The Ryan/Harley site: Sedimentology of an inundated Paleoindian site in north Florida

Abstract

The Ryan/Harley site (Florida Master Site File Number: 8Je-1004) is a Middle Paleoindian habitation site containing Suwannee points. Based on stratigraphic correlation and diagnostic artifact seriation, Suwannee-age sites have been relatively dated from ~10,900 14 C yr B.P. to ~10,500 14 C yr B.P. Clovis-like traits on the Suwannee points and other stone tools from the Ryan/Harley site suggest it dates to the earlier end of the Suwannee timeframe. The currently inundated site is partially buried beneath a sediment column located in a swamp forest and partially exposed in a side channel section of the Wacissa River, Jefferson County, Florida. Research done prior to this analysis determined that the artifact assemblage appeared to be unsorted and was contained in a midden-like unit. Our purpose here is to assess the issue of site integrity further. Unconsolidated sediment samples collected from the artifact-bearing horizon and from horizons immediately above and below the artifact horizon were analyzed using granulometric techniques. Arithmetic probability plots of the grain-size distributions show that the sediments were transported and deposited by fluvial processes. Thus, the Suwannee points and associated artifacts, and faunal remains appear to have accumulated during a time of subaerial exposure perhaps after a regional water-table decline, and have remained largely or essentially intact, with little or no postdepositional reworking. The artifacts and faunal remains recovered from the artifact-bearing horizon at Ryan/Harley are distributed randomly, showing no sign of sorting. In the fossil suite, two articulated white-tailed deer (Odocoileus virginianus) vertebra were recovered in situ. The unsorted nature of artifacts and articulated faunal remains that are contained within the fluvially deposited sediments suggests the Suwannee point level of the Ryan/Harley site has remained undisturbed since original deposition.

Geoarchaeological investigations at the Ryan‐Harley Paleoindian site, Florida (8JE1004): Implications for human settlement of the Wacissa River Basin during the Younger Dryas

“…The preponderance of evidence indicates that eolian activity shaped the relict interglacial deposits of marine sands in the Wacissa River Basin before, during, and shortly after the Late Pleistocene human occupation of Ryan‐Harley, as seen elsewhere on the Gulf of Mexico and Atlantic Coastal Plain. This contradicts the previously published geologic results from Ryan‐Harley, which proposed fluvial deposition as the main agent for units 2 and 3, although the authors do note that eolian signatures are present in their data (Balsillie et al, 2006). This determination was likely a result of the Gaussian analyses used during the previous study, which assume a roughly normal distribution of sediment sizes; a condition not met by eolian sediments, which are inherently skewed toward fine clasts.…”

“…Ryan‐Harley contains six stratigraphic units (Figure 2; Balsillie et al, 2006). The stratigraphy described here is based on field observations from profiles exposed in 2015 and 2017, four ground‐penetrating transects and six cores.…”

“…Dunbar et al (2006) excavated 193 lithic artifacts and 368 faunal specimens from ~5 m 2 of this stratum, which was actively eroding. Texture analyses determined that the sediments containing the artifacts likely derived from fluvial activity, but eolian signatures are also noted (Balsillie, Means, & Dunbar, 2006). In 2015, the author excavated 12 m 2 of the archaeological component, recovering 889 lithic artifacts and 1763 faunal elements.…”

“…Further excavations in 2017 found 174 lithic artifacts and 241 faunal items within a 3 m 2 area. Previous excavators proposed that Ryan‐Harley represents an ephemeral encampment along a riverbank or levee (Balsillie et al, 2006; Dunbar et al, 2006). The archaeological assemblage from Ryan‐Harley contains debitage as well as unifacial and bifacial stone tools, including Suwannee points.…”

Geoarchaeological framework of Late Pleistocene and Early Holocene sites in the Aucilla River Basin, Northwest Florida, USA

“…Ryan Harley, located within a stream bank in the braided Wacissa River, contains a Suwannee component on top of a paleosol (Balsillie et al, 2006; Smith, 2020). This northernmost site is the only one located within the clear waters of the Wacissa River and the only not within a sinkhole.…”