The Bottom of the Sink

We did not expect to be able to see anything in the river. Typically, the Aucilla is blackwater, stained by tannins leeching in from the swamp. In previous years, divers needed powerful lights to work even just 15 to 20 feet from the surface. This was not a typical year. The climate worked in our favor; the lack of rain kept the water clear and turbidity low. Usually we had 10 to 15 feet of visibility, depending on tide. On the best days you could stand on the pontoon boat and watch divers working in the units below.

Project PI Jessi Halligan investigates a layer of peat on the bottom of Wayne's Sink. - 2011 © Douglas Inglis

Jessi Halligan, the project PI, was thrilled with diving conditions. We were able to quickly assess the stratigraphy of the sink and position excavation units to answer our geological questions. Sinkholes like Wayne’s Sink are collapsed limestone caverns. In time they fill in with rotting biological material, slumps and river deposits. To understand the archaeology, we need to determine how the sediments formed and changed over time. There have been three major periods of infilling in Florida sinkholes: from 43,000 to 36,000 years ago, 32,000 to 24,000 years ago, and from 15,000 to 9,000 years ago. It is this last, most recent period that is the target of our investigation.

Lithic debitage, turtle shell and a glass bottle on the bottom of Wayne's Sink. - 2011 © Douglas Inglis

The bottom of the sink is littered with artifacts. Much is random debitage, deposited during slumps or blowouts, but there are more complex items as well, including bone pins and tools. Ancient turtle shell is ubiquitous, and there are numerous concentrations of fossilized bones. Mixed in with the prehistoric artifacts are lots of bottles and broken glass. We even recovered a bedraggled Etch-a-Sketch. To give you an idea of the concentration of material, the surface of a single 1m x 1m unit yeilded eight 1 gal. bags of debitage, bone, shell and glass alone. Sadly, most diagnostic artifacts have long since been collected off the site.