Issues in Building Radiocarbon Chronologies

DOCUMENT Citation Only David Wright.

Primarily located in the tropical latitudes with a diverse array of unique floral and fauna, there are unique challenges for obtaining a reliable chronology for archaeological sites on the African subcontinent. Radiocarbon dating is the most frequently employed method for gaining age control on Late Quaternary sites, however aspects affecting the accuracy of the method are rarely considered. Carbon recycling from reservoirs in old sedimentary structures may uptake into ostrich eggshell or...

DOCUMENT Citation Only Steven Forman.

OSL dating has advanced in the past decade with refinements in single aliquot and single grain regeneration (SAR) dating of quartz and feldspar. There is now many independent studies to evaluate the accuracy and precision of OSL dating, particularly for eolian and littoral sediments where solar resetting is often assured. This assessment will examine the potential meaning of radiocarbon ages that are > 45 ka in light of corresponding finite OSL ages for fluvial and marine sediments from the...

DOCUMENT Citation Only Jaeyong Lee. Youngseon Lee. Jangsuk Kim.

The goal of the study is to investigate the uncertainty of radiocarbon dating measurements. To study the variability of the measurements, the samples from the same specimen were sent to different radiocarbon dating labs and the estimated dates from various labs were obtained as data for analysis. Through a Baeysian analysis of the data, we could estimate the variability of the labs as well as variability between labs. SAA 2015 abstracts made available in tDAR courtesy of the Society for...

DOCUMENT Citation Only Michael Waters.

Chronology is key to understanding the story of the first Americans. Accurate and precise ages from sites are necessary to develop chronological relationships and overlaps among different Paleoindian complexes. Proper dating of any Paleoindian horizon requires an understanding of the geological context, geochemical environment and potential contamination factors, material and chemical fraction dated, number of ages obtained, and many other variables. Without understanding these factors of...

DOCUMENT Citation Only Kenneth Ames. Andrew Martindale. Kevan Edinborough. Kisha Supernent. Bryn Letham.

A large regional suite of radiocarbon dates documents changing Pacific Period settlement patterns in the Prince Rupert Harbor region of northern British Columbia. Late Pleistocene/Holocene sea level changes focuses discussion on the last 5000 years. At that time, the settlement pattern appears to be one of small, one to four house communities dispersed across the sea-scape. Non-residential middens are present throughout the Holocene. Larger linear villages appear after 5000 calBP and larger...

DOCUMENT Citation Only Jangsuk Kim.

Using the number of uncalibrated BP dates or summed probabilistic density of calibrated dates, many studies attempt to monitor demographic dynamics of the past. However, some practical factors including differences in intensity and density of archaeological investigations and the preservation of datable materials, natural decay, and even different financial situations of investigations can cause sampling biases, eventually leading to distorted distributions of radiocarbon dates. Thus, database...

DOCUMENT Citation Only Kenichi Yano.

This paper surveys our recent studies on fluctuation in prehistoric population of each local area in Jomon or Japanese neolithic period, and infers the reasons for the fluctuations in archaeological contexts. Archaeological demographic reconstruction in Japan has been based on numbers of archaeological sites or structures such as pit dwellings. In Japanese archaeology, pottery chronology has been established in detail. In recent years, many 14C data of various pottery types in Jomon period...

DOCUMENT Citation Only Thomas Brown. Kevan Edinborough. Kenneth Ames.

Using data from a newly constructed regional 14C database for the Early and Middle-Holocene on the northern Northwest Coast of North America, a combination of Bayesian models, summed probability distributions and spatial analyses are used to evaluate hypotheses regarding the nature and timing for the development of collector strategies on the northern coast. Research and taphonomic biases are accounted for by binning the radiocarbon data, and by applying a general linear model to the data set. I...

DOCUMENT Citation Only Colin Grier. Eric McLay. Michael Richards.

Shell and other marine-derived materials are common in Northwest Coast archaeological sites, particularly shell middens. Yet, uncertainties in the marine reservoir offset have produced a hesitation among some researchers to generate or utilize chronological information derived from marine samples. Clearly. marine-derived dates introduce significant complexities into chronology building that need to be addressed. Here, we present radiocarbon results generated through dating two or three samples...

DOCUMENT Citation Only Chuntaek Seong. Jae Hoon Hwang.

The present study attempts to reconsider the late Neolithic and early Bronze Age transition in central Korea based on evaluation of available radiocarbon dates. Issues regarding reliability of the radiometric dating and its implications on the reconstruction of occupational density are addressed along with methods of evaluating a large set of radiocarbon dates falling between 2000 BC and 1000 BC. This in turn provides a basis for testing common assumptions of the transitional period in Korea....

DOCUMENT Citation Only Kevan Edinborough.

The initial results of a radiocarbon local marine reservoir correction study are presented for Prince Rupert Harbor in northern British Columbia, Canada. These preliminary results are integrated into a series of Bayesian age-depth models that illustrate how shell-midden accumulation rates can dramatically vary. Village development in the harbor is discussed in the light of these new findings. SAA 2015 abstracts made available in tDAR courtesy of the Society for American Archaeology and Center...

DOCUMENT Citation Only Jaehoon Hwang. Chuntaek Seong. Jaeyong Lee. Jangsuk Kim. Seonho Choi.

Radiocarbon dating in the modern age is a precise experiment requiring an understanding of nuclear physics using accelerators It require measurements on the order of parts per trillion of carbon 14 nuclei in samples. Although most of the procedures of radiocarbon dating are standardized these days, the final results of the measurements have limitations on precision and accuracy that require careful verification before final acceptance. Recently, our group has carried out radiocarbon dating on...

DOCUMENT Citation Only Patrick Dolan. Colin Grier.

Documenting the formation, growth, and decline of individual settlements is critical to explaining the development of settled village life. Radiocarbon dating is often the best, and in our case only, chronometric tool for establishing these temporal dynamics. Here, we explore several approaches to reconstructing the temporality of settlement at the Dionisio Point site, a precontact plankhouse village in southwestern British Columbia. Two decades of research at this 1,500 year-old...

DOCUMENT Citation Only Andrew Martindale. Matthew Betts. Michael Blake. Nicholas Jakobsen. Ryan Wallace.

CARD was developed at the Canadian Museum of Civilization (now the Canadian Museum of History) by Richard Morlan as a text-based online tool to compile c14 dates from archaeological and palaeontological contexts. Over the years it has compiled about 40,000 dates from across Canada and into the northern United States. The database has grown to the extent that it can now be used to answer critical continental-scale questions of demography and human-ecosystem interactions In July 2014, the CMH and...

DOCUMENT Citation Only David Thulman.

Many archaeologists struggle to make sense of radiocarbon dates, especially those with large overlapping sigmas. Even with modern analytical techniques that increase precision, the results can be confusing. Bayesian statistics, which employs prior information to constrain posterior results with sets of radiocarbon dates, can lessen confusion and increase precision without using ad hoc measures, such as averaging or ignoring dates with large errors. The power and utility of Bayesian analyses is...