Post by L Roebuck on Jun 19, 2006 7:39:57 GMT -5
Beneath us lies a world of water and caves
By Jennifer Portman
Democrat Senior Writer
Northern Florida may not have impressive geologic features aboveground, but it's a different story below.
Much of it sits atop dissolving limestone riddled with caves, crevasses and conduits, coursing with freshwater that erupts at more than 700 known springs.
The term "karst" describes such places, where the only thing between surface-water runoff and the groundwater aquifer can be a few feet of sand. In some places in this sinkhole landscape there's nothing at all between aquifer and sky.
Southern Leon and Wakulla counties are part of the 280,000-acre Woodville Karst Plain. Wakulla Springs is its superstar, but the karst plain is also home to a quarter of Florida's biggest springs, pumping more than 2 billion gallons of water a day.
At the plain's northern boundary is the Cody Scarp, the edge of an ancient sea that cuts across southern Leon at about the North Florida Fairgrounds.
North of this escarpment is a layer of clay that confines groundwater. Below it is sand. Water moves more easily through sand. So water that falls south of the Cody Scarp enters the aquifer - and springs system - much more quickly.
Full Article and Photo Galleries:
www.tallahassee.com/apps/pbcs.dll/article?AID=/20060618/NEWS01/606180314/1010
By Jennifer Portman
Democrat Senior Writer
Northern Florida may not have impressive geologic features aboveground, but it's a different story below.
Much of it sits atop dissolving limestone riddled with caves, crevasses and conduits, coursing with freshwater that erupts at more than 700 known springs.
The term "karst" describes such places, where the only thing between surface-water runoff and the groundwater aquifer can be a few feet of sand. In some places in this sinkhole landscape there's nothing at all between aquifer and sky.
Southern Leon and Wakulla counties are part of the 280,000-acre Woodville Karst Plain. Wakulla Springs is its superstar, but the karst plain is also home to a quarter of Florida's biggest springs, pumping more than 2 billion gallons of water a day.
At the plain's northern boundary is the Cody Scarp, the edge of an ancient sea that cuts across southern Leon at about the North Florida Fairgrounds.
North of this escarpment is a layer of clay that confines groundwater. Below it is sand. Water moves more easily through sand. So water that falls south of the Cody Scarp enters the aquifer - and springs system - much more quickly.
Full Article and Photo Galleries:
www.tallahassee.com/apps/pbcs.dll/article?AID=/20060618/NEWS01/606180314/1010