Virginia Cave Owners' Newsletter April 2012 VIRGINIA CAVE OWNERS’ NEWSLETTER Table of Contents
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Virginia Cave Owners' Newsletter April 2012 1 VIRGINIA CAVE OWNERS’ NEWSLETTER Table of Contents April 2012 A publication of the Virginia Cave Board, Department of Conservation and Recreation No. 24, April 2012 1 Letter From the Former Chairman 1 Chairman's Column 2 Determining the Age of a Cave Hike the Karst Trail! 4 An Update on White-Nose Syndrome in Virginia Getting out and or getting “in”—into a show 4 Dr. David S. Blehert Talks About White-Nose Syndrome cave or cave exhibit—is the underlying idea 6 Coming Soon: Karst Trail Website! behind this year’s theme for the annual cel- 6 How Karst Shaped the Civil War in Virginia ebration of Virginia Cave Week. This year 8 Virginia Cave Board Policy on Algae Abatement Cave Week is April 22–28, 2012. Dixie Caverns, Grand Caverns, and Shenandoah Caverns are all offering Cave Thanks to contributors: Babs Bodin, Dr. Dan Week discounts again this year. Ask for your Doctor, Thomas Lera, Judy Molnar, Wil Orndorff, and Cave Week discount when buying tour tick- Meredith Hall Weberg ets. Get out or IN and learn about caves and karst in the Commonwealth! Letter From the Former Chairman by Thomas Lera This is my last column, as I have come of having a strong board chairman, as it achieving consensus and unity, motivate to the end of my five and a half years is the most strategic in the organization. them to carry out their projects, and stay service as Chairman of the Virginia We are fortunate to have Meredith Hall informed on issues relating to the caves Cave Board. It has been both a pleasure Weberg as the new Virginia Cave Board and karst. and a privilege to serve in this office and chairman. She is a true friend and I will This is your Board and I hope you all to have met many of you at national, work with her to achieve her goals for continue to support it and Meredith in regional, and local events. I know there the Virginia Cave Board. the future as strongly as you did me in is still enormous goodwill and support I know she will work closely with the the past. I look forward to serving on the out there for the Board to both represent State, National, regional, and local board and working with you all for many you and lobby the State on your behalf. associations and groups, chair board more years. I will not bore you with our meetings, and act as a spokesperson accomplishments over the last five for the VCB to the community. Meredith years. Rather I will stress the importance will also guide fellow Board members in Chairman’s Column the rest of the Board thinks I will do a good job. I will do my best. by Meredith Hall Weberg I was rather surprised to be asked to Already I have run a couple of meet- Tom was too kind in his last column; I “run” for Virginia Cave Board (VCB) ings and written a couple of letters on hope I can live up to his glowing words. chairman, but also very honored that behalf of the VCB, one hard and one Virginia Cave Owners' Newsletter April 2012 2 easy. The hard letter was written by two VCB is, after all, dedicated to Virgin- What I’m trying to say is that the Vir- of our Board member scientists and ia’s cave landowners. Please contact ginia Cave Board exists to serve you, was one of the more difficult things I’ve us if you have questions, want informa- Virginia’s owners of caves. Please let ever edited. You must keep your reader tion, or need our help with anything. We us know how we can help. in mind when writing and I could not are here to help you take care of your understand some of how they phrased cave(s). (The small graphic next to the article things. I think it turned out well because I hope you enjoy reading the articles title is the cave map symbol for I had a lot of help; in fact, the gist of that in this issue of the Virginia Cave Own- columns, speleothems that are formed letter is now VCB’s policy on cleaning ers’ Newsletter. I enjoyed editing them. when a stalactite grows down and a “lampenflora” (algae!) from show caves You see, I am also the editor for VCB. I stalagmite grows up, and they meet in and is included elsewhere in this issue. would love to hear from you in that ca- the middle.) The easy letter was a “thank-you” to the pacity as well, especially with sugges- Blue Ridge Grotto, a cave club based tions for articles or if you want to write in the Roanoke area, for its donation to an article yourselves! Maybe one of you VCB for our good work of helping YOU cave owners out there has a unique sto- with your stewardship of our Common- ry or situation related to owning a cave wealth’s caves. that you want to share with others. Determining the Age of a Cave By Dr. Dan Doctor, Virginia Cave Board “How old is the cave?” This question younger than about 200 million years. This is a stalag- often comes to the mind of the curious But how old is the space itself? The mite from Grand cave visitor. It is not a simple question best we can do is determine a minimum Caverns. This to answer, because caves can form age of a cave by determining the age photo shows over time spans of thousands, some- of items within it. These items can in- the stalagmite times millions of years. What makes the clude human artifacts, animal bones or sliced in half, question even more difficult to answer is other remains, and mineral or sediment illustrating the the fact that it is impossible to provide a deposits that lend themselves to dat- growth layer- date on what is no longer there; a cave, ing by geochemical methods. When we ing. The top after all, is mostly empty space. A slight- are lucky enough to find such items in has been dated ly easier question to answer is, “What is a cave, undisturbed and in their original to be 12,800 the age range of this cave?” By dating place of rest or deposition, we can be- (+/- 100) years the materials we find in caves, we can gin to piece together the history of the old and the bot- say with confidence that the cave is at cave. Although human and animal arti- tom is 66,500 least as old as the things found within facts are very useful, they usually only (+/- 500) years it and must be younger than rocks that provide information on the most recent old. (dating by contain it. period of the cave’s history, the time Dr. Yongli Gao, In Virginia, most caves are formed since the cave was open at the surface East Tennes- within limestones that were deposited and accessible to entry. To go further see State Uni- as marine sediment during the Paleozo- back into geologic time, geochemical versity) ic era of geologic time, between about age-dating of mineral deposits is nec- 570 and 350 million years ago. Fos- essary. sils and radiometrically dated volcanic ash beds sandwiched among the lime- DATING SPELEOTHEMS the weight of a person is measured in stone layers provide direct evidence In order to directly measure the age of pounds or kilograms, the weight of an of the age of the rock layers, or strata. a speleothem (stalagmite, stalactite, atom is the total sum of proton and neu- The sedimentary rock strata were later or other mineral formation in a cave), trons in its nucleus, and this number is deformed during the building of Appa- geologists measure concentrations of the atomic mass. For example, an atom lachian Mountains, which occurred ap- radioactive elements and their decay of uranium-238 (or 238U) has an atomic proximately between 320 to 220 million product isotopes that are part of the mass of 238, with 92 protons (which years ago. Nearly all caves in Virginia chemical makeup of the mineral itself. defines the atom as uranium) and 146 show passages that follow fractures and Isotopes are atoms of a particular ele- neutrons. If the nucleus of an atom is folds that formed in response to the de- ment that, because of different numbers unstable, it will spontaneously give off formation associated with the mountain of neutrons in their nucleus, have differ- some particle or amount of energy. This building, thus the caves are very likely ent atomic weights, or masses. Just like process is called radioactive decay. Virginia Cave Owners' Newsletter April 2012 When radioactive decay of an atom oc- curs, the initial atom does not simply disappear; rather, it changes into an- other isotope of that element, or into an isotope of another element. As decay product isotopes build up in a mineral over time, the amount pro- duced provides a record of how much time has passed. This is because radio- active elements decay over well-defined periods of time. The rate of radioactive decay is measured in half-lives, or the amount of time needed for half of the ra- dioactive substance to decay away. The longer the half-life, the greater the age of the material that can be dated. For example, the radioactive isotope of car- bon, carbon-14, has a half-life of 5270 years, and is useful for dating materials less than about 42,000 years old.