• Radiocarbon and Dendrochronological Dates of the Corded Ware Culture

      Włodarczak, Piotr (Department of Geosciences, The University of Arizona, 2009-01-01)
      This paper presents and discusses radiocarbon dates of the Corded Ware culture (CWC) from different regions of Europe (mainly from southern and central Germany and southern and central Poland). The main questions addressed are the controversial significance of particular results, the incompatibility of the obtained date sequences, and the "imprecision of the method." There is clearly the problem of hundreds of dates from different laboratories and performed in different years. A slight difference in the results leads to an "elongated"chronology and acceptance of a model with synchronicity of many cultural groups. The proposed verification of the 14C chronology is connected with both the dendrochronological method and the comparison of dating sequences obtained from particular regions. At present, the most reliable dating scheme for the Corded Ware culture is the one based on the dendrochronological dates of settlements on Swiss lakes; therefore, the scheme must constitute a reference point for 14C analyses conducted for other regions. Due to the typological diversity of materials, however, not every situation allows for this approach. Thus, many 14C grave dates, particularly the results referring to the late CWC phase (after ~2400 BC), remain controversial.
    • Radiocarbon Dates and the Earliest Colonization of East Polynesia: More than a Case Study

      Della Casa, Philippe (Department of Geosciences, The University of Arizona, 2009-01-01)
      Over the last 30 yr, there has been an ongoing debate on the dates and modes of the earliest colonization of East Polynesia, namely the Cook Islands, the 5 archipelagos of French Polynesia, the Hawai'i Islands, Easter Island, and New Zealand. At least 3 alternative models were proposed by Sinoto, Anderson, Kirch, and Conte, but interestingly all these models basically relied on the same set of roughly 200 radiocarbon dates on various organic materials from archaeological excavations as far back as the 1950s. Some of the models differed by 500-1000 yr--for a proposed initial colonization around the turn of the BC/AD eras, if not considerably later. By comparing the different approaches to this chronological issue, it becomes evident that almost all known problems in dealing with 14C dates from archaeological excavations are involved: stratigraphy and exact location of samples, sample material and quality, inbuilt ages and reservoir effects, lab errors in ancient dates, etc. More recently, research into landscape and vegetation history has produced alternative 14C dating for early human impact, adding to the confusion about the initial stages of island colonization, while archaeological 14C dates, becoming increasingly "young" as compared to former investigations, now advocate a rapid and late (post-AD 900) colonization of the archipelagos. As it appears, the Polynesian case is more than just another case study, it's a lesson on 14C-based archaeological chronology. The present paper does not pretend to solve the problems of early Polynesian colonization, but intends to contribute to the debate on how 14C specialists and archaeologists might cooperate in the future.
    • Radiocarbon Dating of Calcined Bones: Where Does the Carbon Come from?

      Zazzo, A.; Saliège, J-F.; Person, A.; Boucher, H. (Department of Geosciences, The University of Arizona, 2009-01-01)
      Over the past decade, radiocarbon dating of the carbonate contained in the mineral fraction of calcined bones has emerged as a viable alternative to dating skeletal remains in situations where collagen is no longer present. However, anomalously low 13C values have been reported for calcined bones, suggesting that the mineral fraction of bone is altered. Therefore, exchange with other sources of carbon during heating cannot be excluded. Here, we report new results from analyses on cremated bones found in archaeological sites in Africa and the Near East, as well as the results of several experiments aiming at improving our understanding of the fate of mineral and organic carbon of bone during heating. Heating of modern bone was carried out at different temperatures, for different durations, and under natural and controlled conditions, and the evolution of several parameters (weight, color, %C, %N, 13C value, carbonate content, crystallinity indexes measured by XRD and FTIR) was monitored. Results from archaeological sites confirm that calcined bones are unreliable for paleoenvironmental and paleodietary reconstruction using stable isotopes. Experimental results suggest that the carbon remaining in bone after cremation likely comes from the original inorganic pool, highly fractionated due to rapid recrystallization. Therefore, its reliability for 14C dating should be seen as close to that of tooth enamel, due to crystallographic properties of calcined bones.
    • Radiocarbon Dating of Iron: A Northern Contribution

      Oinonen, M.; Haggren, G.; Kaskela, A.; Lavento, M.; Palonen, V.; Tikkanen, P. (Department of Geosciences, The University of Arizona, 2009-01-01)
      The iron dating project Aikarauta has been launched in Finland. This paper presents the results of the preliminary investigations. The ability for radiocarbon measurement by accelerator mass spectrometry (AMS) of iron in Finland has been demonstrated by using coal-produced iron as reference material. An elemental analyzer has been harnessed to measure the carbon content of small iron samples. In addition, we have hypothesized that a fingerprint of the limestone usage in the smelting process is the high Ca content of iron and slag. This has been examined by performing an iron smelting experiment with limestone as flux, by making elemental analyses of ingredients and the resulting slag and iron, and by a 14C analysis of the produced iron. It is possible that limestone dilutes the 14C contents of the produced iron, making its age determination challenging.
    • Radiocarbon Dating of Lumps from Aerial Lime Mortars and Plasters: Methodological Issues and Results from San Nicolò of Capodimonte Church (Camogli, Genoa, Italy)

      Pesce, G.; Quarta, G.; Calcagnile, L.; D'Elia, M.; Cavaciocchi, P.; Lastrico, C.; Guastella, R. (Department of Geosciences, The University of Arizona, 2009-01-01)
      This paper deals with the potentialities and technical and methodological issues associated with the use of lumps of not completely melted lime as material suitable for the radiocarbon dating of aerial lime mortars and plasters. In fact, the identification and selection of single aggregates of unmelted lumps allows one to reduce the possible contamination resulting from external sources of carbon such as "14C-dead" limestone in sand added to the mixture during preparation. This procedure results in the possibility for accurate 14C determinations from single pieces of masonry, supplying important information about the construction phases of historical buildings. The potential of this approach is shown by presenting the results of the archaeological study on the walls of San Nicol of Capodimonte church (Camogli, Genoa, Italy), where this technique has been successfully applied to obtain absolute ages of different parts of the building. The obtained results were then compared with the information gathered from historical sources and with stratigraphic and other archaeological studies.
    • Radiocarbon Dating of Neolithic Pottery

      Zaitseva, G.; Skripkin, V.; Kovaliukh, N.; Possnert, G.; Dolukhanov, P.; Vybornov, A. (Department of Geosciences, The University of Arizona, 2009-01-01)
      The direct measurement of organic matter included in archaeological pottery may yield a reliable assessment of age. The main problem consists in the identification of possible origins and assessment of distortion for the age of organic inclusions. Our experiments show that shells included in pottery fabrics are strongly influenced by the reservoir effect, which may reach 500 yr or more. Other organic inclusions, such as lake ooze, do not visibly distort the age. The obtained series of radiocarbon dates have been used for the assessing the age of the early stages of pottery manufacture in southern Russia.
    • Radiocarbon Dating of the Western European Neolithic: Comparison of the Dates on Bones and Dates on Charcoals

      Denaire, Anthony (Department of Geosciences, The University of Arizona, 2009-01-01)
      The subject of this article is the radiocarbon dating on bones in the western European Neolithic. By gathering 14C dates for 2 examples, one chosen in the middle Neolithic of the Rhine region and the other in the end of the early Neolithic in the same region and in the Paris Basin, a significant gap appears between the sum probabilities of dates on charcoals and the ones obtained with bones. A comparison between these results with the few available dendrochronological dates shows that dates on bones seem too young, while the sequence based on charcoals fits. The existence of too-young 14C dates of bones is not new: this phenomenon was already indicated in previous studies. Most explanations agree that there was a source of contamination, during the sample's burial or its treatment in laboratory. These examples illustrate that consequences can be heavy on a chronology built, partly or entirely, on 14C dates of bones..
    • Radiocarbon Measurement Program at the Centro Nacional de Aceleradores (CNA), Spain

      Santos Arévalo, F. Javier; Gómez Martínez, Isabel; García León, Manuel (Department of Geosciences, The University of Arizona, 2009-01-01)
      In September 2005, an accelerator mass spectrometry (AMS) system based on a 1MV Tandetron accelerator arrived at the Centro Nacional de Aceleradores (CNA). One of the main research programs for this AMS facility is based on radiocarbon. At the same time as the AMS facility was installed and tested, the 14C sample preparation laboratory was designed and set up. A graphitization line that allows the preparation of 5 samples in parallel was designed and built in October 2006. The first months were mainly dedicated to check and optimize all the sample processing. For such a task, several reference samples have been prepared and measured. Since the beginning of 2007, the laboratory has been fully operational and is currently performing as a service for the scientific community. During 2007, nearly 100 unknown samples were prepared and measured in our AMS system. Most of them were for dating purposes, but also other applications were investigated. The performance of the 14C laboratory and dating service will be shown, with some examples as illustration.
    • Systematic Bias of Radiocarbon Method

      Walanus, Adam (Department of Geosciences, The University of Arizona, 2009-01-01)
      Systematic bias of dates can became statistically significant regarding the growing global number of dates connected with the calibration curve plateau. For example, samples of true age in the span 800-700 BC are dated to be roughly 100 younger, on average. The curve of expected bias for a given age is presented. To avoid such a bias, the Bayesian paradigm probably must be modified in some way.
    • Table of Contents

      Department of Geosciences, The University of Arizona, 2009-01-01
    • Temporal Change of Radiocarbon Reservoir Effect in Sugan Lake, Northwest China during the Late Holocene

      Zhou, Ai-feng; Chen, Fa-hu; Wang, Zong-li; Yang, Mei-lin; Qiang, Ming-rui; Zhang, Jia-wu (Department of Geosciences, The University of Arizona, 2009-01-01)
      Many lacustrine chronology records suffer from radiocarbon reservoir effects. A continuous, accurate varve chronology, in conjunction with accelerator mass spectrometry (AMS) 14C dating, was used to determine the age of lacustrine sediment and to quantify the past 14C reservoir effect in Sugan Lake (China). Reservoir age varied from 4340 to 2590 yr due to 14C-depleted water in the late Holocene. However, during the Little Ice Age (LIA), 14C reservoir age was relatively stable. According to this study, 14C reservoir age in the late Holocene may be driven by hydrological and climatic changes of this period. Therefore, special caution should be paid to the correction of the 14C reservoir effect by a unique 14C reservoir age in paleoclimatic and paleolimnological study of northwest China.
    • The Formation of Deluvial and Alluvial Cones as a Consequence of Human Settlement on a Loess Plateau: An Example from the Chroberz Area (Poland)

      Szwarczewski, Piotr (Department of Geosciences, The University of Arizona, 2009-01-01)
      The area of Chroberz (southern Poland) poses questions of an interdisciplinary character comprising geomorphologic, sedimentation, and archaeological-historical problems. The main aim of this study was to identify the geomorphologic response to changes in the natural environment that took place in the area of the loess plateau (and its close vicinity) as a result of its settlement by man and of climate change. Periods of particularly intense human activity (land-use changes, deforestation, and agriculture) were recorded as changes in the type of sedimentation, i.e. organic sedimentation substituted for mineral one; it was extremely intensive during the Neolithic Age, Iron Age, and Early Middle Ages. The conducted fieldwork research, analysis of available archaeological materials, and radiocarbon dating results show that there is a direct connection between human economic activity in primeval and historic times and between soil erosion and accumulation of colluvial/alluvial fans in the surroundings of the locality of Chroberz. 14C dates documenting the age of colluvial sediment formation show that individual areas of the upland were settled by humans asynchronously. On the basis of a low facial variability, or, occasionally, even homogeneity, of individual colluvia (from soil erosion) and their considerable thickness, it can be concluded that the land was in constant use or that the intervals with no human activity were relatively short. The progressing human impact process is visible both in the form progradation recorded as the changes in 14C ages (e.g. from 1440 +/- 100 to 780 +/- 80 BP) and in textural (e.g. chemical) features of sediments of which the examined fans are composed.
    • The Impact of Cremated Bone Dating on the Archaeological Chronology of the Low Countries

      De Mulder, Guy; Van Strydonck, Mark; Boudin, Mathieu (Department of Geosciences, The University of Arizona, 2009-01-01)
      Since the publication of the first article (Lanting and van der Plicht 2001/2002) about the possibilities of dating cremated bones, the number of dated cremation remains has grown exponentially. The success of this dating technique lies in the fact that an absolute date now can be attributed to archaeological phenomena that previously were only datable indirectly. When archaeological artifacts where present, the cremation burials were dated based on the typology of ceramics and metals. An absolute date could be attributed if charcoal from the pyre were present. Unfortunately, these items were not omnipresent at the burial sites. Consequently, a complete site was dated by means of the few datable burials present. This implies that the internal chronology of the site could not be studied. Furthermore, the typochronology of the ceramics and the metals remains questionable. A series of dating projects on urnfield cemeteries in the Low Countries (northern France, Belgium, and the Netherlands) have shown that the classical chronology of these sites must be revised.
    • The Minoan Santorini Eruption and Tsunami Deposits in Palaikastro (Crete): Dating by Geology, Archaeology, 14C, and Egyptian Chronology

      Bruins, Hendrik J.; van der Plicht, Johannes; MacGillivray, J. Alexander (Department of Geosciences, The University of Arizona, 2009-01-01)
      Deposits from the Minoan Santorini (Thera) eruption in the eastern Mediterranean region constitute the most important regional stratigraphic marker in the chronological perplexity of the 2nd millennium BCE. Extensive tsunami deposits were discovered in Crete at the Minoan archaeological site of Palaikastro, containing reworked volcanic Santorini ash. Hence, airborne deposition of volcanic ash, probably during the 1st (Plinian) eruption phase, preceded the tsunami, which was apparently generated during the 3rd or 4th phase of the eruption, based on evidence from Thera. Average radiocarbon dates (uncalibrated) of animal bones in the Palaikastro tsunami deposits along the coast (3350 +/- 25 BP) and at the inland archaeological site (3352 +/- 23 BP) are astoundingly similar to the average 14C date for the Minoan Santorini eruption at Akrotiri on Thera (3350 +/- 10 BP). The wiggle-matched 14C date of the eruption in calendar years is 1627-1600 cal BCE. Late Minoan IA pottery is the youngest element in the Palaikastro tsunami deposits, fitting with the LM IA archaeological date for the Santorini eruption, conventionally linked at ~1500 BCE with Dynasty XVIII of the historical Egyptian chronology. The reasons for the discrepancy of 100-150 yr between 14C dating and Egyptian chronology for part of the 2nd millennium BCE are unknown. 14C dates from Tell el-Dabca in the eastern Nile Delta show that the 14C age of the Santorini eruption matches with 14C results from 18th Dynasty strata C3 and C2, thereby confirming grosso modo the conventional archaeo-historical correlations between the Aegean and Egypt. We propose that a dual dating system is used in parallel: (1) archaeological material-cultural correlations linked to Egyptian chronology; (2) 14C dating. Mixing of dates from the 2 systems may lead to erroneous archaeological and historical correlations. A 'calibration curve' should be established between Egyptian chronology and 14C dating for the 2nd millennium BCE, which may also assist to resolve the cause of the discrepancy.
    • The Spread of the Neolithic in the South East European Plain: Radiocarbon Chronology, Subsistence, and Environment

      Dolukhanov, Pavel M.; Shukurov, Anvar; Davison, Kate; Sarson, Graeme; Gerasimenko, Natalia P.; Pashkevich, Galina A.; Vybornov, Aleksandr A.; Kovalyukh, Vikolai N.; Skripkin, V. V.; Zaitseva, Ganna I.; et al. (Department of Geosciences, The University of Arizona, 2009-01-01)
      Newly available radiocarbon dates show the early signs of pottery-making in the North Caspian area, the Middle-Lower Volga, and the Lower Don at 8-7 kyr cal BC. Stable settlements, as indicated by "coeval subsamples," are recognized in the Middle-Lower Volga (Yelshanian) at 6.8 kyr cal BC and the Caspian Lowland at about 6 kyr cal BC. The ages of the Strumel-Gostyatin, Surskian, and Bug-Dniesterian sites are in the range of 6.6-4.5 kyr BC, overlapping with early farming entities (Starčevo-Krs-Criş and Linear Pottery), whose influence is perceptible in archaeological materials. Likewise, the 14C-dated pollen data show that the spread of early pottery-making coincided with increased precipitation throughout the forest-steppe area.
    • Ultrafiltration: Boon or Bane?

      Hüls, C. M.; Grootes, P. M.; Nadeau, M.-J. (Department of Geosciences, The University of Arizona, 2009-01-01)
      Ultrafiltration of bone collagen, dissolved as gelatin (M ~100,000 D), has received considerable attention as a means to remove small contaminants and thus produce more reliable dates (Brown et al. 1988; Bronk Ramsey et al. 2004; Higham et al. 2006; Mellars 2006). However, comparative dating studies have raised the question whether this cleaning step itself may introduce contamination with carbon from the filters used (Bronk Ramsey et al. 2004; Brock et al. 2007; Hüls et al. 2007). Here, we present results of further ultrafiltration experiments with modern and fossil collagen samples using Vivaspin 20 and Vivaspin 15R ultrafilters. Evidently, the Vivaspin 20 (VS 20) ultrafilter with a polyethersulfone (PES) membrane retains more material in the 30 kD fraction than the Vivaspin 15R (VS 15R) filter with a regenerated cellulose membrane (Hydrosat), which may be related to increased retention of proteins due to suboptimal electrostatic conditions during ultrafiltration with the PES membrane. In addition, this filter type shows clear evidence for contamination with fossil carbon, presumably from membrane fibers, in the 30 kD fraction. Radiocarbon measurements on ultrafiltrated fossil collagen seem to indicate small contributions of modern carbon via glycerin left on and within the filter membranes of both types. Although SEM pictures show film remnants on the fibrous filter structure of cleaned filter membranes, EDX analysis on the VS 20 membrane to not support the assumption this may be glycerin. Our observations indicate the risks and benefits of the use of ultrafiltration in cleaning collagen samples for 14C dating need to be further quantified, especially for the cleaning of fossil bone collagen of good quality samples.
    • Wiggle-Matching Using Known-Age Pine from Jermyn Street, London

      Tyers, Cathy; Sidell, Jane; van der Plicht, Johannes; Marshall, Peter; Cook, Gordon; Bronk Ramsey, Christopher; Bayliss, Alex (Department of Geosciences, The University of Arizona, 2009-01-01)
      A slice of pine from the period covered by single-year calibration data (Stuiver 1993) was selected to serve as part of the quality assurance procedures of the English Heritage radiocarbon dating program, following successful wiggle-matching of 14C measurements from structural 15th century English oak timbers (Hamilton et al. 2007). The timber selected was a roofing element from a house on Jermyn Street, central London, demonstrated by dendrochronology to have been felled in AD 1670. Eighteen single-ring samples were dated by the 14C laboratories at Groningen, Oxford, and SUERC: each laboratory was sent a random selection of 6 samples. This approach was intended to mimic the mix of samples and relative ages incorporated into Bayesian chronological models during routine project research. This paper presents the results of this study.