Fact Sheet

Little Salt Spring
Panoramic view from the west edge across the spring basin

Official Name Little Salt Spring Archeological and Ecological Preserve
Location Southern Sarasota County, Fla.
Acreage ~111 acres
Surface Diameter ~240 feet (70 meters)
Depth range 200 – 250 feet (60–76 meters)
Source Anoxic groundwater from the base of the Floridan Aquifer
Shape Little Salt Spring possesses a funnel-shaped upper basin (0–45 feet/0–14 meters deep) containing a lacustrine sediment sequence from 3–13 feet/91–396 meters thick. At a depth of 90 feet (27 meters) below the spring surface is a natural ledge. The bottom of the spring measures approximately 240 feet (73 meters) in diameter at 200–250 feet (60–76 meters).
Chemical Properties Total dissolved solids avg. 3,000 Mg/l
Average Water Ph 7.6 – 8.1 (1962–1972)
Geological Properties Cover-collapse sinkhole in limestone strata of the Hawthorn Group (Miocene).
Age of Spring More than 15,000 years, near the end of the last Ice Age.
Biological Properties South Florida pond ecosystem in the upper 1–15 feet (30–457 centimeters), surrounded by undisturbed South Florida hydric hammock vegetation community.
Artifacts Artifacts found in the upper basin (0 – 45 feet/0 – 14 meters deep) have been dated back to the Middle Archaic period ~ 6,000 – 11,000 calendar years Before Present (BP). At the ledge, bones of extinct late Pleistocene animals and at least one wooden artifact have been recovered. Radiocarbon dating placed them at 14,000 calendar years BP.
Light level at bottom Near zero
SCUBA Diving Archaeological work on the ledge requires Nitrox; exploration of the spring’s bottom involves technical open-circuit Trimix diving, and specialized cave diving training.
Landowner University of Miami, Rosenstiel School of Marine & Atmospheric Science
Principle Investigator John A. Gifford, Ph.D.
Diving Safety Officer Rick Riera-Gomez, Jr.

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