Late Pleistocene/Early Holocene seafaring in the Aegean: new obsidian hydration dates with the SIMS-SS method

Archaeological evidence regarding the presence of obsidian in levels that antedate the food production stage could have been the result of usage or intrusion of small obsidian artifacts from overlying Neolithic layers. The new obsidian hydration dates presented below employing the novel SIMS-SS method, offers new results of absolute dating concordant with the excavation data. Our contribution sheds new light on the Late Pleistocene/Early Holocene exploitation of obsidian sources on the island of Melos in the Cyclades reporting dates c. 13th millennium - end of 10th millennium B.P.     

古代瓷器热释光测定年代制样方法的比较与研究

为了对古代瓷器热释光年代测定的两种不同制样方法——粉末法和薄片法的优劣进行比较,本工作从热释光灵敏度的均值标准偏差、三点回归的线性相关程度以及最后所测得年代与真值的符合情况等方面进行研究。研究结果表明,粉末法的测量精确度、准确度及可靠性均优于薄片法。粉末法可作为行业内制样标准参考。     

Archaeomagnetic research in the Andean highlands

Eleven archaeomagnetic samples were collected from several sites near Porco, Bolivia as part of the Proyecto Arqueológico Porco-Potosí. These samples were collected in order to 1) explore the availability of appropriate sample materials in the Bolivian Andes, and 2) assess the feasibility of pursuing reference curve research for this region. In addition, this research explored the archaeomagnetic dating application of reference curves constructed from the global geomagnetic field model gufm1 (Jackson et al., 2000), which covers the period from AD 1590–1990. This model is particularly applicable to our project, since many of the project sites are late prehispanic (pre-AD 1532) and early historic (ca. AD 1532–1825) in age. Of the 11 samples, three appeared to contain an insufficient amount of ferromagnetic minerals to provide reliable results, while eight samples produced acceptable-to-good results. The data from the eight good samples were compared to a reference curve for the period of AD 1600–2000 that was calculated for this project from the global field model, gufm1. The archaeomagnetic dates obtained for two of the samples agreed with archaeological expectations, while those for four other samples marginally or greatly postdated the archaeological age expectations. Two additional samples produced significantly different directions and could not be dated against the reference curve. It is likely that the age discrepancies for four of the samples stem from inaccuracies in the archaeomagnetic data, the archaeological age expectations, the calculated reference curve, or some combination of these factors.     

Cave occupations in Southeastern Arabia in the second millennium BCE: Excavation at Mugharat al-Kahf,North-Central Oman

This paper reports the results of excavation at Mugharat al-Kahf (WTN01) in Wādī Tanūf, North-central Oman. It also provides information on the nonmortuary and nonsedentary activities in central Oman during the Wādī Sūq period (2000–1600 BCE), as the subsistence and social arrangements of this period are the subject of much debate. Previous surveys had discovered a substantial amount of Wādī Sūq pottery at the site. This project took forward the excavation for further exploration. The excavation at Test Pit 1 identified Layers Ia and Ib, wherein pottery sherds, charred date stones and other samples for radiocarbon dating were discovered. These prove the cave's occupation during the early third millennium BCE, early second millennium BCE and the Islamic period. The analysis of artefacts and floral remains provided insights into the sojourn, storage and consumption of dates in the cave, and the mobile lifestyle in central Oman.     

上海青龙镇遗址出土瓷器和砖瓦样品热释光特性研究

利用热释光测定年代技术对青龙镇出土样品的烧造年代进行检测分析,以求帮助了解不同历史时期青龙镇瓷器贸易的发展状况。为此,本工作以青龙镇遗址出土瓷器中的67件瓷片及4件砖瓦样品为研究对象,用热释光前剂量饱和指数法测定瓷片样品古剂量;用热释光高温细颗粒技术测定砖瓦样品古剂量;用厚源α粒子计数法和X射线荧光光谱技术测量样品年剂量。瓷片样品热释光年代结果从唐代至南宋不等,砖瓦样品年代结果为北宋时期烧造,与文献记载中隆平寺塔的始建时间相符。     

Optically stimulated luminescence dating of the city wall system of ancient Tayma (NW Saudi Arabia)

In addition to a series of chronological markers (artefacts, pottery) in the archaeological contexts of ancient Tayma (NW Saudi Arabia), optically stimulated luminescence (OSL) and radiocarbon dating techniques were applied to generate reliable ages for the city wall system of the oasis. A massive aeolian sand deposit burying the oldest part of the outer wall of Tayma was sampled to obtain a minimum age for the construction of this wall. The sequence of OSL ages from the inactive dune (ID) (4900 ± 300 a, 5100 ± 400 a, 4400 ± 300 a, 3900 ± 200 a, 4000 ± 200 a) is in full accordance with ¹⁴C-AMS ages of charcoal embedded into the same dune (4190–4420 cal BP, 3870–4080 cal BP). Underlying alluvial samples from the inactive gravel sheet (IGS) in contrast give maximum ages for the construction which scatter between 6600 ± 300 a and 4900 ± 400 a. The new dating sequence provides evidence that the oldest part of the ancient city wall system already existed in the 2nd half of the 3rd mill. BC which is earlier than expected thus far from archaeological and architectural interpretation.     

A charcoal-rich horizon at Ø69, Greenland: evidence for vegetation burning during the Norse landnám?

It is often assumed that the colonisation of Greenland by Norse settlers in c. A.D. 985 had a sudden and dramatic effect on the environment, involving substantial vegetation clearance and environmental degradation. Consequently, it has been argued that charcoal-rich horizons, visible in many sections in Greenland, represent the initial burning of the vegetation by Norse farmers to create land suitable for agriculture. In this study a charcoal-rich layer, visible in a modern drainage ditch beside the Norse farm of Ø69, was analysed using archaeobotany, sedimentary analysis and radiocarbon dating to test the date and formation processes of the horizon. It is demonstrated that the charcoal-rich layer at Ø69 was not derived from in situ vegetation burning in the 10th century and concluded that the layer was probably formed by the addition of midden material to the infields around Ø69 in the 13th and 14th centuries cal AD, perhaps as part of a soil amendment strategy. It is argued that caution must be exercised when interpreting charcoal-rich horizons as time-specific chronological markers in palaeoenvironmental sequences in Greenland.     

Modelling site formation dynamics: geoarchaeological,chronometric and statistical approaches to a stratified rockshelter sequence,Polynesia

Formation processes and chronology are central to many archaeological endeavours, and accuracy in the latter is dependent on control of the former. Here we consider how to integrate geoarchaeological and chronometric evidence to better understand the formational history, along with the timing and duration of cultural activities, at a regionally significant site in the southern Cook Islands (Polynesia) which dates from ∼12th century AD. Initially we model natural and cultural processes of deposition using geoarchaeological evidence. The results are integrated with 21 radiocarbon dates, including nine new AMS results on identified medium and short-lived materials. Sample outliers are identified manually and statistically and a Bayesian analysis helps to refine age estimates for the site's 12 stratigraphic zones. The timing and rate of sediment accumulation is further considered through an age–depth model. Finally, the chronology developed from these combined approaches is used to address three key processes: 1) initial site use, potentially relevant to human colonisation of this Polynesian island and archipelago; 2) on-site activities and patterns of resource use; and 3) major marine deposition events which disrupted cultural activities and may have palaeoclimatological significance. The approach developed here potentially has utility elsewhere, particularly where human activities are recurrent and of limited duration.     

Seasonal dating and the valve-pairing technique in shell-midden analysis

Three-dimensional excavation of 23 artifact fragments and 4382 shells was carried out in the shell layer of an abandoned dwelling pit. Principal component analysis using three locational variables was used for drawing the central axes and the regression plane of the shell layer. Valve-pairing carried out on the clam Meretrix lusoria indicated that 380 pairs could be established among a total of 2089 unbroken valves. Preservation of shells was estimated at 70% by comparing the number of shells found in the shell layer with the clam population size which was in turn calculated by a probability formula using paired valves among samples. In addition to these data, the distance separating pairs gave some idea of the movement of shells. Seasonal dating by daily growth line counting showed that the shell layer could be subdivided into at least three main seasonal layers and that the period of accumulation was approximately 500 days.     

Growth of the Lichen Buellia albula and its Potential for Lichenometric Dating in South‐eastern Australia

Lichenometric dating is a cheap, relatively rapid means of dating rock surfaces, which has generally been overlooked in Australia. While lichenometry finds its greatest application in arctic and alpine geomorphological studies, there has been limited application to archaeological studies. This project set out to test the technique in south‐eastern Australia, and assess its usefulness for dating post‐settlement artefacts. The diameters of Buellia albula lichens growing on well‐dated memorials in the Bendigo cemetery were measured, and the relationship between age and lichen diameter established. The results indicate that B. albula can be used to determine the age of exposed cement surfaces from the 1890s to the present. The positive results suggest the technique should be investigated in other applications and environments in Australia, particularly where alternative dating techniques cannot be used.