A new approach to study the fuel used in hearths by hunter-gatherers at the Upper Palaeolithic site of Abri Pataud (Dordogne,France)

The fuel used in hearths in the Upper Palaeolithic period and the management of this fuel have long given rise to questions on intentional or opportunistic human comportment. To understand how fuel was managed during the Aurignacian and Gravettian cultures, hearth samples from the French site of Abri Pataud (ca. 34–20 kyr BP) were collected. An image analysis method for the automated quantification of burnt particles from macroscopic-to-microscopic sediment fractions was developed, and the results obtained using this method were compared with the palaeoenvironmental data available close to the site. At Abri Pataud, the use of bones was dominant during the Pleniglacial, suggesting an intentional practice. However, environmental pressures could have influenced the fuel management practices of the hunter-gatherers, even if the dualistic relationship between the availability of firewood and the use of bone in hearths must be considered. Thus, burnt particle quantification provides more than just an observation of burnt macroremains in hearths: it relates to fundamental information on human behavior.     

Going underground: experimental carbonization of fruiting structures under hearths

We show that carbonized fruits and seeds recovered from Middle Stone Age deposits in rock shelters are likely to have been carbonized as part of post-depositional processes. We buried indigenous South African fruits, nuts and seeds at pre-determined depths and distances from the centers of experimental fires. The cold ashes of the hearths and the sand surrounding them were subsequently excavated, using standard archaeological techniques and dry-screening. The fruiting structures from the oxidizing part of the fire were burnt to ashes, whereas those buried in sand under anoxic conditions survived in varying forms. Those buried 5 cm below the center of the fire were carbonized; those buried 10 cm below the center of the fire were dehydrated; and those 5 cm and 10 cm below the surface at the outer edge of the fire were unaffected. Size, moisture or oil content of the original fruit or seed did not appear to influence whether or not carbonization took place. Temperatures recorded 5 cm below the experimental fires suggest that the carbonization occurred at or before a maximum temperature of 328 °C, and also at lower maximum temperatures (152 °C) that were maintained for long periods. Even when the quantities of a particular wood are controlled, open fires may produce variable underground temperatures and the temperatures below ancient hearths would have been equally variable. We suggest that Cyperaceae (sedge) nutlets, the most numerous fruiting structures in the Sibudu Middle Stone Age archaeobotanical assemblage, occur in the shelter as a result of human activity, subsequent burial, and accidental carbonization when hearths were built directly above the buried nutlets.     

Interpreting Intra-site Spatial Patterns in Seasonal Contexts: an Ethnoarchaeological Case Study from the Western Alps

This paper deals with the ethnoarchaeological analysis of the spatial pattern of artefacts and ecofacts within two traditional pastoral huts (a dwelling and a seasonal dairy) in the uplands of Val Maudagna (Cuneo province, Italian western Alps). The composition of the ethnoarchaeological assemblages of the two huts was studied and compared; point pattern analysis was applied to identify spatial processes mirrored in the interactions between objects; Moran’s I correlogram and empirical variogram were used to investigate the effects of trampling on the displacement of objects on the floor. The results were compared with information provided by the herder who still used the huts. The quantitative and ethnographical data enabled inferences to be made that can help in the interpretation of archaeological seasonal sites. The function of a seasonal site can be recognized, as can the impact of delayed curation on the composition of the assemblage and the importance of the intensity of occupation compared with the frequency of occupation. The spatial organization of activities is reflected in the spatial patterns of objects, with clearer identification of activity areas in intensively occupied sites, and there is evidence for the behaviour behind the spatial segregation of activities. Trampling is a crucial post-depositional factor in the displacement of artefacts and ecofacts, especially in non-intensively exploited sites. From a methodological point of view, this research is another example that highlights the importance of integrating quantitative methods (especially spatial analysis and geostatistical methods) and ethnoarchaeological data in order to improve the interpretation of archaeological sites and assemblages.     

Luminescence dating of prehistoric hearths in Northeast Qinghai Lake and its paleoclimatic implication

Archeological research has been trying to provide evidence relevant to understanding both the timing of and processes responsible for human colonization of the Qinghai-Tibetan Plateau (QTP). Hearth is one of the most extensive, important, and typical prehistoric humanity activity evidence on the QTP. However, there are a number of hearths lacking charcoal material because of the wind and water erosion. Fortunately, most of these hearths can be dated by luminescence dating on the remnant sediments around the hearth. In this study, 18 optically stimulated luminescence (OSL) samples from 14 hearths in Yandongtai site (YDT) and Bronze Wire site (BW) in the northeast of Qinghai Lake area were systematically dated. The OSL ages range from 6.8 ± 0.7 to 14.4 ± 1.2 ka. There is a good agreement between OSL dating results and charcoal ages during the last deglaciation period, which indicates that OSL method has great potential in dating hearth on QTP. Combined with the previous dating results from other hearths, the age of hearths concentrates in 11–13 ka BP, i.e., the Younger Dryas (YD) chronozone. The increased number of hearths indicates reinforced colonization in the Qinghai Lake area during YD cold event, implying that the cold climate during YD event was not severe enough to hinder the inhabitation of prehistoric humanity at an elevation of 3.2 km.     

Organic Loss in Drained Wetland Monuments: Managing the Carbon Footprint

Abstract

The recent installation of land drains at Star Carr, Yorkshire, UK, has been linked with loss of preservation quality in this important Mesolithic buried landscape, challenging the PARIS principle. Historically captured organic carbon, including organic artefacts, is being converted to soluble organic compounds and less soluble carbon gases. At the same time sulphur and nitrogen compounds are oxidized to species that are chemically destructive of artefacts and ecofacts. Two of the carbon products, CO₂ and methane, are ‘greenhouse gases’ whose environmental impact can be costed in terms of carbon equivalents, which can be set against an assessment of the gain in agricultural productivity of the land arising from drainage, at Star Carr being the improved cereal crop. Wetland studies elsewhere suggest that such decay processes could be slowed by restoring the historic soil environment, and even reversed to create carbon capture, enabling the farmer to claim carbon credits.     

Fire and ritual: bark hearths in South-American Tupiguarani mortuary rites

High proportions of bark pieces (up to 85% of the charcoal content) were found in several hearths from Morro Grande archaeological site (Southeastern Brazil). This site, dated between 3220–2840 and 1820–1390 yrs cal BP, is associated to the Tupiguarani Tradition, attributed to supposed ancestors of Tupinambá native populations, who occupied the major part of the Brazilian coast in the XVIth century. Bark hearths, archaeologically associated with the mortuary ritual, were found encircling a funerary urn and associated with ceramic fragments painted with elaborated patterns in black, white, and red. Other hearths, spatially isolated from the funerary area, were associated to fragments of utilitarian non-painted ceramics and therefore attributed to domestic contexts. These ones presented few or no bark fragments. It is clear that bark was intentionally selected as fuel for the funerary hearths. Although bark is related, in historic accounts, as a specialized firewood for ceramics firing, its presence in ritual context has not been previously recorded. In this paper, the anthracological record is discussed in the light of ethnographic and historic accounts. A possible explanation for the presence of bark hearths in funerary context is proposed, suggesting it might be a symbolic parallel with the quotidian: the potency and power of transformation of bark as a fuel would be regarded in a spiritual level, achieving the transformation of the body soul in the revered soul – an Ancestor.     

The Early Mesolithic Haverbeck site,Northwest Germany: evidence for Preboreal settlement in the Western and Central European Plain

Archaeological sites dating from the Preboreal are of special interest since they mark the turning point in the transition between the cultures of the Late Pleistocene and the Holocene. In spite of their relevance only few sites in the Western and Central European Plain have become known, thus providing an inhomogeneous basis for further hypotheses. In particular, sites in the widespread aeolian landscapes have been neglected for a long time due to their uncertain genesis, dating problems and obviously insufficient preservation. Our investigations of the Haverbeck site, situated in sandy aeolian substrate, seek to enhance knowledge about the Preboreal Mesolithic. The well-preserved archaeological spatial, technological and functional patterns and the geoarchaeological site formation were studied. Sedimentological and palaeopedological analyses, supported by ¹⁴C and OSL dating results, revealed that artefacts were deposited during the Preboreal on sands which had accumulated during the Younger Dryas and were reactivated in subsequent periods (Atlantic, Subboreal, Subatlantic). In spite of these processes, the artefacts remained unimpaired in their relative horizontal positions, enabling spatial analyses, which show a zonal differentiation and a prevalence of retooling and replacing activities. These results offer an insight into spatial and functional differentiations of the local Early Mesolithic subsistence, evidently including particular places for gathering and processing raw material. A comparison between the microlithic spectrum left behind and the number of points produced as concluded from the microburins indicates a greater typological differentiation than previously assumed for the Early Mesolithic. The remarkable variability of scraper forms obviously intentionally abandoned in a high number and replaced by new tools emphasizes the strong influence of functional elements on the typological assemblage composition. It is suggested that Early Mesolithic assemblages could display rather functional requirements or tasks performed than significant chronological or regional influences.     

Intra-site Spatial Analysis in Ethnoarchaeology

ABSTRACT

The interpretative power of quantitative intra-site spatial analysis has long been recognised by archaeologists. On the contrary, very few ethnoarchaeological works have engaged with the statistical analysis of intra-site pattern of artefacts and ecofacts. Nonetheless, ethnoarchaeology is uniquely placed to guide and assist in the identification of sound techniques and in the development of the methodology of analysis. The possibility to directly connect the distribution of the proxies under study with the activity that generated such distribution, provide the means of fine-tuning the tools we use for identifying these patterns in the archaeological record. As a consequence, archaeological methodology and interpretation both benefit from the application of improved methodologies. In this paper we review some of the most common techniques used to analyse activity areas and we provide examples of the application of such techniques to ethnoarchaeological contexts. The aim is to assess how archaeology can benefit from the intra-site spatial analysis of ethnoarchaeological contexts.     

Charcoal scarcity in Epigravettian settlements with mammoth bone dwellings: the taphonomic evidence from Mezhyrich (Ukraine)

Fuel management during the Paleolithic periods is an important issue to understand past human subsistence. Numerous Palaeolithic sites relate an abundance of burnt bones in hearths and an absence or scarcity of wood charcoals, which leads studies to focus on burnt bone remains and the use of bones in hearths. Few works take into account the micro-residues of wood charcoals which can still be present in hearth areas and excavated sediments. We studied the Epigravettian site with mammoth bone dwellings of Mezhyrich (Ukraine) previously characterized by its high content of burnt bones and an “absence” of wood charcoal during the so-called mammoth steppe. The presence or absence and proportions of both wood charcoals and burnt bones were quantified in macro-, meso- and microscale sediment size fractions by an image analysis method. Our results show that excavations during field-works at Mezhyrich give only a partial image of the original anthracological record and that most charcoal materials are lost with standard archaeological and anthracological approaches. The scarcity of charcoals in this site was possibly due to an important mass reduction accentuated by the addition of bones in hearths. By applying our protocol we recovered a significant amount of wood charcoals which provides the first ¹⁴C dates from charcoals at Mezhyrich. Numerous charcoals are identified contributing subsequent information about vegetation, environment and burning practices. They indicate, by comparison with pollen data already collected, the presence of forest patches in a mammoth steppe landscape, which might have influenced the collecting behavior of Epigravettian populations.     

RADIOCARBON DATING OF MESOLITHIC OPEN‐AIR SITES IN THE COVERSAND AREA OF THE NORTH‐WEST EUROPEAN PLAIN: PROBLEMS AND PROSPECTS

This paper discusses the problems with sampling materials and sampled contexts in the framework of radiocarbon dating of Mesolithic sites situated in generally dry, acid and bioturbated coversand deposits within north‐western Europe. The case studies presented all relate to the coversand regions of northern Belgium and the Netherlands, two areas for which very large sets of radiocarbon dates performed on different organic components are currently available. The study points out that charred hazelnut shells from surface hearths and charcoal from hearth pits guarantee the most secure dating results, while the dating of calcined bones and food crusts from Final Mesolithic pottery so far remains problematic.     

NEW RADIOCARBON ACCELERATOR DATES ON ARTEFACTS FROM THE EARLY MESOLITHIC SITE OF STAR CARR,NORTH YORKSHIRE*

For the well‐known early Mesolithic site of Star Carr, dating of organic artefacts by accelerator mass spectrometry (AMS) has been hampered by treatment of bone and antler recovered during the original excavations with preservatives. Some, untreated, artefacts were, however, collected after Clark's excavation in 1950. Four of these artefacts were AMS dated in 1995, but two of the dates were significantly younger than the others, and were questionable due to their low collagen yields. These suspect samples have now been re‐analysed, demonstrating that all four artefacts are of similar date. The significance of these dates for the chronology of Star Carr is discussed.     

Tools for Predicting Damage to Archaeological Sites Caused by One-Dimensional Loading

Tools are developed to predict damage to archaeological remains caused by the construction of line infrastructure on soft soil. They are based on numerical modelling and laboratory testing supported by X-ray microcomputed tomographic observations, and micromorphological analyses of thin sections. They have been validated for one-dimensional (1D) loading at two sites in the Netherlands where soil has been placed on top of organic layers rich in ecofacts and overlaying Pleistocene sands.

Numerical prediction of the deformation of soft layers underneath an embankment remains a challenge for geo-technical engineers. Errors on surface settlement prediction reach ±15% of the measured total settlement.

Laboratory observations show that vulnerable artefacts can get crushed when packed loosely in pure assemblies under 1D loading equivalent to less than 5 m of sand. Fragmentation is assimilated to loss of archaeological value as it compromises recovery during sieving. Embedment in a sandy or a very compressible organic matrix has a beneficial effect on the resistance of ecofacts. Embedded ecofacts can resist a load of more than 12 m of sand. Flattening and re-orientation of soft plant remains occur during 1D loading without microscopic damage of tissues.     

Pitted stone cobbles in the Mesolithic site of Font del Ros (Southeastern Pre-Pyrenees,Spain): some experimental remarks around a controversial tool type

The presence of cobbles with activity-related marks in the Mesolithic site of Font del Ros (Berga, Spain), and in particular one group of artefacts – pitted stones – raises problematic issues associated with the characterization of percussion activities. Although these artefacts have generated an extensive bibliography on ethological, ethnographic, ethnoarchaeological and archaeological levels, various questions persist in relation to their possible contextual function. In this paper we present the results of an experimental programme in which three types of activities that could create pitted stones are reproduced: bipolar knapping of vein quartz, hazelnut cracking, and hazelnut grinding. The aim of this experimental programme is to describe marks and use-wear traces related to such activities.     

Establishing discovery probabilities of lithic artefacts in Palaeolithic and Mesolithic sites with core sampling

This paper reports the results of a study into the effectiveness of core sampling for discovering Palaeolithic and Mesolithic hunter-gatherer sites in the Netherlands and northwestern Belgium. Earlier work established optimal sampling strategies for use in archaeological heritage management survey in the Netherlands. However, the statistical model used for this was based on a limited amount of data on the distribution of lithic artefacts in Palaeolithic and Mesolithic sites. For the current study we have analyzed the distribution of artefacts in a selected number of excavated sites, and estimated discovery probabilities of these sites through simulation. The simulation results indicate that discovery probabilities are lower than expected due to the effect of clustering of finds. Furthermore, the density of flints in Palaeolithic and Mesolithic sites is generally lower than the estimates that were used for setting up the optimal sampling strategies, and a substantial number of sites is very small. This means that, in order to discover Palaeolithic and Mesolithic sites with sufficient reliability, we will have to apply more intensive survey strategies than have been recommended up to now.     

Soil geochemistry and detection of early Roman precious metal and copper alloy working at the Roman town of Calleva Atrebatum (Silchester,Hampshire, UK)

A geochemical soil survey was carried out over 500 m² of a first and second century AD house complex in insula IX of the Roman town of Calleva Atrebatum (Silchester, Hampshire, UK) where there was little prima facie evidence for non-ferrous metalworking. Preliminary analyses were made by XRF of lead, zinc and copper. These were followed by analysis for Au, Ag and Sn by ICP-MS of the samples with the highest concentrations of Pb, Zn and Cu. Certain of the Pb, Zn and Cu concentrations suggest the working of copper alloy including brass, and could be associated with archaeological evidence of hearths and burnt areas of second century AD date. Other samples have concentrations of the above metals and of gold and silver which do not appear to be associated with any physical remains of hearths and burnt areas. These concentrations date to the mid-first century AD.     

ARCHAEOMETRIC STUDY OF SHELLS OF HELICIDAE FROM THE EDERA CAVE (NORTHEASTERN ITALY)*

The Edera Cave, near Aurisina in the Trieste Karst, retains a stratigraphy that extends from the Mesolithic to the modern era. At Sauveterrian layers, many specimens of Helix cincta are present, which are considerably crushed, and a small percentage of which are also blackened. Chemical analyses show that the blackened specimens were exposed to a temperature of between 500 and 550°C, and suggest that many others were destroyed by fire at temperatures of above 700°C. Consequently, only a part of the Helix cincta shells is assumed to be the residue of human meals, since several factors render plausible an accidental combustion of shells already present in the ground before the lighting of Mesolithic hearths.     

A pilot study of “black chert” sourcing and implications for assessing hunter-gatherer mobility strategies in Northern England

Mesolithic hunter-gatherer logistic strategies and raw material procurement locales have been topics of considerable interest in northern England, accelerated by the early discoveries at Star Carr. Here we present the results of a pilot study investigating the potential for geochemically sourcing “black chert”, a material with similar qualities to flint but of inland limestone origin, using ICP-AES, ICP-MS and LA-ICP-MS. Several geological sources of black chert are known, and it is commonly present at upland Mesolithic sites along the Pennine chain. Four geological sources were sampled and analysed, along with a small sample of black chert artefacts from two upland Pennine archaeological sites. The results demonstrate that the four sampled sources can be easily differentiated from one another chemically. This research reveals the potential to apply this approach at a larger scale; the archaeological sample together with the source results indicate that additional sources will need to be identified and sampled before such data can be applied to address current questions of the Mesolithic of northern England.     

Prior to Peat: Assessing the Hiatus between Mesolithic Activity and Peat Inception on the Southern Pennine Moors

Palaeoecological investigation of soils exposed by eroding peat haggs on the moors above Tintwistle (Derbyshire) suggests that Mesolithic impact on upland soils between c. 360–500 m OD was not as dramatic, nor as long-lasting, as has sometimes been suggested. Despite evident erosion prior to peat inception, patterning has survived within Mesolithic scatters of artefacts. Neolithic activity is attested by both artefacts and charcoal-rich horizons suggesting intermittent burning of vegetation. Peat finally blanketed these uplands around the start of the second millennium cal. BC.

These results demonstrate radically different scenarios at different altitudes within relatively small distances across the southern Pennines, shifting our appreciation of the chronology of changes in vegetation and erosion, as well as contributing to wider debate on the causes of moorland development, which can inform future land management.     

Bedding, hearths, and site maintenance in the Middle Stone Age of Sibudu Cave, KwaZulu-Natal, South Africa

Micromorphological analysis of sediments from the Middle Stone Age site of Sibudu Cave, KwaZulu-Natal, South Africa, provides a high-resolution sequence and evidence of site formation processes of predominantly anthropogenic deposits. This methodology allows for a detailed interpretation of individual anthropogenic activities, including the construction of hearths and bedding and the maintenance of occupational surfaces through the sweep out of hearths and the repeated burning of bedding. This analysis also provides a context for evaluating other studies at the site relating to magnetic susceptibility, paleobotany, paleozoology, anthracology, and studies of ochre.