scholarly journals The origins of agriculture in Iberia: a computational model

2015 ◽  
Vol 42 ◽  
Author(s):  
Salvador Pardo Gordó ◽  
Joan Bernabeu Aubán ◽  
Oreto García Puchol ◽  
Michael Barton ◽  
Sean M. Bergin

Here we discuss the importance of using the rich and growing database of high-precision, audited radiocarbon dates for high-resolution bottom-up modelling to focus on problems concerning the spread of the Neolithic in the Iberia. We also compare the spread of the Late Mesolithic (so-called Geometric) and the Early Neolithic using our modelling environment. Our results suggest that the source of radiocarbon data used to evaluate alternative hypotheses plays an important role in the results and open up new lines of research for the future.

2018 ◽  
Vol 83 (3) ◽  
pp. 505-524 ◽  
Author(s):  
Paul M. Ledger ◽  
Véronique Forbes ◽  
Edouard Masson-Maclean ◽  
Charlotta Hillerdal ◽  
W. Derek Hamilton ◽  
...  

This article presents the results of a program of radiocarbon dating and Bayesian modeling from the precontact Yup'ik site of Nunalleq (GDN-248) in subarctic southwestern Alaska. Nunalleq is deeply stratified, presenting a robust relative chronological framework of well-defined individual house floors abundant in ecofacts suitable for radiocarbon dating. Capitalizing on this potential, we present the results of one of the first applications of Bayesian statistical modeling of radiocarbon data from an archaeological site in the North American Arctic. Using these methods, we demonstrate that it is possible to generate robust, high-resolution chronological models from Arctic archaeology. Radiocarbon dates, procured prior to the program of dating and modeling presented here, suggested an approximately three-century duration of occupation at the site. The results of Bayesian modeling nuance this interpretation. While it is possible that there may have been activity for almost three centuries (beginning in the late fourteenth century), occupation of the dwelling complex, which dominates the site, was more likely to have endured for no more than a century. The results presented here suggest that the occupation of Nunalleq likely encompassed three generations beginning cal AD 1570–1630 before being curtailed by conflict around cal AD 1645–1675.


Radiocarbon ◽  
2021 ◽  
pp. 1-16
Author(s):  
Anders Fischer ◽  
Jesper Olsen

ABSTRACT The Nekselø Wickerwork provides an unusually solid estimate on the marine reservoir age in the Holocene. The basis for this result is a 5200-year-old fish weir, built of hazel wood with a brief biological age of its own. Oysters settled on this construction. They had lived only for a short number of years when the fence capsized and was covered in mud and the mollusks suffocated. Based on the difference in radiocarbon (14C) age between accelerator mass spectrometry (AMS) samples of oyster shells and wood, respectively, the marine reservoir age for this site is estimated to 273 ± 18 14C years. Re-evaluations of previously produced data from geological and archaeological sites of Holocene date in the Danish archipelago indicate marine reservoir ages in the same order as that of the Wickerwork. Consequently, we recommend the use of the new value, rather than the ca. 400 14C years hitherto favored, when correcting for the dietary induced reservoir effect in radiocarbon dates of humans and animals from the Late Mesolithic and Early Neolithic periods of this region.


Author(s):  
Sérgio Monteiro-Rodrigues

Recentemente obtiveram-se cinco novas datações pelo radiocarbono para as ocupações holocénicas do sítio pré-histórico do Prazo. Quatro delas apresentam resultados compatíveis com os já divulgados em publicações anteriores. No conjunto, dispõe-se agora de uma série de vinte e seis datações 14C que seconsideram válidas. Estas datações permitem remeter a fase que se atribuiu ao Epipaleolítico para os finais do X/ meados do IX milénio cal BC; o Mesolítico mais antigo para o terceiro quartel do VIII milénio cal BC; o Mesolítico final para o período compreendido entre o segundo quartel do VII milénio cal BCe os meados do VI milénio cal BC; e o Neolítico Antigo para o intervalo balizado entre os finais do VI milénio cal BC e um momento indeterminado posterior ao terceiro quartel do V milénio cal BC. Entre estes períodos com ocupações humanas observam-se intervalos temporais para os quais não existem datações absolutas. Sugere-se que este facto possa estar relacionado com as dinâmicas sedimentares do local no decurso do Holocénico e não necessariamente com um padrão de povoamento caracterizado pela descontinuidade. New radiocarbon dating for the Holocene occupations of the prehistoric site of Prazo (Freixo de Numão, Vila Nova de Foz Côa, Northern Portugal) - Recently, five new radiocarbon dates for the Holocene occupations of the prehistoric site of Prazo were obtained. Four of them show results that are consistent with those previously published. At the moment, there are twenty-six 14C dates that are considered to be valid. These dates assign the supposed Epipalaeolithic to the end of the 10th/ middle of the 9th millennium cal BC; the earliest Mesolithic to the third quarter of the 8th millennium cal BC; the late Mesolithic to the interval between the second quarter of the 7th millennium cal BC and the middle of the 6th millennium cal BC; and the early Neolithic to the interval between the end of the 6th millennium cal BC and an undetermined moment after the third quarter of the 5th millennium cal BC. Among these periods with human occupation there are intervals for which there is no absolute dating. It is suggested that this may be related to the sedimentary dynamics of the site during the Holocene and not necessarily to a settlement pattern characterized by discontinuity.


2019 ◽  
Vol 114 ◽  
pp. 1-40
Author(s):  
Michael Fotiadis ◽  
Areti Hondroyanni-Metoki ◽  
Alexandra Kalogirou ◽  
Yannis Maniatis ◽  
Anna Stroulia ◽  
...  

Scores of Neolithic sites have been excavated in west Macedonia since the 1990s, yet the majority are relatively short-lived installations, lacking high-resolution stratigraphies and sequences of radiocarbon dates. Megalo Nisi Galanis, a large mound in the Kitrini Limni basin, near modern Kozani, is a rare exception to that pattern. Systematically surveyed and excavated in 1987–9 and 1993, this site covers a large part of the Neolithic period in a stratified, radiocarbon-dated sequence capped in places by thin deposits of the Early Bronze Age. We present here the critical details of that sequence and relate them to evidence from other, recently excavated sites in west Macedonia. Megalo Nisi Galanis was first settled in the Early Neolithic (late seventh millennium bc), was intensively occupied until the early phases of the Final Neolithic (around 4500 bc), and continued to be inhabited, albeit sparely or intermittently, until the transition from the Early to the Middle Bronze Age, about 1800 bc. By the end of occupation, the mound covered more than eight hectares and rose up to five metres above the surrounding landscape. We attend closely to features of that landscape that are likely to have played an important role in the history of occupation of the site and Kitrini Limni in the course of the Holocene.


2009 ◽  
Vol 71 (2) ◽  
pp. 99-107 ◽  
Author(s):  
Laura E. Beramendi-Orosco ◽  
Galia Gonzalez-Hernandez ◽  
Jaime Urrutia-Fucugauchi ◽  
Linda R. Manzanilla ◽  
Ana M. Soler-Arechalde ◽  
...  

AbstractA high-resolution 14C chronology for the Teopancazco archaeological site in the Teotihuacan urban center of Mesoamerica was generated by Bayesian analysis of 33 radiocarbon dates and detailed archaeological information related to occupation stratigraphy, pottery and archaeomagnetic dates. The calibrated intervals obtained using the Bayesian model are up to ca. 70% shorter than those obtained with individual calibrations. For some samples, this is a consequence of plateaus in the part of the calibration curve covered by the sample dates (2500 to 1450 14C yr BP). Effects of outliers are explored by comparing the results from a Bayesian model that incorporates radiocarbon data for two outlier samples with the same model excluding them. The effect of outliers was more significant than expected. Inclusion of radiocarbon dates from two altered contexts, 500 14C yr earlier than those for the first occupational phase, results in ages calculated by the model earlier than the archaeological records. The Bayesian chronology excluding these outliers separates the first two Teopancazco occupational phases and suggests that ending of the Xolalpan phase was around cal AD 550, 100 yr earlier than previously estimated and in accordance with previously reported archaeomagnetic dates from lime plasters for the same site.


Radiocarbon ◽  
2012 ◽  
Vol 54 (3-4) ◽  
pp. 783-794 ◽  
Author(s):  
Natalia E Zaretskaya ◽  
Sönke Hartz ◽  
Thomas Terberger ◽  
Svetlana N Savchenko ◽  
Mikhail G Zhilin

Two well-known archaeological sites, the peat bogs of Shigir and Gorbunovo (Middle Urals, Russia), have been radiocarbon dated (61 conventional and accelerator mass spectrometry [AMS] dates from various natural and artifact samples). For the first time, a detailed chronology of Early to Late Mesolithic and Early Neolithic occupation for this region has been obtained, and a paleoenvironmental history reconstructed. Based on these results, we propose that the Mesolithic settlement of the Middle Urals region started in the early Holocene, at the same time as in central and eastern Europe.


Radiocarbon ◽  
1992 ◽  
Vol 34 (3) ◽  
pp. 859-866 ◽  
Author(s):  
Ede Hertelendi ◽  
Ferenc Horváth

We investigated chronological questions of five Late Neolithic settlements in the Hungarian Tisza-Maros region. Fifty new radiocarbon dates provide an internal chronology for the developmental phases of the tell settlements, and place them into the wider framework of the southeastern European Neolithic. An example is presented of how a unique type of stratigraphic excavation helps the interpretation of radiocarbon data, which are in contradiction with the stratigraphic position of the samples.


2021 ◽  
Vol 13 (22) ◽  
pp. 4528
Author(s):  
Xin Yang ◽  
Lei Hu ◽  
Yongmei Zhang ◽  
Yunqing Li

Remote sensing image change detection (CD) is an important task in remote sensing image analysis and is essential for an accurate understanding of changes in the Earth’s surface. The technology of deep learning (DL) is becoming increasingly popular in solving CD tasks for remote sensing images. Most existing CD methods based on DL tend to use ordinary convolutional blocks to extract and compare remote sensing image features, which cannot fully extract the rich features of high-resolution (HR) remote sensing images. In addition, most of the existing methods lack robustness to pseudochange information processing. To overcome the above problems, in this article, we propose a new method, namely MRA-SNet, for CD in remote sensing images. Utilizing the UNet network as the basic network, the method uses the Siamese network to extract the features of bitemporal images in the encoder separately and perform the difference connection to better generate difference maps. Meanwhile, we replace the ordinary convolution blocks with Multi-Res blocks to extract spatial and spectral features of different scales in remote sensing images. Residual connections are used to extract additional detailed features. To better highlight the change region features and suppress the irrelevant region features, we introduced the Attention Gates module before the skip connection between the encoder and the decoder. Experimental results on a public dataset of remote sensing image CD show that our proposed method outperforms other state-of-the-art (SOTA) CD methods in terms of evaluation metrics and performance.


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