Geoarchaeological Investigations into Paleoindian Adaptations on the Aucilla River, Northwest Florida

This dissertation addresses how Paleoindians used the karst drainage of the Aucilla River in northwestern Florida during the Pleistocene/Holocene transition (approximately 15-10,000 14C yr B.P.). I take a geoarchaeological approach to discuss Paleoindian land use by first defining the Late Pleistocene and Holocene geological record, and then by creating a model of site formation processes in the Aucilla River.

Both underwater and terrestrial fieldwork were performed. Underwater fieldwork consisted of hand-driven cores and surface survey, vibrocoring, underwater 1 x 1 m unit excavation, and controlled surface collection. Terrestrial fieldwork consisted of shovel and auger test pits. Seventeen cores were collected from five different submerged sinkhole sites, which were used to select two sites for further study: Sloth Hole (8JE121), which had been previously excavated, and Wayne's Sink (8JE1508/TA280), which was recorded but not formally investigated. Five vibrocores and two 1 x 1m units were used, with previous research, to define the geological and geoarchaeological context of Sloth Hole. Fifteen vibrocores, six 1 x 1 m excavation units, and ten 1 x 1 m surface collection units were used to define the geological, geoarchaeological, and archaeological context of Wayne's Sink. A combination of 130 shovel and auger test pits was used to define the geological, geoarchaeological, and archaeological potential of the terrestrial landscape. Five new Holocene-aged terrestrial sites were recorded.

All of these data were evaluated with archival data from previously-excavated sites to create models of site formation and Paleoindian land use in the lower Aucilla Basin. This research shows that there have been four major periods of sinkhole infill in the lower Aucilla basin. The first occurred prior to the Last Glacial Maximum, with each sinkhole containing peat deposits that date in excess of 21,000 calendar years ago (cal B.P.). These peats are overlain by sandy colluvium that dates to approximately 14,500 cal B.P. The colluvium is overlain by clays that contain evidence for soil formation. These soils vary in age, with radiocarbon dates of approximately 14,500-10,000 cal B.P. These clays are directly overlain by peats dating to 5,000-3,500 cal B.P., which are overlain by peats and clays that date to 2,500-0 cal B.P. Intact Paleoindian and Early Archaic deposits are possible in the late Pleistocene soils.