News Release 495

DEPARTMENT OF NATURAL RESOURCES PRESENTS
PAPERS AND POSTERS AT
NATIONAL KARST MANAGEMENT SYMPOSIUM

Volume 35-495

Contact: Hylan Beydler

(For immediate release)

573-368-2118

ROLLA MO, OCT. 31, 2007—Department of Natural Resources staff from the Division of Geology and Land Survey in Rolla attended the 2007 National Cave and Karst Management Symposium, October 8 through Oct. 12 in St. Louis. Four geologists who deal with environmental challenges associated with the karst landscape in Missouri presented information at the symposium. Also participating were speakers representing other karst areas, including the Virginias, Kentucky, New Mexico, Oregon, Tennessee, Texas and the Yucatan peninsula.

Jerry Prewett's presentation was entitled, "Soil-Cover Karst Collapses in Missouri." Soil-cover karst collapses are naturally occurring, geologic conditions that may result in property damage or may be a threat to the safety of citizens or animals. Prewett spoke specifically about the geologic hazards associated with sinkholes such as the sinkhole collapse Aug. 13, 2006, in Nixa that was responsible for the loss of a home and automobile parked inside the attached garage. The sinkhole was initially estimated to be approximately 60 feet in diameter and 75 feet deep. While sinkholes are common in karst areas such as the Missouri Ozarks, the sudden collapse of one beneath a home is not a common occurrence.

Neil Elfrink spoke about, "Transverse Speleogenesis in the Ozarks." Elfrink explained speleogenesis as a primary process that can help form essential features of the landscape in karst areas. Elfrink asserted that the role of discharging groundwater on landscape development might have been overlooked. He offered a new theory supported by data collected by the U.S. Geological Survey that provides an entirely different view of landscape evolution. He explained that the newly released study on Big Spring has determined that water making up the spring's huge base flow may have been underground for several hundred years. This old, pressurized water moves upward from deep aquifers and combines with modern surface precipitation entering sinkholes and losing streams to form bedrock meanders. Surface streams tend to meander from spring to spring at times engulfing a spring, masking the role that is played by underground waterways. Thus, the meandering valleys that are a trademark of the Ozarks are primarily a consequence of springs and karst processes that lower the landscape and direct valley alignment as the streams incise or form.

"Stable Carbon Isotope Characteristics of Central Missouri Caves" was the title of Jeff Crews' presentation. Crews talked about how carbon isotope ratios of various Missouri cave waters change with the seasons and how these changes are controlled the number of and distances to cave entrances. The current use of speleothems as a record of past climate assumes that carbon isotope signatures recorded by speleothems are controlled by the type of plants growing above the cave and that the water changes slowly over time. In addition his work with the department, Crews is serving as president of the Missouri Speleological Survey. MSS coordinates the efforts of various caving groups in the state, encourages and initiates constructive activities such as cave science projects, mapping and description of caves, and serves as a repository for cave data gathered by individuals and caving clubs.

Larry Pierce participated in a poster session, "A Case Study for the Use of Groundwater Tracing in the Investigation and Enforcement of Missouri's Environmental Regulations." The department's Division of Geology and Land Survey water tracing methodologies have been developed over a period of four decades to improve the quality of data collected on groundwater movement. The department maintains a dye trace database containing information on nearly 500 dye traces. Geologists, hydrologists and other technicians and professionals need this information for environmental protection efforts.

Other presenters spoke about topics ranging from protecting endangered species and fixing broken stalagmites to methods for mitigating these threats and ways to recover losses. Several field trips were held in conjunction with the symposium and were open to the public. A tour of Fisher Cave in Meramec State Park near Sullivan was the highlight of the trip. Several of the program geologists went on a karst tour that had stops at several karst features that have presented engineering challenges. The Missouri Department of Conservation and the Missouri Caves and Karst Conservancy hosted the symposium. The Department of Natural Resources manages Meramec State Park.

The department's Division of Geology and Land Survey is online at www.dnr.mo.gov/geology. For news releases on the Web, visit www.dnr.mo.gov/newsrel. For a complete listing of the department's upcoming meetings, hearings and events, visit the department's online calendar at www.dnr.mo.gov/calendar/search.do.

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