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Using a conventional, off-the-shelf digital single lens reflex camera and flashes, we were able to create high-resolution panoramas of stratigraphic profiles ranging from a single meter to over 5 m in both height and width at the Middle Stone Age site of PP5-6 at Pinnacle Point, Mossel Bay, South Africa. The final photomosaics are isoluminant, rectilinear, and have a pixel spatial resolution of 1 mm. Furthermore, we systematically color-corrected the raw imagery. This process standardized the colors seen across the photomosaics while also creating reproducible and meaningful colors for relative colorimetric analysis between photomosiacs. Here, we provide a detailed discussion about the creation and application of our photomosaics. In the first part of the paper, we examine the specific characteristics of modern digital single lens reflex (DSLR) cameras and lenses that were important to us in developing our methodology. We also provide a detailed discussion about how to reproduce the methodology in the field and to post-process the imagery. In the final section of the paper, we give several examples to show how we apply our photomosaics within an empirical 3D GIS database. These examples are provided to show how photographic data can be integrated with other digitally-captured data and used to study the relationships between the stratigraphic features seen in the photomosaics and the 3D distribution of excavated archaeological piece-plots, geochronological samples, and other kinds of geological samples. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents new chronological data applied to the problem of providing a date for the construction of a prehistoric building, with a case study from the Old Scatness Broch, Shetland. The innovative methodology employed utilises the combination of radiocarbon and optically stimulated luminescence (OSL) dates with the archaeological information, which includes the stratigraphic relationships of sampled deposits, context information, and evidence relating to the formation of the deposit. This paper discusses the scientific validity of the dates produced, and the advantages that the methodology employed at this site offers for archaeological interpretation. The combined dating evidence suggests that the broch at Old Scatness is earlier than the conventionally accepted dates for broch construction. More broadly it shows the value of integration of the specialists at the planning stages of the excavation. The application of a Bayesian statistical model to the sequences of dates allowed investigation of the robustness of the dates within the stratigraphic sequences, as well as increasing the resolution of the resulting chronology. In addition, the value of utilising multiple dating techniques on the same deposit was demonstrated, as this allowed different dated events to be directly compared as well as issues relating to the formation of the sampled deposit. This in turn impacted on the chronological significance of the resulting dating evidence, and therefore the confidence that could be placed in the results. [ABSTRACT FROM AUTHOR]

The Southern Montane Forest-Grassland mosaic ecosystem in the humid subtropics southern Rift Valley of Africa comprised the environmental context for a large area in which modern human evolution and dispersal occurred. Variable climatic conditions during the Late Pleistocene have ranged between humid and hyperarid, changing the character of the ecosystem and transforming it at different points in time into a barrier, a refuge, and a corridor between southern and eastern African populations. Alluvial fans presently blanket the areas adjacent to major river systems, which were key areas of prehistoric human habitation. These sets of variables have created conditions that are both challenging and advantageous to conduct archaeological research. Lateritic soil development has resulted in poor organic preservation and facilitated insect bioturbation, which has demanded an integrated micro-macro scale approach to building a reliable geochronology. An integrated field and analytical methodology has also been employed to identify the nature and degree of post-depositional movement in alluvial deposits, which preserve a wide range of spatial integrity levels in buried stone artifact assemblages between 47 and 30 ka in Karonga, northern Malawi. This paper describes the methodological advances taken toward understanding open-air Middle Stone Age archaeology in sub-tropical Africa, and explores the inferential potential for understanding Pleistocene human ecology in the important southern Rift Valley region. [ABSTRACT FROM AUTHOR]

In this paper we generate chronological constraints through optically stimulated luminescence (OSL) dating on extensive prehistoric stone structures that stretch out in the Arabian Desert and appear as geometric lines, known as the “Works of the Old Men”. Two major types of the “Works” that are common throughout the Arabian Desert are the “wheels” and the more intensively investigated “desert kites”. Here, OSL dating was applied to “wheels” in the Wadi Wisad area, in the eastern badia of Jordan. OSL dating generated ages that fall into the Late Neolithic to Chalcolithic and Early Bronze Age periods. This chronological spectrum is consistent with the well-documented prehistoric activities at the archaeological site of Wisad Pools, also located in the Wadi Wisad area. Spatial analyses of the “Works” in Wadi Wisad and in the Azraq Oasis revealed that: 1) the wheels are organized in clusters, 2) the spatial distribution of the wheels is predetermined by the kites, 3) the kites were most probably created earlier than the wheels in the study areas and 4) a cluster of wheels nearby the Azraq Oasis tentatively demonstrates ranking and, perhaps, tendency for alignment, although this is not the case for the other wheel-clusters studied. Despite the progress toward understanding the chronological and spatial aspects of the wheels, a great deal of research remains to resolve the actual nature of these enigmatic stone structures. [ABSTRACT FROM AUTHOR]

In this paper we present a time-stratigraphic scheme and geologic time scale for the protoplanet Vesta, based on global geologic mapping and other analyses of NASA Dawn spacecraft data, complemented by insights gained from laboratory studies of howardite–eucrite–diogenite (HED) meteorites and geophysical modeling. On the basis of prominent impact structures and their associated deposits, we propose a time scale for Vesta that consists of four geologic time periods: Pre-Veneneian, Veneneian, Rheasilvian, and Marcian. The Pre-Veneneian Period covers the time from the formation of Vesta up to the Veneneia impact event, from 4.6 Ga to >2.1 Ga (using the asteroid flux-derived chronology system) or from 4.6 Ga to 3.7 Ga (under the lunar-derived chronology system). The Veneneian Period covers the time span between the Veneneia and Rheasilvia impact events, from >2.1 to 1 Ga (asteroid flux-derived chronology) or from 3.7 to 3.5 Ga (lunar-derived chronology), respectively. The Rheasilvian Period covers the time span between the Rheasilvia and Marcia impact events, and the Marcian Period covers the time between the Marcia impact event until the present. The age of the Marcia impact is still uncertain, but our current best estimates from crater counts of the ejecta blanket suggest an age between ∼120 and 390 Ma, depending upon choice of chronology system used. Regardless, the Marcia impact represents the youngest major geologic event on Vesta. Our proposed four-period geologic time scale for Vesta is, to a first order, comparable to those developed for other airless terrestrial bodies. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a new series of AMS dates on ultrafiltered bone gelatin extracted from identified cutmarked or humanly-modified bones and teeth from the site of Abri Pataud, in the French Dordogne. The sequence of 32 new determinations provides a coherent and reliable chronology from the site’s early Upper Palaeolithic levels 5–14, excavated by Hallam Movius. The results show that there were some problems with the previous series of dates, with many underestimating the real age. The new results, when calibrated and modelled using a Bayesian statistical method, allow detailed understanding of the pace of cultural changes within the Aurignacian I and II levels of the site, something not achievable before. In the future, the sequence of dates will allow wider comparison to similarly dated contexts elsewhere in Europe. High precision dating is only possible by using large suites of AMS dates from humanly-modified material within well understood archaeological sequences modelled using a Bayesian statistical method. [Copyright &y& Elsevier]

Abstract: A robust timeframe for the extant cave deposits at Liang Bua, and for the river terraces in the adjoining Wae Racang valley, is essential to constrain the period of existence and time of extinction of Homo floresiensis and other biota that have been excavated at this hominin type locality. Reliable age control is also required for the variety of artifacts excavated from these deposits, and to assist in environmental reconstructions for this river valley and for the region more broadly. In this paper, we summarize the available geochronological information for Liang Bua and its immediate environs, obtained using seven numerical-age methods: radiocarbon, thermoluminescence, optically- and infrared-stimulated luminescence (collectively known as optical dating), uranium-series, electron spin resonance, and coupled electron spin resonance/uranium-series. We synthesize the large number of numerical age determinations reported previously and present additional age estimates germane to questions of hominin evolution and extinction. [Copyright &y& Elsevier]

Abstract: The Middle Son valley in north-central India preserves extensive Quaternary alluvial deposits. A long history of archaeological and geological research in the valley has resulted in the discovery of lithic assemblages ranging from Lower Palaeolithic to microlithic, a rich corpus of fossilised faunal remains, and ash deposits from the ∼74,000year-old Toba supereruption. This paper reviews the chronology and stratigraphy of the valley’s Quaternary sediments, and presents a model that hypothesizes the temporal sequence of important lithic assemblages from excavated and surface contexts. Artefacts in these assemblages are analysed and changes in lithic technology through time are described; this evidence is used to propose shifts in hominin behaviour and demographic structure in this region during the Upper Pleistocene. Recognising gaps in our understanding of the Middle Son record, future avenues of research are recommended that will build upon previous research and address questions of palaeoanthropological significance. The Middle Son valley preserves a long and rich record of hominin occupation from all periods of the Palaeolithic that is rarely paralleled by other sites in India. [Copyright &y& Elsevier]

Abstract: In this paper, we describe a new species of Hemiacodon known only from University of Colorado Museum Loc. 92189 (Donna''s Locality) in the Turtle Bluff Member of the Bridger Formation, Green River Basin, southwestern Wyoming. Donna''s locality has yielded a diverse mostly small-bodied mammalian assemblage of Bridgerian and first appearance Uintan mammalian taxa, as well as range-through taxa. Together with H. engardae sp. nov., the faunal assemblage from Donna''s Locality and more recently discovered localities in the same stratigraphic interval provides the first conclusive paleontological evidence of an earliest Uintan age (Ui1A biochron) for the Turtle Bluff Member of the Bridger Formation. The new species is represented by a sample of 11 specimens consisting of well-preserved upper and lower premolars and lower molars. H. engardae is distinct from H. gracilis on the basis of overall larger size as well as a combination of features of the premolars and molars related to a greater development of shearing crests. This suggests that H. engardae may have incorporated more foliage into its diet than the Bridgerian species, H. gracilis. [Copyright &y& Elsevier]