Neutron activation analysis of fine grey pottery from Conimbriga,Santa Olaia and Tavarede,Portugal

The concentrations of two major elements and thirteen trace elements in 73 selected sherds of fine grey ware from the Iron Age and Roman period, excavated at Conimbriga, Santa Olaia and Tavarede, Portugal, were determined by instrumental neutron activation analysis. These concentrations were used to calculate distance matrices which were then subjected to cluster analysis employing SAHN and k-means methods, as well as to principal components analysis, to group the sherds according to the overall similarity of their compositional characteristics. The results showed that equivalent groupings appeared regardless of the taxonomic method used. Two major clusters were recognized corresponding to two different sites, namely Conimbriga and Santa Olaia, suggesting that the ceramics from these sites were made locally. No significant differences in compositional patterns were observed between iron age and roman sherds from Conimbriga.     

Sapwood estimates in the interpretation of tree-ring dates

Many timber finds lack some or all of the outer, sapwood rings formed in the years just before felling. In order to estimate felling date once the outermost remaining ring has been dated, it is necessary to estimate the number of sapwood rings originally present. Methods doing this for oak are reviewed in the light of an intensive study of living trees at one site and an extensive study of 175 samples from living trees in North Wales and northwest England. Some methods reported in the literature are found to be invalid. A method reported by Hollstein (1965) is most reliable, with modifications for known variations in sapwood number with position in the tree. At present the best available estimate is that a value of 30 sapwood rings be used (95% confidence limits: 19–50).     

Living on the Edge? Transformation of a Marginal Pleistocene Landscape Into a Settlement Area in the Northeastern Part of the Netherlands

ABSTRACT

This paper will examine settlement location during the Iron Age in the northeast part of the Netherlands, an area shaped by Pleistocene geology. In recent years, a number of Late Iron Age/Early Roman settlements situated on the low lying slopes of sand ridges and nearby stream ridges revealed traces of an earlier Iron Age occupation. Palynological data revealed that this part of the landscape was used by humans before it was transformed into an area of settlement. An analysis of excavation data from two key sites at Denekamp-De Borchert and Groningen-Helpermaar, as well as other known sites, lead to the conclusion that the transformation of ‘peripheral landscapes’ into permanent settlement locations was preceded by a phase of arable cultivation which left no trace of permanent habitation. It is also suggested that the impact of human behaviour on the natural landscape in the Early and Middle Iron Age was much bigger than previously anticipated. When excavating this type of settlement areas dating to the Late Iron Age, archaeologists must be aware that only of a small group of archaeological features exist. The proposed model for the choice of settlement location may be more widespread, because of similarities in landscape between the study area presented here and other landscapes in Northwest-Europe (e.g. parts of Germany and Denmark).     

A Bayesian approach to rapid seismic vulnerability assessment at urban scale

The seismic vulnerability of city centers is commonly assessed by extending the study methods applied to single buildings to urban aggregations. This approach is not always applicable at territorial scale, as it is uneconomical in terms of time and costs. An innovative method provides reasonable large-scale a priori estimation of parameters not directly evaluable from the exterior of buildings by elaborating values which can be measured from the outside. Those parameters are treated as continuous variables, by assigning them a suitable probability density function. The Bayesian approach is adopted, which allows the update of initial hypotheses by using new data gathered during on-site surveys. In this regard, a rapid survey form for the on-site data collection is proposed. An example of its application to a façade of a building structural unit in Santo Stefano di Sessanio in L’Aquila province (Italy) is proposed, showing promising preliminary results for buildings belonging to Italian historical centers.     

Middle Bronze Age Arsenical Copper Alloys in Southern Portugal

In the Iberian Peninsula, the copper metallurgy from the Chalcolithic to the Middle Bronze Age (MBA) was mostly characterized by low arsenic contents. A collection of 53 MBA artefacts from southern Portugal was analysed by micro‐EDXRF, optical microscopy, SEM–EDS and Vickers to investigate the metal composition and manufacture. No technological distinction was found between artefacts from domestic and funerary contexts, which were radiocarbon‐dated to 2000–1500 cal bc . The arsenic contents of almost 100 MBA artefacts from this region, including the above‐mentioned set, have a Gaussian distribution with a high average (3.9 wt% As). Possible explanations are discussed for this distinctive metallurgy at the south‐western end of the Iberian Peninsula.     

3D Digital Survey of Iron Tie-Rods in Masonry Buildings: Cross-Sections Analysis and Error Estimation

Ancient iron tie-rods are handcrafted elements with large geometric irregularities, due to production techniques (they are shaped by hammering and linked by hot-forging) and corrosion processes. In common practice, their cross section (that is one of the main parameter to assess their strength) is manually measured on site with a manual caliber. By analyzing a set of detailed three-dimensional (3D) digital surveys of real ancient tie-rods, this study provide an evaluation of the errors made by in-situ manual geometric measurements. In particular, it shows that, in some cases, manual on-site survey is sufficiently reliable and has errors that fall below 10%. Moreover, it shows that when tie-rods have high corrosion levels in hidden zones (typically those close or within the retaining walls) the on-site survey of visible parts only may produce far greater errors that exceed 100%, leading to a strong overestimation of the cross-section of the tie. The ongoing study is a first step toward the definition of correction coefficients to be applied to the on-site manual measurements of ancient tie-rods, with the final aim to improve the reliability of structural analyses.     

Quantifying artefacts over time: Interval estimation of a Poisson distribution using the Jeffreys prior

This paper presents a new method for estimating the amount of an artefact class in use at a given moment in the past from a random assemblage of archaeological finds. The method is based on the use of simulation, since an analytical solution is computationally impractical. Estimating the number of artefacts in use at any time t is shown to follow a Poisson distribution, which allows for credible intervals to be established using the Jeffreys prior. This estimator works from minimal assumptions about the dating and duration of finds, as well as the intensity of collection, and is applied to coinage from four Roman‐period sites excavated by the Roman Peasant Project (2009–14). The result provides an estimation of the abundance of material according to an interval of certainty.     

Collagen deamidation in archaeological bone as an assessment for relative decay rates

Attempts to extend methods for dating archaeological bones beyond that of radiocarbon dating, such as amino acid racemization, have met with limited success owing to the dependence on multiple environmental factors and controls. Despite facing similar challenges, deamidation of glutamine has recently been investigated as a potential indicator of ‘thermal age' in archaeological bones, as well as a measure of their preservation quality. In this study, we undertook a series of simulated diagenetic experiments to understand the various factors affecting deamidation. Further, we analysed bones from different Middle Palaeolithic layers from Grotte Mandrin (France), with the results suggesting potential use of deamidation for relative dating, but only in case of extremely well‐preserved layers. The results also suggested the possible use of attenuated total reflectance‐Fourier transform infrared (ATR‐FTIR) spectroscopy as a screening test for soluble collagen before proteomic analysis.     

Add shamans and stir? A critical review of the shamanism model of forager rock art production

The “shamanism” or “neurpsychological” model proposed by Lewis-Williams and colleagues has had a powerful impact on rock art research, and has significantly added to our knowledge of past foragers lifeways in southern Africa and elsewhere in the world. However, this model is primarily based on the view of shamanism as a universal and unvarying characteristic of foragers over space and time. This paper raises both theoretical and empirical problems with this view. The paper examines the relationship between the specific social roles and practices of shamanism and the overarching cosmological structures on which they are based in both southern Africa and Northern Eurasia. In both cases, the paper argues that many cosmological beliefs are highly persistent and durable, extending into prehistory, while the specific practices and roles of shamans are variable, changing to meet the immediate and local needs of their communities. This suggests that rock art is easier to relate to the overarching cosmological dispositions of the people that produced it and the paper closes by suggesting some theoretical and methodological alternatives recognizing this fact.     

Homemaking and Mature Age Gay Men ‘Down-Under’: Paradox,intimacy, subjectivities,spatialities, and scale

The article investigates homemaking processes of mature age gay men living in a provincial Australian town. All too often the experience of older gay men living in non-metropolitan centres has slipped the attention of scholars. The article draws on interview data collected in Townsville (Queensland, Australia) from ten men over 40 years of age who self-identified as gay. These men were asked to explain why they live in Townsville, their understanding of home, and if they understand Townsville as home. We investigate the spatialised understandings of home articulated by these gay men, focusing on two mutually constituted geographical scales: Townsville-as-home and house-as-home, including the material objects within domestic space. For older gay men to call a provincial town home is an ongoing, complex process of reconciling multiple and contradictory subjectivities across different geographical scales. How older gay men constitute Townsville-as-home provides important insights about both non-heterosexual life in provincial centres and how to conceptualise home—as a paradoxical space, contested site, and as multiscalar.