A new Palaeolithic discovery: tar-hafted stone tools in a European Mid-Pleistocene bone-bearing bed

Two stone flakes partly covered in birch-bark-tar and a third without tar on it were discovered in fluvial gravel and clay in central Italy, in association with the bones of a young adult female Elephas (Palaeoloxondon) antiquus and several micromammals. The probable chronology of the stone flakes is compatible with the late Middle Pleistocene suggested by the site's small mammals and geological context. The fauna indicates a cool stadial episode before isotope stage 6. That age means the flakes are the oldest ever found hafted with tar and indicate a greater capacity for late Middle Pleistocene hominins to utilize raw materials available during cold phases.     

Fracture-fill calcite as a record of microbial methanogenesis and fluid migration: a case study from the Devonian Antrim Shale, Michigan Basin

The Devonian Antrim Shale is an organic‐rich, naturally fractured black shale in the Michigan Basin that serves as both a source and reservoir for natural gas. A well‐developed network of major, through‐going vertical fractures controls reservoir‐scale permeability in the Antrim Shale. Many fractures are open, but some are partially sealed by calcite cements that retain isotopic evidence of widespread microbial methanogenesis. Fracture filling calcite displays an unusually broad spectrum of δ¹³C values (+34 to ?41‰ PDB), suggesting that both aerobic and anaerobic bacterial processes were active in the reservoir. Calcites with high δ¹³C values (>+15‰) record cementation of fractures from dissolved inorganic carbon (DIC) generated during bacterial methanogenesis. Calcites with low δ¹³C values (13C values between ?10 and ?30‰ can be attributed to variable organic matter oxidation pathways, methane oxidation, and carbonate rock buffering. Identification of ¹³C‐rich calcite provides unambiguous evidence of biogenic methane generation and may be used to identify gas deposits in other sedimentary basins. It is likely that repeated glacial advances and retreats exposed the Antrim Shale at the basin margin, enhanced meteoric recharge into the shallow part of the fractured reservoir, and initiated multiple episodes of bacterial methanogenesis and methanotrophic activity that were recorded in fracture‐fill cements. The δ¹⁸O values in both formation waters and calcite cements increase with depth in the basin (?12 to ?4‰ SMOW, and +21 to +27‰ PDB, respectively). Most fracture‐fill cements from outcrop samples have δ¹³C values between ?41 and ?15‰ PDB. In contrast, most cement in cores have δ¹³C values between +15 and +34‰ PDB. Radiocarbon and ²³⁰Th dating of fracture‐fill calcite indicates that the calcite formed between 33 and 390 ka, well within the Pleistocene Epoch.     

Common ware production at Thamusida: dating and characterisation of Roman and Islamic pottery

Twenty-one samples of likely Roman, likely Islamic and unknown common ware from the archaeological site of Thamusida (Rabat, Morocco) were analysed in order to anchor selected types of pottery to a limited time span and, possibly, to a production area and technology. Analytical techniques were thermoluminescence, optical microscopy, scanning electron microscopy and X-ray fluorescence. The results arising from this research are definitely useful for the study of the site of Thamusida as well as for all researchers involved in archaeological and archaeometrical research in Morocco. Chronologies proposed on a typological base have been denied twice: a likely Islamic cup dates back to the second century a.d.; vice versa, a stewpot, framed into the Roman period, resulted to be an eighth century a.d. production. Moreover, the identification of an eighteenth century ceramic production is of outstanding importance, as it characterises a completely unknown production. Regarding the production area, four samples of both Roman and Islamic periods have been recognised as local productions of Thamusida.     

The French moment of the American national identity. St. John de Crèvecoeur's agrarian myth

The aim of this essay is to return to the genesis of the American agrarian myth in the eighteenth century, as a path to investigate the origins of the American national identity. This will be done by means of a comprehensive reassessment of St. John de Crèvecoeur, the Norman noble whose name is bound to the success of Letters from an American Farmer. His work contains the origins of the agrarian ideal as a peculiarly American phenomenon, prior to independence and before Republican ideology placed agrarian democracy at its foundations, making the project of agrarian development and democratic participation inseparable one from another. A Frenchman who became American and then, after 25 years, French again, Crèvecoeur represents an ideal lens through which to analyse the hitherto insufficiently explored contribution of French economic culture to the creation of American national identity. As a multi-faceted figure whose richness has been dominated by his image as the author of a best-selling autobiographical novel, Crèvecoeur is here also seen (partly through unpublished sources) as an agronomist who was no stranger to physiocracy and as a diplomat and French intellectual who always felt profoundly American. It was precisely this attachment to the land, seen as fundamental to the vision of a new and distinct form of peaceful cohabitation and democratic partnership, that became a political theme and an economic development project of the new nation and, as such, was a main plank of the agrarian ideology of Thomas Jefferson's Republicans.     

The study of pitch via gas chromatography–mass spectrometry and Fourier-transformed infrared spectroscopy: the case of the Roman amphoras from Monte Poro,Calabria (Italy)

The analysis of the composition of organic residues present in ancient pottery are an important source of information for archaeologists. The chemical characterisation of these materials gives information on diets, habits, technologies and original use of the vessels.     

Prehistoric land use at an archaeological hot-spot (the rock art park of Campo Lameiro,NW Spain) inferred from charcoal,synanthropic pollen and non-pollen palynomorph proxies

Pollen, non-pollen palynomorphs and charcoal from a colluvial soil surrounded by prehistoric petroglyphs (Campo Lameiro, NW Spain) were studied in order to assess the nature of human activities and their impact on Holocene vegetation patterns. Several phases of anthropogenic impact were observed. (i) Between 7.6 and 6.5 ka cal BP, synanthropic taxa (Urtica dioica type, Plantago lanceolata type) and coprophilous fungi (e.g. Sporormiella-type) are indicative of early (pre-agricultural) creation of small patches of pasture using fire, possibly for incipient animal husbandry or as part of a deliberate strategy to improve game availability. Such activities only had a minor effect on the deciduous Quercus-dominated forest established earlier during the Holocene Thermal Maximum. (ii) Between 5.9 and 4.8 ka cal BP a more intense signal indicative of pastoral activity was detected, corresponding to the Neolithic period. (iii) Between 4.8 and 3.4 ka cal BP, which fits within the hypothetical timeframe of petroglyph creation, the synanthropic and humidity (e.g. Cyperaceae, Mougeotia) indicators diminished while charcoal concentration increased, which can be explained by Mid-Holocene cooling/drying (Neoglaciation) in combination with reduced human impact, or by non-pastoral activities in the area possibly in association with the development of the rock art culture, converting pasture to protected open ground through anthropogenic fires. (iv) During the Late Bronze Age and Early Iron Age (3.4–2.5 ka cal BP), grazing pressure and fire regime intensity are high, coinciding with evidence of regional forest regression, despite an amelioration in climate. (v) Later phases, not corresponding to prehistoric rock art contexts, include a phase of heavy grazing and reduced fire frequency (from ca. 2.5 to 1.2 ka cal BP) as well as the near complete elimination of the deciduous woodland, the expansion of ericaceous shrubland and the evidence of local agriculture and afforestation. These results are consistent with earlier studies in the area and highlight the spatial heterogeneity in the vegetation especially during periods of prehistoric anthropogenic interference.