Variation in Radiocarbon Age Determinations from the Crystal River Archaeological Site, Florida

Radiocarbon ◽  
2014 ◽  
Vol 56 (2) ◽  
pp. 801-810 ◽  
Author(s):  
Alexander Cherkinsky ◽  
Thomas J Pluckhahn ◽  
Victor D Thompson
Keyword(s):  
Gulf Coast ◽  
Archaeological Site ◽  
Bone Collagen ◽  
Shell Midden ◽  
Long Distance ◽  
Reservoir Effect ◽  
Radiocarbon Age ◽  
Soil Charcoal ◽  
Crystal River ◽  
Age Determinations

Archaeologists interested in radiocarbon dating shell midden sites express concern regarding the accuracy of shell dates and how such determinations should be interpreted. This article discusses the problem of dating shells from sites in the southeastern United States. New results are presented comparing shell, bone, and soil-charcoal age determinations from the Crystal River site, located along the west-central Gulf Coast of Florida. Crystal River is a large multimound site whose occupants engaged in long-distance exchange throughout eastern North America during the Woodland period (∼1000 BC to AD 1050). In the summer of 2012, test units were excavated in several contexts at the site, including both mounds and occupation areas. Samples were collected for 14C dating, which were then processed at the University of Georgia Center for Applied Isotope Studies. This article focuses on samples from the stratified shell midden, from which it was hoped to construct a local correction for marine shell that could be used to date other contexts. The soil-charcoal and bone collagen from these samples have very similar ages (bone samples ranging from about 100 cal BC to cal AD 530 and soil-charcoal from cal AD 345 to 560); however, the shell samples collected from the same stratigraphic units are significantly older than the terrestrial dates (ranging from 1300 to 390 cal BC). The difference in calibrated ages between organic materials and the shells ranges between 560 to 1140 yr. This phenomenon cannot be explained solely by the marine reservoir effect. It appears that all the shell samples formed in mixed marine (∼50–60%) contexts, as indicated by the stable isotope ratios and the amount of atmospheric carbon remaining in the samples. The age of the shell samples cannot be used to date archaeological events as they are influenced not only by the marine reservoir effect, but also the local hardwater effect, which makes them significantly older.

Variation in Radiocarbon Age Determinations from the Crystal River Archaeological Site, Florida

Radiocarbon ◽  
2014 ◽  
Vol 56 (02) ◽  
pp. 801-810 ◽  
Author(s):  
Alexander Cherkinsky ◽  
Thomas J Pluckhahn ◽  
Victor D Thompson
Keyword(s):  
Gulf Coast ◽  
Archaeological Site ◽  
Bone Collagen ◽  
Shell Midden ◽  
Long Distance ◽  
Reservoir Effect ◽  
Radiocarbon Age ◽  
Soil Charcoal ◽  
Crystal River ◽  
Age Determinations

Archaeologists interested in radiocarbon dating shell midden sites express concern regarding the accuracy of shell dates and how such determinations should be interpreted. This article discusses the problem of dating shells from sites in the southeastern United States. New results are presented comparing shell, bone, and soil-charcoal age determinations from the Crystal River site, located along the west-central Gulf Coast of Florida. Crystal River is a large multimound site whose occupants engaged in long-distance exchange throughout eastern North America during the Woodland period (∼1000 BC to AD 1050). In the summer of 2012, test units were excavated in several contexts at the site, including both mounds and occupation areas. Samples were collected for14C dating, which were then processed at the University of Georgia Center for Applied Isotope Studies. This article focuses on samples from the stratified shell midden, from which it was hoped to construct a local correction for marine shell that could be used to date other contexts. The soil-charcoal and bone collagen from these samples have very similar ages (bone samples ranging from about 100 cal BC to cal AD 530 and soil-charcoal from cal AD 345 to 560); however, the shell samples collected from the same stratigraphic units are significantly older than the terrestrial dates (ranging from 1300 to 390 cal BC). The difference in calibrated ages between organic materials and the shells ranges between 560 to 1140 yr. This phenomenon cannot be explained solely by the marine reservoir effect. It appears that all the shell samples formed in mixed marine (∼50–60%) contexts, as indicated by the stable isotope ratios and the amount of atmospheric carbon remaining in the samples. The age of the shell samples cannot be used to date archaeological events as they are influenced not only by the marine reservoir effect, but also the local hardwater effect, which makes them significantly older.

scholarly journals Radiocarbon Age Calibration of Marine Samples Back to 9000 Cal Yr BP

Radiocarbon ◽  
1986 ◽  
Vol 28 (2B) ◽  
pp. 980-1021 ◽  
Author(s):  
Minze Stuiver ◽  
G W Pearson ◽  
Tom Braziunas
Keyword(s):  
Special Issue ◽  
Reservoir Effect ◽  
Radiocarbon Age ◽  
Marine Samples ◽  
Calibration Curves ◽  
Age Correction ◽  
The Difference ◽  
Reservoir Age ◽  
Age Determinations

Calibration curves spanning several millennia are now available in this special issue of Radiocarbon. These curves, nearly all derived from the 14C age determinations of wood samples, are to be used for the age conversion of samples that were formed through use of atmospheric CO2. When samples are formed in reservoirs (eg, lakes and oceans) that differ in specific 14C content from the atmosphere, an age adjustment is needed because a conventional 14C age, although taking into account 14C (and 13C) fractionation, does not correct for the difference in specific 14C activity (Stuiver & Polach, 1977). The 14C ages of samples grown in these environments are too old, and a reservoir age correction has to be applied. This phenomenon has been referred to as the reservoir effect (Stuiver & Polach, 1977).

scholarly journals Marine Turtle Bones from an Archaeological Site in Polynesia Yield Reliable Age Determinations

Radiocarbon ◽  
1990 ◽  
Vol 32 (2) ◽  
pp. 143-147 ◽  
Author(s):  
T S Dye
Keyword(s):  
Mass Spectrometry ◽  
Sample Size ◽  
Accelerator Mass Spectrometry ◽  
South Pacific ◽  
Archaeological Site ◽  
Marine Turtle ◽  
Long Distance ◽  
Marine Turtles ◽  
Ams Dating ◽  
Age Determinations

Accelerator mass spectrometry dating of three 50g samples of marine turtle bone from the basal cultural stratum of the Tongoleleka archaeological site, Lifuka Island, Kingdom of Tonga, South Pacific yields results that agree with conventional 14C dates on marine shell. A method for calibrating these dates that takes into account the long distance migrations of marine turtles in the South Pacific is proposed. A sample size greater than 50g is recommended for routine AMS dating of marine turtle bone.

Marine reservoir corrections for bowhead whale radiocarbon age determinations

1996 ◽  
Vol 33 (12) ◽  
pp. 1628-1637 ◽  
Author(s):  
Arthur S. Dyke ◽  
Roger N. McNeely ◽  
James Hooper
Keyword(s):  
Canadian Arctic ◽  
Bowhead Whale ◽  
Bone Collagen ◽  
Radiocarbon Dates ◽  
Marine Molluscs ◽  
Terrestrial Plant ◽  
Radiocarbon Age ◽  
Raised Beaches ◽  
Eastern Canadian Arctic ◽  
Age Determinations

Twenty-two pairs of radiocarbon dates on driftwood and bowhead whale (Balaena mysticetus) bones from raised beaches, dates on whale bone and terrestrial plant detritus from a stratigraphie section, and 25 additional dates on whale bones from the lowest (≤1 ka BP) raised beaches in the eastern Canadian Arctic suggest that a marine reservoir correction of about −200 years is appropriate for normalized age determinations on bone collagen from the bowhead whale in this region. This is less than the correction (−400 years) normally applied to carbonate shells of marine molluscs from this region. The carbon in bowhead collagen appears to be derived from the whales' zooplankton food rather than from marine bicarbonate.

scholarly journals Species-specific reservoir effect estimates: A case study of archaeological marine samples from the Bering Strait

The Holocene ◽  
2021 ◽  
pp. 095968362110417
Author(s):  
Jack PR Dury ◽  
Gunilla Eriksson ◽  
Arkady Savinetsky ◽  
Maria Dobrovolskaya ◽  
Kirill Dneprovsky ◽  
...  
Keyword(s):  
Marine Organism ◽  
Full Range ◽  
Archaeological Site ◽  
Marine Species ◽  
Careful Consideration ◽  
Bone Collagen ◽  
Bering Strait ◽  
Radiocarbon Dates ◽  
Reservoir Effect ◽  
Marine Samples

Due to the marine reservoir effect, radiocarbon dates of marine samples require a correction. Marine reservoir effects, however, may vary among different marine species within a given body of water. Factors such as diet, feeding depth and migratory behaviour all affect the 14C date of a marine organism. Moreover, there is often significant variation within single marine species. Whilst the careful consideration of the Δ R values of a single marine species in a given location is important, so too is the full range of Δ R values within an ecosystem. This paper illustrates this point, using a sample pairing method to estimate the reservoir effects in 17 marine samples, of eight different species, from the archaeological site of Ekven (Eastern Chukotka, Siberia). An OxCal model is used to assess the strength of these estimates. The marine reservoir effects of samples passing the model range from Δ R (Marine20) = 136 ± 41–Δ R = 460 ± 40. Marine reservoir effect estimates of these samples and other published samples are used to explore variability in the wider Bering Strait region. The archaeological implications of this variability are also discussed. The calibrating of 14C dates from human bone collagen, for example, could be improved by applying a dietary relevant marine reservoir effect correction. For humans from the site of Ekven, a Δ R (Marine20) correction of 289 ± 124 years or reservoir age correction of 842 ± 123 years is suggested.

scholarly journals Isotopic Evidence for Long-Distance Connections of the AD Thirteenth-Century Promontory Caves Occupants

2021 ◽  
pp. 1-23
Author(s):  
Jessica Z. Metcalfe ◽  
John W. Ives ◽  
Sabrina Shirazi ◽  
Kevin P. Gilmore ◽  
Jennifer Hallson ◽  
...  
Keyword(s):  
Material Culture ◽  
Thirteenth Century ◽  
Isotopic Analysis ◽  
Bone Collagen ◽  
Turnover Rates ◽  
Long Distance ◽  
Carbon Isotopic ◽  
Local Plant ◽  
Northern Utah ◽  
C Value

The Promontory caves (Utah) and Franktown Cave (Colorado) contain high-fidelity records of short-term occupations by groups with material culture connections to the Subarctic/Northern Plains. This research uses Promontory and Franktown bison dung, hair, hide, and bone collagen to establish local baseline carbon isotopic variability and identify leather from a distant source. The ankle wrap of one Promontory Cave 1 moccasin had a δ13C value that indicates a substantial C4 component to the animal's diet, unlike the C3 diets inferred from 171 other Promontory and northern Utah bison samples. We draw on a unique combination of multitissue isotopic analysis, carbon isoscapes, ancient DNA (species and sex identification), tissue turnover rates, archaeological contexts, and bison ecology to show that the high δ13C value was not likely a result of local plant consumption, bison mobility, or trade. Instead, the bison hide was likely acquired via long-distance travel to/from an area of abundant C4 grasses far to the south or east. Expansive landscape knowledge gained through long-distance associations would have allowed Promontory caves inhabitants to make well-informed decisions about directions and routes of movement for a territorial shift, which seems to have occurred in the late thirteenth century.

scholarly journals C14 dating of Survey material performed in 1974

1975 ◽  
Vol 75 ◽  
pp. 19-20
Author(s):  
A Weidick
Keyword(s):  
New Jersey ◽  
Wood Sample ◽  
Field Work ◽  
Plant Anatomy ◽  
Radiocarbon Age ◽  
Apparent Age ◽  
Age Determinations

Thirteen radiocarbon age determinations of shell samples (12) and wood (1) are assembled in tbis account. The material dated was collected in connection with GGU field work. The samples have been dated at Isotopes Inc., Westwood, New Jersey, U.S.A. Determination of the wood sample was kindly made by Jette Dahl Møller, Institute of Plant Anatomy and Cytology, University of Copenhagen. Dating has also been carried out on a number of shelIs, dredged alive prior to 1950, in order to control the apparent age in shell dating determinations (Tauber & Funder, tbis report).

scholarly journals ARQUEOLOGÍA DE SUPERFICIE EN TAJÍN

2019 ◽  
Vol 34 (2) ◽  
pp. 57
Author(s):  
Pedro Jiménez Lara
Keyword(s):  
Gulf Coast ◽  
Archaeological Site ◽  
Human Scale ◽  
The Law ◽  
Closed Basins ◽  
Great Scope ◽  
Normal Scale

El sitio arqueológico de Tajín es considerado como el más importante de la Costa del Golfo, México, ubicada en una superficie de 144 hectáreas, emplazada en área de pequeñas colinas con cuencas abierta y cerradas, en una sucesión de plazas arquitectónicas edificada en plataformas semi-artificiales de manera estratificada. Edificios con terrazas soportadas por columnas cilíndricas, techos planos de gran envergadura y complejidad. Además de presentar una arquitectura sofisticada a base de lajas que dan forma a los nichos, grecas y cornisa volada, también contiene esculturas en piedra de volumen mediano y figuras a escala humana modeladas en estuco. Presenta 17 juegos de pelota y eso es un indicador de la religiosidad de sus habitantes y sus habituales, representaciones del ritual plasmado en 6 tableros usando la técnica de bajorelieves. Aquí, también, encontramos pinturas a escala normal y en miniatura. Es inconmensurable la riqueza iconográfica que marcan los hechos más relevantes de sus gobernantes.SURFACE ARCHEOLOGY IN TAJÍN ABSTRACTThe archaeological site of Tajín is considered as the most important of the Gulf Coast, Mexico, located in an area of 144 hectares, located in an area of small hills with open and closed basins, in a succession of architectural squares built on semiartificial platforms of stratified way. Buildings with terraces supported by cylindrical columns, planes of great scope and complexity. In addition to presenting a sophisticated architecture, a basis of the law that shapes the niches, fretwork and flown cornice, it also contains stone sculptures of medical volume and figures in a human scale modeled in stucco. It presents 17 ball games and that is an indicator of the religiosity of its inhabitants and their regulars, representations of the ritual embodied in 6 paintings using the technique of bas-reliefs. Here, too, we find paintings on a normal scale and in miniature. The iconographic wealth that marks the most relevant events of its rulers is immeasurable.Key words: Archeology, Tajín, Complexity, Painting, Iconography

From Regional Center to Mound-Residential Compound (Phase 3)

2018 ◽  
pp. 155-167
Author(s):  
Thomas J. Pluckhahn ◽  
Victor D. Thompson
Keyword(s):  
Gulf Coast ◽  
Late Woodland ◽  
Phase 3 ◽  
Her Family ◽  
Late Woodland Period ◽  
Regional Center ◽  
Archaeological Work ◽  
Crystal River ◽  
Area North ◽  
The Village

Recent archaeological work suggests that people began moving away from Crystal River in Phase 3, which probably began between around AD 500 and 600 and lasted until sometime between AD 650 and 750, during the Late Woodland Period. Nevertheless, the site seems to have continued to serve as a ceremonial center. The village contracted to the area north of Mound A, which was expanded during this interval; perhaps the continuing presence represents a caretaker population or a compound occupied by a leader and his or her family. Some of the former residents of Crystal River may have moved the short distance downstream to Roberts Island, where settlement was initiated in this interval. Shifts in settlement such as this abandonment and collapse are typical of the Gulf Coast at this time, and may be at least in part a response to a more variable climate and lowered sea level associated with the interval known as the Vandal Minimum.

From Early Village to Regional Center (Phase 2)

2018 ◽  
pp. 117-154
Author(s):  
Thomas J. Pluckhahn ◽  
Victor D. Thompson
Keyword(s):  
Sea Level ◽  
Gulf Coast ◽  
Warm Period ◽  
Phase 2 ◽  
Regional Center ◽  
Crystal River ◽  
Southern Florida ◽  
The Village ◽  
Weeden Island ◽  
Small Platform

The village at Crystal River expanded greatly in size and permanence in Phase 2, which began sometime between around AD 200 and 300 and ended by around AD 500. This growth may have owed partially to a rise in sea level associated with the warmer temperatures of the Roman Warm Period, which might have made life on the seaward islands more difficult. The exchange of Hopewell exotics faded in this interval, but the societies of the Gulf Coast appear to have witnessed a fluorescence, as indicated by the widespread exchange of Swift Creek pottery and Weeden Island pottery. Crystal River was peripheral to these pottery traditions, but it may have been an important nexus between these and the Glades tradition of southern Florida, specifically with regard to the exchange of craft goods manufactured from marine shell. The gulf coast fluorescence is also indicated by a heightened pace of the construction of mounds. At Crystal River, three small platform mounds were initiated in this interval, clearly differentiating it from its peers in the region.

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