THE GEOLOGY OF FALLING WATERS
STATE RECREATION AREA
by
Frank Rupert, P.G. No. 149 and Ed Lane
Falling Waters State Recreation Area aptly derives its name from one of Florida's most interesting geological features. The centerpiece of the park is the 100-feet deep, 20-feet diameter vertical Falling Water Sink, into which a small stream cascades during the wet seasons. The water falls into the sink and disappears underground into a maze of subterranean caverns developed in the 30 million year old limestone which underlies the region. Falling Water Sink owes its existence to a unique and fascinating geologic history.
GEOLOGIC HISTORY
The region surrounding Falling Waters State Recreation Area is underlain by ancient marine limestone. Limestone visible in the park today is comprised largely of the calcium carbonate shells of sea creatures which lived in the shallow seas covering northern Florida between 20 and 30 million years ago. As the animals died, their shells settled to the sea floor, slowly building a thick sequence of limestone. Some of these limestone strata are exposed in the walls of Falling Water Sink.
Over the succeeding millions of years, the sea advanced and retreated many times. During low sea level, when the ancient sea floor was exposed as dry land, erosion and weathering removed portions of the deposited sediments. During periods when sea levels were higher, more sediments, such as limestone, sands and clays, were deposited on top of the older limestone. These, too, were eroded during intervening periods of low sea level. Therefore, only a partial, sporadic record of the last 30