RADIOCARBON DATES FOR BEESWAX FIGURES IN THE PREHISTORIC ROCK ART OF NORTHERN AUSTRALIA

Accelerator mass spectrometry radiocarbon ages have been taken for a test suite of small samples of material removed from some of the ‘beeswax’art figures found in rock shelters in northern Australia. The results indicate that we can reliably date this unique form of rock art with no noticeable damage. We had not expected to find figures of any great antiquity, and so we were surprised to find that the ages obtained spanned the time period from the recent past to about 4000 BP.     

A NEW DIRECT RADIOCARBON AMS DATE FOR AN UPPER PALAEOLITHIC HUMAN BONE FROM SIBERIA

A new AMS radiocarbon date has been obtained from a Siberian human bone sample taken directly from a cranial fragment. The specimen comes from the north‐east Siberian site of Pokrovka 2 (55⁰19′46.30″N, 92⁰26′48.80″E). The remains consist of the anterior portion of the cranium or the superior part of the face; that is, the forehead and the roof of the eye sockets. Sadly, indifferent features of the frontal bone do not allow a confident diagnosis of the sex of the individual. The evidence suggests, however, that the remains are probably those of a young adult (teenager) and an anatomically modern human, rather than a Neanderthal. Radiocarbon dating was undertaken at the Oxford Radiocarbon Accelerator Unit (ORAU). The radiocarbon age determination of the bone fragment, 27 740 ± 150 bp (OxA‐19850), is one of the earliest direct dates for a modern human from Siberia. The Pokrovka cranial fragment dates to the middle Upper Palaeolithic of Eurasia and is broadly contemporary with the human remains from the famous eastern European site of Sunghir. When the radiocarbon age is compared with the Cariaco Basin ¹⁴C data set and the Greenland oxygen isotope record of NGRIP, it corresponds with Greenland Interstadial 5, a warmer phase of the Last Glacial period, although this is a preliminary conclusion, and is based on climate records that may or may not be wholly synchronous between the two locations.     

OPTICAL DATING OF SINGLE AND MULTIPLE GRAINS OF QUARTZ FROM JINMIUM ROCK SHELTER,NORTHERN AUSTRALIA: PART II,RESULTS AND IMPLICATIONS*

Quartz sediments from the floor deposit at Jinmium rock shelter have been investigated using the multiple-grain and single-grain optical dating methods described by Galbraith et al. (1999, this volume). Here we present the results of this dating programme and argue that the artefact-bearing sediments were deposited within the last 10000 years. This time interval is consistent with the radiocarbon chronology but is much younger than previous claims for initial human occupation during the Pleistocene. Analysis of individual grains revealed also that the characteristic saturation doses of some grains are unusually high, which may permit dating of deposits older than a few hundred thousand years. Such grain-to-grain differences raise doubts, however, about the validity of using multiple-grain samples to investigate the phenomenology of quartz luminescence.     

OPTICAL DATING OF SINGLE AND MULTIPLE GRAINS OF QUARTZ FROM JINMIUM ROCK SHELTER,NORTHERN AUSTRALIA: PART I,EXPERIMENTAL DESIGN AND STATISTICAL MODELS*

Jinmium rock shelter is famous for the claims made by Fullagar et al. (1996) for the early human colonization and ancient rock art of northern Australia. These claims were based on thermo-luminescence ages obtained for the artefact-bearing quartz sediments that form the floor deposit at the site. In this paper, we outline the background to the optical dating programme at Jinmium, and describe the experimental design and statistical methods used to obtain optical ages from single grains of quartz sand. The results, interpretations, and implications of this dating programme are reported in a companion paper (Roberts et al. 7999, this volume).     

THE CHRONOSTRATIGRAPHY AND GEOARCHAEOLOGICAL SIGNIFICANCE OF AN ALLUVIAL GEOARCHIVE: COMPARATIVE OSL AND AMS 14C DATING FROM GREECE*

The Basin of Phlious in southern Greece is known for its thick colluvial and alluvial deposits from the Holocene. It offers a good opportunity to reconstruct the history of Holocene soil erosion and its interaction with historical farming activities. In this study, we present new results based on optically stimulated luminescence (OSL) dating from the Basin of Phlious. The comparison between OSL and ¹⁴C AMS ages shows good agreement, and demonstrates the need for the detection of insufficiently bleached OSL samples in order to obtain accurate results. The discovery of a Neolithic site, buried under thick alluvial deposits, confirms the hitherto postulated Neolithic human impact on the landscape.     

ROCK SURFACE HARDNESS AS AN INDICATION OF EXPOSURE AGE: AN ARCHAEOLOGICAL APPLICATION OF THE SCHMIDT HAMMER*

A Schmidt Hammer was employed in evaluating the surface hardness of rocks which line ancient anthropogenic pit features, known as Pukaskwa pits, on the north shore of Lake Superior, Canada. This technique offers a possible new method of producing relative ana absolute dates for such exposed stone features Analysis of the data has provided a relative chronology for the pit features, representing two distinct construction phases. The range of absolute dates generated from the data indicates that the pits were likely constructed by Blackduck peoples c. 900 to 400 years BP.