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This paper presents a methodological contribution to rock art archaeology by demonstrating the benefits of hyperspectral imaging, a relatively new method, for the understanding of rock art sites. It illustrates the complementarity of VNIR hyperspectral imaging, applied in rare cases to rock archaeology, and SWIR hyperspectral imaging, implemented here for the first time to a rock art panel. Applied to a schematic rock art site in southern France, the Otello rock shelter (Saint-Rémy-de-Provence, France), this method allowed the discovery of numerous new figures invisible to the naked eye or unsuspected after image enhancement with the DStretch plug-in of the Image J software, the individualisation of figures within complex superpositions as well as the discovery of figures covered by weathering products. Moreover, by conferring a spatial dimension to the analysis of pictorial matter, thus allowing a classification of pigments at the scale of the wall, hyperspectral imaging makes it possible to automatically isolate different paintings and to carry out objective groupings of figures on the basis of their composition. Finally, hyperspectral imaging allows us to precisely document, distinguish and characterise weathering products interacting with painted figures. For all of these reasons, this method appears essential to highlight the relative chronology and syntax of iconography, and consequently to understand its cognitive nature.

Western Arnhem Land in northern Australia has the rare distinction, both at national and global scales, of containing a vast landscape of many thousands of rockshelters richly decorated with art, some of which was probably made tens of thousands of years ago, others as recently as a few decades ago. Yet the challenge remains as to how to date this art, how to find out how old it is. While relative dating methods have been commonly applied, in particular patterns of superimposition and changing faunal themes supposedly signalling changing environmental conditions, we still lack a clear understanding of the age of almost all the region’s art styles or conventions.Other chapters in this volume report direct dates for Arnhem Land art using radiocarbon determinations on beeswax figures with the likelihood that the ‘art event’, the time when a beeswax figure was made, is at most a few years different from the ‘carbon event’, the time of the last biological capture of atmospheric carbon, which is the actual date measured by radiocarbon. But many, in fact most, sites have no beeswax figures or other ways directly to date the art. Sometimes, as again reported in this volume, there is some indication of date when a radiocarbon determination is obtained on, for instance, charcoal in an archaeological deposit that can be related to the art. Often that route is also blocked: many a painted surface without beeswax figures is in no close relation to a deposit that might so be dated. What can be done then? Here we present results of investigations at a small rockshelter in Jawoyn Country, in the centralwestern part of the Arnhem Land plateau. Since its art cannot be directly dated, we follow a different path. In the first instance, we aim to understand the history, and antiquity, of the decorated rock surfaces, since the exposed surfaces of the boulder have undergone repeated transformations over a long time. Determining when now-decorated rock surfaces were formed can give us maximum possible ages for the art, since we can date when the surface first was available. Taken with related archaeological evidence from deposits, such as ochre fragments with signs of use, we can arrive at some indications for the age of the art, or at least how the range of possible dates is constrained. This approach is akin to that used at other sites in Jawoyn Country (see Chapters 11 and 15)

In 2011, Gunn et al. published the discovery in a remote part of the western Arnhem Land plateau of a rock painting that closely resembles the most recent reconstructions of an extinct megafaunal bird, the dromornithid Genyornis newtoni. Characteristics of the painting distinguish it from depictions of other bird species and support its identification as G. newtoni: a deep convex bill, unlike the shallow bill of an emu or cassowary; a globular cranium and relatively thick neck; indication of a crop (emus and cassowaries lack crops); non-pendulous posture of the wing (unlike the pendulous posture of emus); the proportions of the pelvic limb showing long tibiotarsi and stout tarsometatarsi; the short, broad toes that appear to terminate in blunt claws; and a dorsal profile paralleling that of reconstructed dromornithids and unlike an emu or any species of cassowary, in which the vertex of the back is more anterior. The several points of special resemblance between the painting and reconstructions of the extinct bird based on paleontological evidence led Gunn et al. (2011:10) to conclude, ‘on the basis of probability the painting is indeed a representation of Genyornis newtoni’. This finding brings a conundrum. If the painting is indeed a contemporaneous depiction of G. newtoni, it becomes the oldest painting known in the world, for the bird is thought to have become extinct around 50,000 +/- 5000 years ago (Miller et al. 1999; Roberts and Brook 2010; Roberts et al. 2001) or even earlier (see Grellet-Tinner et al. 2016). Or that timing for the extinction of Genyornis is wrong; or a relic population survived longer on the Arnhem Land plateau (e.g. Murray and Vickers-Rich 2004), perhaps until the Last Glacial Maximum (LGM), which commenced around 25,000 years ago. And, as Gunn et al. (2011) acknowledged, there are still other alternatives. The painting might be of a ‘mythological’ animal: either one rooted in ancient memory of G. newtoni, as has been suggested for the ‘mihirung’ of southern Australian Aboriginal peoples (Vickers-Rich 1987) – although in societies without writing, social memory has not been found anywhere in the world to reliably extend in recognisable form over very long periods of time (cf. Bradley 2002) – or of a creature without a material counterpart that fortuitously resembled the fossil bird. The painting occurs on a vertical rock wall under a shallow overhang. Could the motif really have survived there since Pleistocene times, whether 25,000 or 50,000 years ago? And the painting shows a speared bird, so it could be the first evidence for the hunting of extinct megafauna in Australia. With these enigmas in mind, the Jawoyn Association asked us in 2010 to study the ‘Genyornis’ site, to investigate the age of the art and its archaeological and geomorphological context. Our major aims were to ask whether the painting dates, or theoretically could date, to the time of G. newtoni, or whether it must be more recent, and to uncover contextual ancient cultural information relating to the artworks and to occupation activities at the site in the past. Here, we present the results of these archaeological and geomorphological investigations along with a summary of the chemistry of the rock surface that houses the painting of the large bird thought by Gunn et al. (2011) to be of a Genyornis.

International audience; Analysing the colouring matter used to make prehistoric rock art is essential in order to retrace the chaînes opératoires involved. Despite the well-documented limitations of portable analysis systems, the need to conserve rock art led us to reassess the capabilities of portable X-ray fluorescence (pXRF) spectrometry. Thus, we compared in-situ and laboratory analyses of materials from the Points cave (France), and laboratory pXRF results with analyses obtained using other methods and with reference samples. Results confirmed that current pXRF systems are unable to provide data suitable for elucidating the chaînes opératoires of ferruginous colouring matter.

Although prehistoric sites frequently contain numerous fragments and traces of many different kinds of colouring matter, intensive study of this type of archaeological remains began only recently. Such studies, aimed at determining how raw materials formed and changed over time, and how they were transported by the groups of humans who used them, are extremely valuable as they reveal shared strategies, that is, cultural traditions and the spaces in which they developed. The scope of this paper focusses on the description of the main geological contexts in which ferruginous colouring materials form and are found. In the framework of a collective research program called Pigmentothèque (iron- and manganese-rich rocks and minerals library), geological surveys are conducted taking into consideration the geological settings in which colouring materials are present and using a common record and sampling methodology which is followed by petrophysical, mineralogical and chemical analyses based on a shared procedure and vocabulary. In order to go beyond descriptions based solely on colour and chemical composition, we describe the great variety of iron-rich materials that can be used to obtain colouring matter. This diversity in the formation and evolution of iron-rich materials must be taken into account when trying to understand past humans’ choices of raw materials, their provenance and the anthropogenic and natural modifications they have undergone. We also describe criteria for recognising cohesive remains of colouring matter during archaeological excavations, so these artefacts can take their place alongside other mineral resources in helping improve our understanding of past societies.

International audience; In the high mountain rock walls of the Mont Blanc massif, changes in the granite surface colour are related to its exposure age. The light grey colour of fresh rock surfaces turns orange when is long exposed to weathering. In order to study this colour/age relationship, reflectance spectroscopy was performed on 73 samples, and Terrestrial Cosmogenic Nuclide (TCN) dating was used to obtain their surface exposure age. The standard deviation of the reflectance values was calculated for each wavelength of the visible spectrum to study the behaviour of each spectral region. The aim was to find two colour regions that showed opposite behaviour, and once they are combined, they could provide a representative index of the rock colour changes that are linked to the degree of weathering.As an adaptation of the Green Red Vegetation Index used to measure colour changes in vegetation, the GReen-Infrared GRanite Index (GRIGRI), a normalized difference between the granite 770 nm and 530 nm reflectance values, was developed. The GRIGRI value of a weathered granite surface has a close relationship with its exposure age (R2 = 0.85). The reflectance spectra of seven samples for which TCN dating failed and two samples for which the TCN age was considered to be an outlier were used to calculate their GRIGRI value to assess the colour-based ages, that were plausible according to rock wall morphology and the TCN exposure ages of the surrounding surfaces. We propose a new method of surface dating for the rock walls of the Mont Blanc massif using reflectance spectroscopy.

mail janv/fev; International audience; Although the main prehistoric color used for paintings is red, knowledge of this coloring matter often boils down to saying that it is “ochre.” However, the red coloring matter of Prehistory is numerous and may have been the subject of various preparations, mixtures, or even alterations. Understanding the use and transformation of coloring matter raises questions about the technical processes but also about the supply strategies of these ancient societies. In the case of analysis of solid archaeological remains, we can access the petrography, mineralogy and chemistry of these ferruginous rocks. But, when it is about deposited powder, the means of investigation become limited. We therefore propose to test the complementarity of spectro-radiometry, a non-invasive method that allows us to obtain a spectral signature of the material whatever its mode of preparation. From six geological reference samples chosen for their color (from red to yellow) and for their mineralogical composition, spectra in the visible and near-infrared were recorded under several experimental conditions and several modes of preparation of the matter, using two spectro-gonio radiometers. It is then possible to discriminate these different coloring matter on the basis of their spectral signature and to understand the link with their mineral composition.

National audience; De Privas aux gorges du Gardon, de nombreuses ressources de matières minérales colorantes riches en fer sont disponibles dans les environs de sites ornés et d’habitat du Paléolithique supérieur au sein desquels des traces d’utilisation de telles matières ont été découvertes. La mise en contexte historique, mais aussi paléoanthropologique et paléoéconomique de ces deux types de site implique d’acquérir une bonne compréhension des réseaux pouvant exister entre eux, tout en intégrant les origines géologiques et géographiques des matières qui s’y trouvent. Ces objectifs constituent le socle du projet collectif de recherche Pigmentothèque. Nous focaliserons cet article sur les questions d’approvisionnement en matières colorantes au Paléolithique supérieur, sur les méthodes de documentation et de prospection ainsi que sur le contexte géologique et géomorphologique de la zone étudiée. Quatre formations géologiques serviront d’exemple pour évoquer la diversité de ces matières.

International audience; Understanding archaeological colouring matter commonly found at prehistoric sites is not always easy, because powdering, mixing and weathering blur the characteristics of its provenance. However, studying colouring and coloured artefacts enables the questioning of the processing techniques used to exploit them. Various studies are interested in recognizing these red colouring matter through their mineralogy, chemistry and petrography. Here, we seek to understand to what extent it is possible to isolate a spectral fingerprint of a ferruginous raw materials by radiospectrometry whatever their physical state (cohesive rock, powder, applied mixture on limestone). By using two spectro-gonio radiometers, we characterized the visible and near-infrared reflectance spectra of six geological references, selected for their singular mineralogical and chemical compositions as well as their hues. We identified single spectral signature for each reference. Furthermore, these signatures can be identified even in powders and mixtures due to mineral phase associations.

International audience; Several semantic web approaches tackle the problem of integrating multidisciplinary rich content using Linked Open Data. Cultural heritage (CH) is a multidisciplinary domain that contains a massive heterogeneous content that varies distinctly by types and properties. Various semantic web approaches have been proposed in the context of CH, and at multiple integration levels (local, national, international). These approaches focus on metadata schemata integration but give no significant importance to the representation of a tangible cultural heritage object, as a whole entity, and the different parts that compose it. Targeting the goal of the preservation and restoration of CH artifacts, we aim at modeling the CH content focusing on the composition of a CH object. We thus illustrate here an approach of using a part-whole and spatial relations to model the composition of a tangible object in general, and a CH object in particular. To do this, we introduce parthood concepts and properties for representing the composition mechanism, and 7 cases of parthood/spatial relations in tangible objects, with their corresponding logical/ontological relation(s). We implement our approach using OWL2 as the ontological language for our linked open data approach.

International audience; Post-glacial schematic rock paintings extend across the Iberian Peninsula to the Italian Piedmont. The Rocher du Château is one of the few Alpine sites with such painted figurations, located on a main transalpine route at 1750 m.a.s.l. in the Vallée de la Maurienne (Savoie, France). Archeological excavations in front of the painted panels revealed pigments and pigmented pebbles in archaeological levels attributed to the Neolithic Square Mouthed Pottery culture (SMP culture, 4600 –4000 BC). The co-existence of pigments from archeological soils and rock paintings is rare in European prehistory and exceptional for the Neolithic period. The integrated study of these materials, barely attempted before, combined non-invasive in situ methods (digital microscopy and Raman spectroscopy) and analytical studies of micro-samples (SEM-EDX, XRD). The weathering process on the rock surface before and after the layer of paint was studied, and the mineralogical identification of the pigments was analyzed. Complementary physico-chemical analyses were conducted at several scales of observation to identify the composition of the excavated pigments and pigmented materials. Some of them proved to be anthropogenic blends combining hematite and charcoal of plant origin. This association has never before been identified in other prehistoric European archeological sites. Based on these data, the potential links between the pebbles, the production of pigments, and the rock paintings are discussed.

We present Bayesian modelling on a long sequence of radiocarbon ages from the archaeological site of Nawarla Gabarnmang, central Arnhem Land plateau, northern Australia. A horizon of wind-borne sediments containing flaked stone artefacts and charcoal commencing >45,610 cal BP (the young end of the modelled boundary age range, which extends beyond the limit of the calibration curve), with a median modelled age of 48,500 cal BP, signals the onset of aeolian mobilisation of fine sands and silts across the landscape, and re-deposition within the site at a time synchronous with the first evidence of people. This earliest cultural horizon (Stratigraphic Unit 4) contains 509 stone artefacts, and is marked by a contemporaneous sedimentary break, from underlying culturally sterile sediments consisting of disintegrating roof-fall and in situ sandstone and quartzite to overlying culturally-rich wind-blown sand. The new radiocarbon ages and wind-blown sediments together provide evidence for the commencement of noticeable landscape burning on the Arnhem Land plateau c. 48,500 cal BP, suggesting an intensification of landscape management practices at the summit of the Arnhem Land plateau some 10,000 e15,000 years after the lowest dense band of artefacts (Phase 2) at Madjedbebe on the floodplains 90 km to the north. These results have ramifications for the structure and timing of the spread of people across Australia, and the extinction of megafauna in Sahul.

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The most common studies on colouring matter concern the question of the “chaîne opératoire” from procurement to use, dealing distinctively with archaeological remains and rock art. Only a few studies have been done on the link between excavated pieces and rock art, and even less have taken into account the correlation with geological origin. The “Grotte aux Points” presents the particularity of being decorated and archeological excavations reveal many pieces of coloured and colouring remains which are iron oxide-rich rocks brought to the site by Palaeolithic people. The red Palaeolithic paintings present a few palm-points, great signs and figurative drawings: a horse, a bison and ibexes.In 2015, coherent colouring matters, coloured limestone fragments and one µ-sample of painting were studied with complementary physico-chemical methods. To describe their morphology and composition, different instruments were used on macroscopic and microscopic scales: optical microscope, scanning electron microscope (SEM), and transmission electron microscope (TEM), both coupled with dispersive X-ray energy probe (EDX). 10 objects were studied using proton induced X-ray emission (PIXE) in order to obtain quantitative chemical data on major and trace elements. Except for the TEM which gives information concerning the iron oxide crystal morphology and potential heat-treatment, non-invasive and non-destructive methods have been privileged to preserve the archaeological artefacts.About forty pieces of solid colouring agents were excavated in the Palaeolithic occupational levels. Most of the pieces have millimetric size (< 5 mm). At least three different raw ferruginous materials were discriminated including a ferruginous clayey rock containing green minerals dispersed in the matrix. We think that this mineral phase, which still needs to be clearly identified, is a good indicator of the geological origin of this kind of rock.In addition, three centimetric fragments of wall painting (from 3 cm to 20 cm) were discovered at the foot of the “large signs” panel. Finally, in 2012, a red palm-point with black charcoal pigment superposition was sampled from the “Niche aux Points”.The twenty-five archaeological remains (coloured limestone fragments and solid colouring agents), the 3 painted wall fragments and the micro-sample of painting were analysed in order to approach the chronology of the colouring matter used.These observations combined with chemical measurements actually permit (i) to characterize the signal of the environment on the different objects, (ii) to identify differences between macro-observations and geochemical fingerprints on the coherent matters (figures 10, 11). The raw material properties privileged by Palaeolithic people during supply were identified. First results are encouraging and enable to improve the methodology, particularly on a chemical point of view., Les fouilles conduites sous le porche de la Grotte aux Points ont mis au jour des matières colorantes solides et des résidus colorés sur des clastes calcaires au sein des dépôts archéologiques Paléolithique supérieur. De plus, dans la partie profonde de la cavité, des écailles de paroi présentant des aplats rouges ont été découvertes au pied de parois ornées. Cette association offre l'occasion de questionner les relations entre ces vestiges sous l'angle des choix de matières premières et des modalités de transformation, informations qui participent à la définition du cadre chronologique de fréquentation de la grotte, tant au niveau de son entrée que de la galerie ornée. Nous avons ainsi déterminé, en les comparant, les particularités pétrographiques, minéralogiques et géochimiques de ces matières. L'approche multi-scalaire adoptée repose sur la complémentarité des méthodes d'investigation ce qui permet de distinguer plusieurs géomatières colorantes au sein du corpus. En particulier, certains dépôts sur les clastes peuvent être attribués à des causes taphonomiques, alors qu'une forte parenté a pu être établie entre une géomatière colorante solide et les aplats rouges sur écaille de paroi.

International audience; The Lesser Antilles are a densely populated region where local populations and industrial facilities are concentrated at the coastlines, and are therefore exposed to many rapid-onset hazards such as hurricanes and tsunamis. However, the historical catalog of these events is too short to allow risk assessment and return period estimations, and it needs to be completed with long-term records of washover deposits in coastal sedimentary environments such as lagoons. In this study, two sediment cores were taken in March 2018 in a small coastal lagoon on Scrub Island (northeastern Caribbean). Sedimentological, geochemical, microfaunal and chronological analyses enabled us to identify 25 sandy layers resulting from high-energy-marine floods. Two of these layers were interpreted as tsunami deposits based on sedimentological (rip-up clast of the underlying cohesive substrate and internal mud laminae), and geochemical evidence. The most recent deposit is associated with the transatlantic tsunami triggered by the 1755 CE Lisbon earthquake. The older one is the thickest sandy layer recorded in the lagoon, with an age range of 1364-1469 cal. CE, as determined using 14 C dating. This event was recorded in sedimentary archives of both the northern and the southern part of the Caribbean, with its large spatial extent, supporting a distant tsunamigenic origin. The 23 remaining sandy layers were interpreted as storm deposits, based on sedimentological and chronological data, with the three most recent layers being correlated with historical hurricanes. This new 1600 year-long record displays similarities with that of the Bahamas, with the periods of intense hurricane activity being in antiphase with those of the northeastern US coast. This regional comparison may provide evidence for a latitudinal forcing of hurricane tracks through time in relation to climate fluctuations.

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International audience; The materials used to make rock art contain important evidence about the cultural practices of the people who created it: their technologies, movements, and social interactions. The number of studies of archaeological pigments in the recent literature demonstrates how fruitful such enquiries can be. In this chapter, the authors discuss the physicochemical characterization of rock art pigments, outline the history of research in this area, differentiate key concepts and terminology, and describe principal methods. They conclude with illustrative case studies from France, South Africa, and Australia to demonstrate the kinds of archaeological information that can be preserved in rock art pigments.

Whether as engravings, drawings, paintings, stencils, or prints, rock art was made on rock surfaces devoid of protective coating. From the moment of its manufacture, it has therefore been subject to a range of environmental conditions and susceptible to a range of environmental impacts, each of which could have changed through time. In this chapter, the authors discuss the biotic, mechanical, and chemical processes that can affect rock art at its interface with the rock matrix and the atmosphere, together known as taphonomy. Given the complex interplay of age, environment, and processes, understanding alteration mechanisms affecting rock art sites and adequately assessing ways of mitigating deterioration require site-specific investigations and complementary scientific fields.

Western Arnhem Land, in the Top End of Australia’s Northern Territory, has a rich archaeological landscape, ethnographic record and body of rock art that displays an astonishing array of imagery on shelter walls and ceilings. While the archaeology goes back to the earliest period of Aboriginal occupation of the continent, the rock art represents some of the richest, most diverse and visually most impressive regional assemblages anywhere in the world. To better understand this multi-dimensional cultural record, The Archaeology of Rock Art in Western Arnhem Land, Australia focuses on the nature and antiquity of the region’s rock art as revealed by archaeological surveys and excavations, and the application of novel analytical methods. This volume also presents new findings by which to rethink how Aboriginal peoples have socially engaged in and with places across western Arnhem Land, from the north to the south, from the plains to the spectacular rocky landscapes of the plateau. The dynamic nature of Arnhem Land rock art is explored and articulated in innovative ways that shed new light on the region’s deep time Aboriginal history.

The archaeomorphological study of Nawarla Gabarnmang in Australia's Northern Territory challenges us to think in new ways about how Aboriginal people interacted with their surroundings; here a site of everyday engagement was a place of construction that retains material traces of past engagements. At Nawarla Garbarnmang, we show through archaeomorphological research how the changing physical layout of a site can be cross-examined against the impacts of human engagements through time. While the scope and scale of activities involved the anthropogenic removal over tens of thousands of years of rock pillars below the cave's roof, other practices came and went over time, the complex sequence of rock art conventions being an apt example. These artistic transformations, much like the era of pillar clearances, are a clear example of changing cultural practices in a part of Australia where some 50,000 years of human occupation can be shown.

The so-called “Genyornis” rockshelter site on the Arnhem Land plateau, northern Australia, features a painting of a large bird that some archaeologists and paleontologists have suggested could be an image of the megafaunal species Genyornis newtoni, until recently widely thought to have become extinct some 45,000 years ago. However, a recent archaeological–geomorphological study has concluded that the rock surface that contains the large, enigmatic bird painting only became exposed during overhang collapse between 13,739–13,976 cal BP, so the rock art on this panel can only be more recent than this age. It is, therefore, most unlikely to represent a Genyornis bird. Using a range of analytical techniques, here we report on the geochemistry (microstructure and chemistry) of the sequence of microlayers that makes up the “surface” of the rock at the “Genyornis” site. Our aim is to provide insights into the composition, preparation, source, application, weathering and preservation of pigment used in the making of the paintings, and to clarify the superimpositional order and relationships between the enigmatic large bird painting originally thought to possibly be of a Genyornis, and other nearby images. Micro-stratigraphic superimpositions show that the earliest painting was of a large anthropomorph, followed sometime later by the simultaneous painting of the large enigmatic (“Genyornis”) bird image together with a barbed spear image embedded in it. This significantly alters the perception of the paintings on the wall of this rockshelter, with relegation of the anthropomorph to the background, followed by the image of a speared large bird.

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International audience; This paper presents new results of on-wall and excavated pigments from two major rock art sites innorthern Australia: the ‘Genyornis’ site, and Nawarla Gabarnmang. The former site has been argued in the archaeologicalliterature to feature a painting of Genyornis newtoni, thought to have become extinct across Australia40-45,000 years ago. The second site, Nawarla Gabarnmang, has extensive paintings on its ceiling and pillar wallsas well as numerous coloured rocks (some of which are demonstrably ochre crayons) recovered by excavation.To determine the constituents and modes of preparation, pigment sources, and the potential antiquity of on-wallpaintings at the ‘Genyornis’ site, tiny pieces of both pigmented and unpigmented rock were sampled from the‘Genyornis’ panel. X-ray fluorescence, SEM-EDX, PIXE, Raman and infrared spectroscopies, and XRD analyseswere undertaken to determine the natural or cultural status of the excavated coloured rocks (potential ochre pieces)from Nawarla Gabarnmang.This paper presents results obtained so far.; Cet article présente les derniers résultats issus respectivement de l’étude de pigments prélevés sur unpanneau rupestre et de pigments excavés de deux sites majeurs d’art rupestre dans le nord de l’Australie : le sitede ‘Genyornis’, et Nawarla Gabarnmang. Il a été avancé dans la littérature archéologique que le premier siteabriterait la peinture de Genyornis newtoni, dont l’extinction est estimée à 40-45000 ans sur le continent australien.Le second site, Nawarla Gabarnmang, se caractérise quant à lui par un vaste ensemble archéologique dontles plafonds et les piliers sont recouverts de plusieurs générations de peintures ; les fouilles archéologiques ontpermis de mettre au jour une importante collection de blocs colorés (dont certains ont été identifiés comme étantdes crayons d’ocre).Afin de déterminer pour le site de ‘Genyornis’, les constituants des pigments utilisés, leur mode de préparation,leur origine géographique et la chronologie des peintures, des micro-échantillons de roche peintes et non-peintesont été prélevés sur le panneau ‘Genyornis’.Des analyses en fluorescence X, MEB-EDX, PIXE, spectroscopies Raman et infrarouge, et en DRX ont été misesen oeuvre afin de révéler le caractère naturel ou culturel des blocs colorés enfouis (ocres potentielles) provenant deNawarla Gabarnmang.Cet article présente les résultats obtenus à ce jour.

Organic matter (OM) entrapped in calcite is regularly used for environmental studies; however, insertion mechanisms and types of interaction remain poorly understood. The present study used a new methodology to investigate interactions between OM and the calcite matrix during crystallization processes with humic acid (HA) entrapment. A multimethod approach confirmed that HA is both adsorbed onto the calcite surface and incorporated into the calcite lattice during crystallization. Our results also confirm the log-linear correlation between fluorescence intensity and calcite matrix HA concentration. Fourier transform infrared spectroscopy showed that HA in colloidal conformation is adsorbed onto the calcite surface as a result of the structure of the OH stretching band. We also developed a new method based on synchrotron analysis that uses sulfur as a tracer element for entrapped HA and that localizes the OM electrostatically adsorbed onto the calcite surface. Changes in the sulfur environment, determined using X-ray absorption near-edge structure spectroscopy, indicated more complex insertion mechanisms than simple adsorption of HA during calcite crystallization. Desorption experiments revealed the stability of the OM atomic structure and its layered nature. These results allowed us to draw up a general model of OM insertion in calcite.

Recently, several techniques based on synchrotron radiation have been applied to environmental sciences giving the possibility for non-destructive investigations with micrometer spatial resolution. In particular, a combination of synchrotron methods (μ-XRF, μ-XRD, and μ-XAS) have been undertaken to investigate the metals speciation in mine wastes and soils. With this work, after a review on the mineralogical aspects of sulphide-rich waste-rock deposits and the application of synchrotron- based techniques for their characterization, we present a combined synchrotron-based μ-XRD, μ-XRF, and μ-XANES study to determine the mineralogy and the elemental distribution of metals in partially altered sulphide-mineralization fragments deposited within an open-air waste-rock dump (Libiola mine, eastern Liguria, Italy). The selected samples are composed of heterogeneous assemblages of Fe-bearing precipitates formed as a consequence of Fe-Cu sulphide alteration processes that occur within the main waste rock dump of the mining area. The results evidenced that the authigenic iron-rich phases generally contain signifi cant amounts of hazardous elements such as Cu, Zn, Mo, As, and Se. Moreover, a signifi cant mineralogical control on the mobility of these elements have been observed; in particular, the goethite-rich assemblages show high affi nity for Cu and Zn, whereas hematite-rich assemblages selectively concentrate As, Se, Mo, Cu and Zn.

abst R a C t Results of the investigation of paleontological blue and gray bone fragments of small vertebrates coming from stratigraphic layer 770 at San Josecito Cave (Nuevo Leon, Mexico, dating between 28 000 and 19 000 years BP), are presented. Structural and elemental analyses combining X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), and particle-induced X-ray and γ-ray emission (micro-PIXE/PIGE), as well as spectroscopic investigations [i.e., UV/visible/near-IR reflectance spectroscopy and X-ray absorption near-edge structure (XANES) spectroscopy] were performed to identify precisely the origin of the blue stain. Prior research has shown that Mn 5+ in tetrahedral coordination could be responsible for the turquoise blue color in mastodon ivory some tens of million years old that was modified by a heat process. Manganese is present in the anionic form of (MnO4) 3– and partially substitute for (PO4) 3– in the hydroxyapatite matrix. The spectroscopic data of the present study have revealed a heat-induced modification, revealed traces of Mn among the typical bone constituents (Ca, P, Sr, Zn), and provided insights into the color origin of the blue paleontological bones from San Josecito Cave. Cations of Mn 5+ in a tetrahedral environment of four O 2– ions in the apatite structure are found in these bones, the same color origin as in the blue mastodon ivory. As indicated by XANES, Mn 4+ ions in octahedral coordination as in pyrolusite are found in gray bones. The presence of submicroscopic Mn oxide inclusions might explain the color of the San Josecito gray bones. The formation of Mn 5+ very likely is induced by heat treatment of the bones under oxidizing conditions. The heat-induced modification of both types of paleontological bones also is indicated by the direct observation of apatite crystals using TEM. The question remains, however, how the heat originated inside the cave.

The formation of subsequent layers of calcium carbonate (CaCO3) in karst caves is a well-known phenomenon observed especially on the prehistoric paintings in the Large Cave (Grande Grotte) of Arcy-sur-Cure, in France. About 40 natural samples coming from the Large Cave were already investigated in a previous work and classified as a function of their crystal morphology, texture, composition and appearance. The presence of at least two calcite types was revealed on the walls: translucent and opaque white or grey calcites. The latter opaque calcites completely obstruct the paintings. The formation of these different calcites depends on various geochemical and geophysical parameters and could also be influenced by biotic processes. Questions remain about formation mechanisms leading to different calcite types and, in particular, about the role of micro-organisms as well as interactions between prehistoric paint layers and calcite layers. Additional natural calcites were studied in order to confirm the first classification. Various syntheses of abiotic calcite were performed to study the influence of environmental parameters on calcite growth. Moreover, several series of biotic calcite were synthesised in a specific medium with two bacteria isolated from the cave in order to test their calcifying properties. All natural and synthetic samples were analysed using complementary microanalytical laboratory techniques. Micro-x-ray fluorescence analysis (micro-XRF) and x-ray absorption near-edge structure spectroscopy (XANES) based on synchrotron radiation also enabled a more detailed distinguishing of different minerals within the complex biotic and abiotic mixtures and layered synthetic samples at microscopic scale. Comparison of natural and synthetic samples gives more detailed insights into the formation mechanisms of the different calcite types found in the Grande Grotte and allows proposing an adapted conservation strategy of its prehistoric paintings. Copyright © 2008 John Wiley & Sons, Ltd.

Manganese oxihydroxide behaviour has been studied under heat treatment to understand the transformation mechanisms and subsequently to gain insights into the preparation procedures of black painting materials during the Palaeolithic period. These manganese oxihydroxides have been studied as a function of heat treatment by TEM, XRD, DTA and FTIR and XANES (Mn K-edge) spectroscopies. These materials have been used as black pigments during the Palaeolithic period to realise rock art paintings such as in Lascaux (Dordogne, France) and Gargas (Midi-Pyre´ne´ es, France). Specific morphological, chemical and structural criteria were determined to distinguish between natural and heat-treated pigments.

This article demonstrates the possibility to perform X-ray diffraction/scattering computed tomography experiments with a laboratory diffraction setup. This technique is useful to characterize samples with inhomogeneities on a length scale of a couple of hundred micrometres. Furthermore, the method can be applied to preliminary phase-selective imaging prior to higher-resolution characterization using synchrotron radiation. This article presents the results of test experiments carried out on a rhombohedral C60sample previously studied at the ESRF.

This article aims to introduce the research presented in this volume of the Collection EDYTEM. The different papers come from a common scientific meeting between soil scientists of the French Soil Science Society (AFES) and organic geochemists of FROG. These articles seem to indicate a renewal of the approaches, issues and methods of study on the evolution of soil linked with human activities. Soil geochemistry and sediments (particularly organic geochemistry) appears as an indispensable tool to reveal the history of soil and human practices in the Anthropocene., Le présent article se propose de mettre en perspective les travaux de recherche présentés dans ce volume de la Collection EDYTEM. Fruit d’une rencontre scientifique entre pédologues de l’AFES et géochimistes de FROG, ces articles nous semblent témoigner d’un renouveau des approches, des questions et des méthodes d’étude sur l’évolution des sols en lien avec les activités humaines. La géochimie des sols et des sédiments (en particulier la géochimie organique) nous apparaît comme un outil indispensable pour révéler l’histoire des sols et des pratiques humaines à l’Anthropocène., Poulenard Jerôme, Arnaud Fabien, Perrette Yves, Sabatier Pierre, Deline Philip, Giguet-Covex Charline, Bajard Manon, Mourier Brice, Quiers Marine, Malet Emmanuel, Pignol Cécile, Develle Anne-Lise, Fanget Bernard, Dambrine Etienne, Faivre Pierre, Chalmin Emilie. Introduction. La géochimie organique des sols et des sédiments : une clé pour décrire l’anthropocène ?. In: Collection EDYTEM. Cahiers de géographie, numéro 18, 2015. Sols et matières organiques. Mémoires et héritages. pp. 9-18.

La scene naturaliste des « bisons adosses » de Lascaux, deja etudiee par les archeologues, pose la question de la conception d'une telle figure par les artistes magdaleniens. Afin de determiner les differents modes d'application, la nature des matieres picturales employees et leur mode de preparation, plusieurs prelevements ont ete etudies par microscopie electronique. Six prelevements, provenant de zones caracteristiques de ces deux bisons, nous permettent de reconstruire les gestes et de comprendre les intentions de ces hommes.

Analysis of archeological materials aims to rediscover the know-how of prehistoric men by determining the nature of the painting matter, its preparation mode, and the geographic origin of its raw materials. The preparation mode of the painting matter of the paleolithic rock art apparently consisted of mixing, grinding, and also heat-treatment.

Resume Le materiel necessaire a l'artiste-peintre prehistorique retrouve par l'Abbe Glory et la matiere picturale des « blasons » du panneau de la Vache Noire de la Nef ont ete etudies par microscopie electronique. Les resultats revelent d'une part, une utilisation de produits naturels sans adjonction de charge et, d'autre part, une grande diversite de matiere premiere, ce qui temoigne du souci des artistes pour la teinte et la texture des carreaux des blasons.

Analyses of archaeological materials attempt to rediscover the know-how of Prehistoric men by determining the nature of the matter, its preparation mode, and its geographic origin. The preparation mode of painting matter of Palaeolithic rock art consisted not only in mixing and grinding but also in heat-treatment. Palaeolithic painters used two main colors: red (iron oxide, hematite) and black (charcoal or manganese oxide). The different phases of manganese oxides can be distinguished using their elemental composition, their structure and the oxidation state of the Mn ion (II, III, IV). Their transformation during heat-treatment has been studied on mineralogical reference samples by means of transmission electron microscopy (TEM) either coupled or not with a heating stage (in situ). These studies have enabled us to understand the transformation mechanisms of manganese oxides and also to gain insights into the preparation procedures of painting materials during the Palaeolithic period. The painting samples studied in this paper come from the cave of Lascaux (Dordogne, France). These studies allow us to distinguish between natural or heat-treated manganese oxides.

International audience; Archaeologists have attempted the interpretation of rock art, but have often disregarded the technical aspects of paints. Analysing paint samples for preparation techniques and studying the various compounds used, allows us to determine the technology of early painters. Palaeolithic artists used two main colours: red (iron oxide: natural hematite or heated goethite) and black (charcoal or manganese oxides). These pigments could be prepared in different ways (grinding, mixing with extender and/or binder or by heating) in order to enhance the properties of the paints. Analyses attempt to determine the physicochemical nature of the matter and its preparation mode, and to get an idea of its geographic origin. This paper presents techniques and methods used in the C2RMF laboratory for manganese oxide pigments. Distinction between manganese oxides with or without other cations is made and heat treatment of manganese oxide minerals is described. Results obtained for black pigment in Lascaux and Ekain caves are presented and discussed. From paint analyses, several conclusions are drawn concerning the technical level of Palaeolithic artists.

International audience; Sulfur compounds are often present in petrochemical wastewater and can be detected by UV spectrophotometry. This technique allows to point out specific absorptions of mineral sulfide and mercaptans and can be used for the determination of acidity constants. From a quantitative point of view, using a spectral deconvolution method, a specific determination of some mercaptans is obtained. Detection limits for ethanethiol and thiophenol are 0.7 and 2.5 mg l−1, respectively.

International audience

Delannoy Jean-Jacques, Boche Élisa, Cailhol Didier, Couchoud Isabelle, Chalmin Emilie, Drysdale Russell, Duval-Massaloux Mélanie, Dzikowski Marc, Gauchon Christophe, Hobléa Fabien, Jaillet Stéphane, Lignier Vincent, Malgat Charlotte, Nehme Carole, Perrette Yves, Poulenard Jerôme, Quiers Marine, Sadier Benjamin. L'objet emblématique Karst. Paysages, mémoires de l'environnement et des hommes, dix années de recherches au laboratoire EDYTEM. In: Collection EDYTEM. Cahiers de géographie, numéro 16, 2014. Environnements, dynamiques et territoires de la montagne : Dix ans de recherches au laboratoire EDYTEM. pp. 51-84.

The colors of archaeomaterials provide important insights into ancient human activities, technologies, capabilities, symbols, and craftsmanship, making the study of color an important aspect of archaeological, art historical, and historical research. The color origins of archaeomaterials are usually related to major but also minor or trace elements, or minor components, in a particular chemical environment. However, the color can be changed over time due to alteration phenomena. Hence, the analysis of these archaeomaterials requires very sensitive and noninvasive methods. In addition to the direct measurement of color, other physicochemical methods, such as X-ray absorption spectroscopy, are well suited to study the colors in these archaeomaterials. Here, the authors present an overview of the methods most commonly used to study these materials. The pigments, paints, and minerals that are of particular importance in the study of cultural heritage are summarized and present a historical overview of the archaeometric study of such materials presented. In conclusion, several case studies are presented illustrating the potential of such studies to further inform our understanding of ancient human societies.

High-resolution manganese and iron K-edges XANES spectra were collected on several samples of archeological interest: prehistorical paintings and medieval glasses. XANES spectra were collected at the ID21 facility (ESRF, Grenoble, France) using a micro-beam device and at the 11-2 beamline (SSRL, Stanford, USA) using a submillimetric beam. The medieval glasses studied are from gothic glass windows from Normandy (XIVth century). The aim of this study is to help understand the chemical durability of these materials, exposed to weathering since the XIVth century. They are used as analogues of weathered glasses used to dump metallic wastes. These glasses show surficial enrichment in manganese, due to its oxidation from II (glass) to III/IV (surface), which precipitates as amorphous oxy-hydroxides. Similarly, iron is oxidized on the surface and forms ferrihydrite-type aggregates. The prehistorical paintings are from Lascaux and Ekain (Basque country). We choose in that study the black ones, rich in manganese to search for potential evidences of some 'savoir-faire' that the Paleolithic men could have used to realize their paint in rock art, as shown earlier for Fe-bearing pigments. A large number of highly valuable samples, micrometric scaled, were extracted from these frescoes and show large variation in the mineralogical nature ofmore » the black pigments used, from an amorphous psilomelane-type to a well-crystallized pyrolusite. Correlation with the crystals morphology helps understanding the know-how of these early artists.« less