February 4, 1999
99-66

Jennifer Tanner
Communications Specialist

VSU professor's sinkhole research targets southern Lowndes County

Dr. Drew Hyatt is fascinated by the structure of sinkholes, and interested in how they may be conduits for polluting our drinking water.

The assistant professor in the Valdosta State University Physics, Astronomy and Geosciences Department went on an expedition to study the earthen marvels in December and early January-making the short trek to southern Lowndes County. Hyatt and colleague Dr. Robert Gilbert from Queen's University, Kingston, Ontario, Canada, conducted seismic mapping beneath five lakes in the Lake Park area-all likely formed by sinkholes thousands of years ago. Hyatt investigated the thickness of the sediment, trying to learn more about how surface water can use the caved-in soil to seep quickly into the deep groundwater aquifer that underlies Valdosta.

"These lakes represent critical access points where contaminated surface water potentially could compromise the quality of Valdosta's primary source of drinking water," Hyatt said.

While Hyatt's research focuses on the environmental record of sinkholes, his data on groundwater interaction may be useful to researchers who specialize in groundwater pollution.

"There is very interesting information in these sediment layers that can tell us how the environment has changed over time," Hyatt said.

By using a device that transmits an acoustic energy pulse through the water and then the lake bottom, Hyatt is constructing images of the sinkholes' structures. When completed, the images will hopefully provide a better view of how surface water can make its way through the soil below, Hyatt said. Preliminary results are expected to be presented in the fall.

Hyatt, who joined the VSU faculty in 1993, began extensively researching South Georgia sinkholes during the Flood of 1994. Hyatt and colleagues studied some of the more than 300 sinkholes that collapsed around Albany as heavy rainfall from Tropical Storm Alberto and overflow from the Flint River saturated the soil. The large caverns in the soil, which can appear on the surface without warning, are usually formed when an open cavity is left under a weak topsoil layer. Large amounts of rainfall can weaken the soil, causing the top layer to collapse into the cavity below-taking everything on the surface with it.

In the future, Hyatt plans to continue his studies of sinkholes in the South Georgia region. He would also like to pursue the creation of "sinkhole susceptibility maps" for Lowndes County. Hyatt explained that once you know where past sinkholes have formed, and if you take into account factors like soil composition and sediment thickness, it may be possible to predict where future sinkholes will form. This could have practical applications for businesses and homeowners in sinkhole-prone areas, Hyatt said.

For more information on Hyatt's sinkhole research, go to his Web page: http://www.valdosta.edu/~jhyatt/