GEOLOGY AND GEOGRAPHY OF THE OKEFENOKEE SWAMP
This portion of the Webpage was compiled by Scott Manning. Scott Manning is a Junior from Hershey, Pennsylvania, who is majoring in Sports Medicine.
Related Maps
Islands and Praries in the Okefenokee Swamp

Proposed DuPont Heavy Minerals Mine

Map of the Okefenokee Swamp

Okefenokee Swamp in 1925

Location of Okefenokee in Georgia

The Okefenokee Swamp in southeastern Georgia covers approximately 700 square miles. It has all "the ingredients of the classic Southern swamp: the dense watery cypress swamp forests, the live oak hammocks, alligators and large wading birds, and the legends"5.

Located in the "southeastern corner of Georgia, it covers parts of Brantly, Camden, Clinch, Pierce, and Ware Counties", and extends a little into Florida5. Most of the area is managed by the Okefenokee National Wildlife Refuge that extends about thirty­eight miles from north to south and about twenty­five miles across at its widest part.

Most of the water from thunderstorms of spring and summer dump water into the swamp that is mostly evaporated or transpired by plants. The remaining water feeds the Okefenokee's rivers, mainly the Suwannee River; "less than 10 percent flows into the St. Mary's River" . The St. Mary's proceeds eastward to the Atlantic, forming the Georgia­Florida boundary along most of its course; the Suwannee flows southwestward out of the swamp across northern Florida to the Gulf of Mexico5.

The name Okefenokee, meaning "Land of Trembling Earth," was the apt and poetic designation of the Indians5. Much of the swamp is a sort of floating blankets of peat called "batteries" that rock back and forth where one attempts to walk on it, thus causing small trees and bushes to move up and down5 . The peat deposits range up to twenty­five feet in thickness. It is said that the big cypress trees are not in contact with the ground, but are rooted in the upper crust of the peat bed.

Drought and enormous fires have opened patches of the Swamp for colonization by plants and animals, periodically. New marshes, and occasionally lakes, are burned out by fires and the nutrients released by the fire renew life . Drought and fire have been a part of the swamp ecosystem from its infancy from evidence of charcoal and pollen in peat cores .

The Okefenokee Swamp is only about 7000 years old and the cypress swamp probably did not develop until about 2500 BC. People have lived near the Okefenokee Swamp area for ten or twelve thousand years, but it appears that the Okefenokee basin was relatively uninhabited for most of this time probably because of its dry condition . The oldest peat in the deepest parts of the Swamp is less than 7000 years old . For almost 3000 years, the Okefenokee was an area of marshes, shrubs, and ponds . The peaty swamp and marshes reached their present depth and margins about 3000 years ago .

It is believed that more 7000 years ago, the area that now occupies the Okefenokee Swamp was a part of the Atlantic Ocean. When the area that occupies the Swamp was a part of the Atlantic Ocean a major barrier of the shoreline was established. Today, we refer to that barrier as Trail Ridge. Trail Ridge is a "deposit of coarse sand and gravel of almost pure quartz and quartzite extending nearly 200 miles linearly along the eastern side of the Florida peninsula from the southeastern corner of Georgia almost to Lake Okeechobee" . The width of the ridge is approximately 10 to 15 miles in some areas. As the Atlantic Ocean receded along the Georgia coastline, Trail Ridge succeeded in retaining the water in the area that present day constitutes the Okefenokee Swamp. Without a doubt, Trail Ridge is a major feature that is vital to the Okefenokee Swamp.

Trail Ridge also contains rocks and minerals (zircon, staurolite, and the titanium minerals ­ ilmenite, rutile, and leucozene) that the company E. I. Du Pont De Nemours and Company, Inc. would like to mine for on 38,000 acres of the Trail Ridge over a 50 year period beginning in 2002. According to a pamphlet prepared by the U.S. Fish and Wildlife Service, the mining procedure will include:

*Clearing all vegetation in approximately one­square mile sections.

*Strip and store one foot of topsoil.

*Create a dike system around the cleared area to retain all surface water on site.

*Dredge the cleared area to a depth of 15 to 50 feet below the ground surface with a hydraulic suction cutter head dredge floating on a 20 acre dredge pond.

*Extract the valuable minerals using gravity separation techniques in a wet mill floating behind the dredge. Approximately 2­3% by volume of soil will be retained.

*Backfill the mined area.

*Replace topsoil and contouring the land to approximate pre­mine elevations and drainage patterns.

*Re­create wetlands and re­vegetate the mined area with grasses and pine trees.

It is believed that mining of the Trail Ridge will destroy the Okefenokee Swamp. Listed below from the pamphlet by the U.S. Fish and Wildlife Service are environmental concerns of the proposed mining operation.

HYDROLOGICAL ALTERATIONS:

*Alteration of surface water drainage associated with diking.

*Impacts to ground water characteristics including water table elevation, seasonal storage capacity of Trail Ridge, and rate and direction of flow as the soil profile is permanently homogenized 50 feet deep.

*Destruction of water confining or perching layers.

*Disruption of surface water/aquifer interactions.

*Changes in the water holding capacity and water level of the swamp.

*Impacts of pumping of up to 750,000 gallons per day of ground water

*Potential for increased fire frequency and intensity in the Okefenokee Swamp and surrounding private commercial forest associated with the changing of hydrology.

ENDANGERED SPECIES CONCERNS:

*Loss of habitat for, and destruction of, existing populations of red­cockaded woodpeckers, indigo snakes, wood storks, and other protected or sensitive species.

*Increased pressure on the small upland habitat areas of the refuge.

WETLAND DESTRUCTION:

*Destruction of thousands of acres of wetlands contiguous with Okefenokee Swamp.

*Destruction of isolated wetlands on the Trail Ridge.

WATER QUALITY DEGRADATION IN THE OKEFENOKEE SWAMP AND ST. MARYS RIVER:

*Mobilization of contaminants (e.g., herbicides, insecticides, mercury, and iron) presently attached to soil particles.

*Increased siltation and turbidity of adjacent water bodies during land clearing and reclamation.

*The potential for dike breaches.

*NPDES discharge and seepage from sedimentation ponds.

*Release or spills of oil, grease, and hydraulic fluids from mining equipment.

*Increased use of fertilizers in timber operations after mining and the resultant nutrient loading.

AIR QUALITY DEGRADATION IN THE OKEFENOKEE WILDERNESS AREA:

*Mine generated dust, smoke and soot as the land is cleared, worked, and restored.

*Exhaust and dust from mine vehicles and heavy equipment.

AESTHETIC CONCERNS:

*Impact of noise pollution on visitors' wilderness experience.

*Light pollution from the 24 hour mine operation.

*Degradation of scenic views.

The mining of Trail Ridge may also damage the Floridan Aquifer. The Floridan Aquifer is the source of water for many communities. The problems that may cause water quality degradation to the Okefenokee Swamp and the St. Mary's river could have a vast impact on the portion of the Floridan Aquifer that rests below the Okefenokee Swamp region. For example, seepage to the Floridan Aquifer from the DuPont mining region that may inadvertly release or spill oil, grease, and hydraulic fluid from mining equipment may vastly affect the quality of the water that is within the Floridan Aquifer.

REFERENCES

1. DuBar, Jules R. and Oaks, Robert Q. Jr. Post Miocene Stratigraphy Central and Southern Atlantic Coastal Plain.

Utah State University Press: Utah, 1974. 21­26.

2. Meanley, Brooke. Swamps, River Bottoms and Canebrakes. Barre Publishers: Massachusetts, 1972. 13­26.

3. Pamphlet on the Proposed E.I. Dupont De Nemours and Company, Inc. Titanium Mining Project, Charlton County, Georgia, by the U.S. Fish and Wildlife Service. April 4, 1997.

4. Trowell, C. T. Okefenokee: The Biography of a Swamp. C. T. Trowell: Georgia, 1989.

5. Wright, Albert H. Our Georgia­Florida Frontier: The Okefinokee Swamp Its History and Cartography Part 1. A. H. Wright: New York, 1945.6