A dating intercomparison study on Late Stone Age coastal midden deposits, South Africa

Abstract

The southern and western coastlines of South Africa have an extensive archaeological record with many sites associated with widespread eolian deposits. While much of this rich archaeological record is based on cave sites, evidence of Late Stone Age occupation is additionally preserved in the form of open-site shell middens. We present here a comparative study of the application of amino acid racemization (AAR), optically stimulated luminescence (OSL), and radiocarbon analyses to three Late Stone Age (LSA) midden sites found within dunes on the southern coastline of South Africa. Preliminary geochronological analyses suggest that middens offer opportunity to fill in gaps in what is still a fragmentary archaeological record. Results show OSL and radiocarbon ages in good agreement, illustrating the potential to date not only the middens but also the surrounding dunes that constituted the dwelling sites. AAR results show increasing ratios with age and also that the application of paired shell and "whole rock" AAR can provide insights into the degree of biogenic sediment recycling at buried midden sites. However, the work also highlights that caution is required when OSL sampling sediment associated with middens which may have undergone human disturbance and that further work is required to improve the regional marine reservoir correction for radiocarbon dating in this part of South Africa. The study also illustrates that AAR will only provide useful data provided that middens have been sufficiently deeply buried to overcome fluctuations in environmental variables that affect the racemization rate and that inter-genus comparisons should be avoided. © 2008 Wiley Periodicals, Inc. INTRODUCTIONThe South African coastline exhibits an extensive suite of Holocene coastal dunes, the most recent manifestation of multiple generations of eolianites ranging in age back to the Neogene (Illenberger, 1996;Roberts & Brink, 2002;Bateman et al., 2004). Geoarchaeology: An International Journal, Vol. 23, No. 6, 715-741 (2008 Coastal dunefields of the southern coast are commonly found within logspiral bays on the down-drift aspect of river mouths. Some localities such as Sedgefield exhibit multiple accretionary dune complexes that in places exceed 30 m in height (e.g., Tinley, 1985;Illenberger, 1996;Roberts & Brink, 2002;Bateman et al., 2004). Renowned archaeological cave sites, including Die Kelders, Blombos, Pinnacle Point, and the Klasies River mouth are also found along this coastline and contain evidence for the emergence of early anatomically and cognitively modern humans during the Middle Stone Age (MSA; ca. 250-12 ka; e.g., Henshilwood et al., 2002Henshilwood et al., , 2004Marean et al., 2007). Deposits within the caves are frequently of eolian origin and may contain or have influenced the preservation of archaeological material (Henshilwood et al., 2004;Marean et al., 2007). These sites record the human occupation and subsistence in the coastal zone as far back as marine isotope stage 6 or ca. 160 ka (Marean et al., 2007). Evide...

Shell Middens, Cultural Chronologies, and Coastal Settlement on the Rhode River Sub‐Estuary of Chesapeake Bay, Maryland, USA

“…Our study complements recent radiocarbon studies by coastal archaeologists in other regions. From the San Juan Islands of the Pacific Northwest (Taylor et al., ) to St. Catherine's Island, Georgia (Thomas, , Thomas et al., ), the southern Curtis Coast of Queensland, Australia (see Ulm, ), the South African Coast (Bateman et al., ; Jerardino, ), coastal Pakistan (Biagi et al., ), the California Channel Islands (Erlandson et al., ), and beyond these studies are a crucial step in understanding past coastal lifeways and settlement strategies and helping define more targeted future research. Despite the growing trend, additional research is needed in other coastal areas as we continue to race against the effects of sea‐level rise and marine erosion.…”

Sediment provenance of the Wilderness barrier dunes, southern Cape coast, South Africa

“…, 2007). Samples from the crest of the barrier are of Holocene age (Table 1) (Bateman et al. , 2008; Carr et al.…”

Stratigraphic and spatial variability in shell middens: microfacies identification at the ethnohistoric site Tunel VII (Tierra del Fuego, Argentina)

“…Geoarchaeological research on shell middens has mostly focused on two subjects: environmental reconstructions based on shell assemblages, used as indicators of past climatic conditions, and the relationship between sedimentary evolution and human occupation of coastal settings, based on the definition of sea-level fluctuations (see Bateman et al 2008;Butzer 2004;Cannon 2000;Compton and Franceschini 2005;Cortez-Sanchez et al 2008;Erlandson et al 2005;Fedje and Christensen 1999;Morey and Crothers 1998;Whittaker and Stein 1992, among others). Research has also been done to distinguish anthropogenic from natural shell deposits (Henderson et al 2002;Rosendahl et al 2007) and to understand archaeological stratigraphies and site formation processes (Morey et al 2002;Stein 1992aStein , b, c, 1996Stein et al 1992;Vila et al 2010).…”