls and other formations, building up sheets of calcite. Helictite – A formation that crystallizes in a twisted and curled fashion, defying the laws of gravity. Scientists still do not agree on how they are able to grow in this fashion. Karst – A land area that includes sinkholes, springs, sinking streams, and caves. Limestone – A sedimentary rock composed mainly of calcite. Most Virginia caves are formed from limestone. Mississippian Period – A period 350 million years ago when a sea covered the southeastern portion of the North American continent. The sea was full of tiny organisms whose shells consisted of calcium carbonate. As these organisms died, their hard shells accumulated to help form fossil-rich limestone. Rimstone – deposits of calcite formed from slow moving water. Sinkhole – Bowl-shaped depressions in the ground created by caves collapsing below ground. Sinkholes guide water into the caves below like a funnel, possibly allowing sewerage, animal waste, pesticides and other pollutants into the groundwater supply. Shield – Formed when water is forced out of a crack in the cave wall. Over time a plate begins to grow away from the wall. Soda Straws – These thin, hollow stalactites look like drinking straws and are about ¼ inch in diameter. Water runs down inside them and deposits calcites in rings at their tips. Speleothem – Formations in a cave caused as minerals are deposited by water. Spelunker – A person who explores caves. Stalactite – This formation hangs down from the ceiling. Stalagmite – This formation grows up from the cave floor. What is karstland and why is it important?(courtesy of Cave Conservancy of Virginia)Karst is a landscape that that includes topographc depressions as sinkholes and caves caused by the underground solution of limestone bedrock. This landscape features underground streams and aquifers that supply the wells and springs providing drinking water to communities. The hollow nature of karst terrain means it has a very high potential for pollution. That’s because streams and surface runoff that enter sinkholes and caves bypasses the natural filtration through soil and will move quickly through underground networks delivering contaminants to wells and other sources of drinking water. Approximately 10% of the earth’s surface (20% of the United States) is composed of karst. However, about 25% of the population lives in those areas, indicating the importance of pollution control. How karst and caverns were formed (courtesy of Cave Conservancy of Virginia) Hundreds of millions of years ago, the area now occupied by the eastern United States was covered by a calm, shallow, tropical sea. Over eons, the deposits of calcium-rich shells and skeletons solidified into the bedrock we call limestone, dolomite and gypsum. These rocks are soluble in dilute acids. Water becomes slightly acidic when it takes up carbon dioxide while passing through the atmosphere and through organic soils. The interaction of acidic water with soluble rock produces the landscape known as karst. During the Appalachian Orogeny, a series of mountain-building events in the central and eastern United States, rocks were alternately buried, uplifted, faulted, folded and fractured. This activity created cracks and fissures through which water flowed, dissolving the organic limestone. Within the past ten million years, caves, conduits and underground drainage systems have been carved into the rock by moving water. As the cracks enlarge, they eventually meet, grow larger and form a funnel-shaped hole. As the funnel becomes larger, allowing more water to move through, the water begins moving sideways, between layers of stone, always dissolving the limestone and enlarging the holes. The cracks become crevices. The crevices become channels. The channels become tunnels.
Earth Sciences Week/Virginia Cave Appreciation WeekAGI
Earth Science Week 2004 Kit ($4.95) Resources & LinksClass Exercise - Download and print a class exercise for your students to complete while touring the caverns. The free Acrobat reader is required, download that here. US Geological Survey (A Teachers Guide to Caves) American Geological Society (Earth Science Week materials) Cave Conservancy of the Virginias 13131 Overhill Lake Lane, Glen Allen, VA 23059 804-798-4893 4138 Dark Hollow Road, McMinnville, TN 37110 931-668-3925 Project Underground 2281 Lubna Drive, Christiansburg, VA 24073 540-381-8234 Virginia Cave Board Department of Conservation & Recreation Division of Natural Heritage, Main Street Station Suite 312, 1500 E Main Street, Richmond, VA 23219 |
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| Shenandoah Caverns, Inc. 261 Caverns Road Shenandoah Caverns, VA 22847-9997 PH: 540-477-3115 FAX: 540-477-3011 |
 Site Map |
American Celebration on Parade 397 Caverns Road Shenandoah Caverns, VA 22847-9998 PH: 540-477-4300 FAX: 540-477-4305 |