陕西志丹县马头山道教真身泥塑年代的测定分析

14C测年技术作为一种测年技术已广泛地应用在考古学、地质年代学、古气候学、古地理学等许多方面。为了解陕西志丹县马头山道教真身泥塑的年代,采用加速器质谱14C技术对道教真身泥塑的谷秸进行了测试,测试结果表明该真身泥塑制作年代在17世纪中叶至18世纪末的可能性较大。     

精确定年的祁连圆柏碳十四年代的加速器质谱测定

前言 1949年,碳十四断代的创始人利比(W.F.Libby)公布了第一批碳十四年代数据,宣告碳十四测年方法取得成功,轰动了整个考古界和地质学界。碳十四     

Environmental impacts around the time of Norse landnám in the Qorlortoq valley,Eastern Settlement,Greenland

Palynology, radiocarbon dating, and open-section stratigraphies from archaeological trenches are used to examine the impact of human activity around the time of Norse landnám on vegetation and landscape associated with a small farm (Ø34) in the Qorlortoq valley, Eastern Settlement, Greenland (61° N 45° W). Peat deposits from a mire abutting the Norse ruins revealed a discontinuous palaeoenvironmental record containing a possible hiatus from ca. AD 410–1020. Palaeovegetational data were recovered either side of this period. Pollen assemblages suggest that open Salix scrub dominated the landscape during the pre-settlement phase. The later phases of landnám resulted in the creation of hay fields and heavily-grazed grassy heath. Site abandonment is reflected by a re-expansion of Salix. This occurs shortly before the onset of deposition of a Sphagnum peat, dated to cal AD 1420–1630 (2σ) and reflecting an increase in mire surface wetness, probably in response to a deteriorating climate. Radiocarbon dates were obtained on peat and plant macrofossils sampled from either side of the proposed hiatus at two different but closely-spaced (<20 m) locations across the mire. These produced significantly different dates for the cessation of peat formation in the pre-landnám period (cal BC 2130–1770 and cal AD 240–410 respectively), but near-synchronous dates for the recommencement of peat growth (cal AD 890–1150 for peat and a probably more reliable interval of cal AD 1020–1190 based on plant macrofossils). It is suggested that this hiatus may represent the first direct evidence for peat cutting in Norse Greenland.     

前剂量饱和指数法测定瓷器的热释光年代

用前剂量饱和指数法测定39件历代瓷器的热释光年代。结果表明,热释光年代与考古年代在一个标准偏差(±1σ)为29％以内的一致性非常良好。这样的误差在瓷器年代测定中是可以接受的。     

The application of luminescence dating in American archaeology

Luminescence dating is underutilized in American archaeology given the theoretical advantages of direct dating that it confers. Recent advances in understanding the physical processes underlying the method have also made it more reliable as a dating tool. This research as well as potential applications is reviewed.     

The Baptistry of Saint John in Florence: The Scientific Dating of the Timber Structure of the Dome

The construction of the Baptistry of Saint John has a debated and uncertain history; the hypothesis on its main construction phases may span from the Roman period to the 13th century, according to different authors. This uncertainty is mainly due to the lack of primary sources and certain dating issues. By combining dendrochronological analysis and radiocarbon dating, some light was shed on the building’s history. Open at least from 897, in 1059 Pope Nicholas II re-consecrated the baptistry after several renovations. Around that period, the octagonal dome was probably built by using chestnut beams to tie the structure together. The dendrochronological analysis dated the silver fir element to 1268. This element possibly represents a replacement coincident with the period, between 1270 and 1300, when a substantial part of the mosaics of the dome was positioned.     

Two Ancient Wooden Anchors from Ein Gedi, on the Dead Sea, Israel

Two ancient wooden anchors with ropes, dating to different periods, were found on the western shore of the Dead Sea. The one-armed anchor was dated by 14C to the Late Iron Age—Persian Period, and the second anchor to the Roman Period. The saline water of the Dead Sea preserved the wood and ropes, but corroded almost all the metal parts. A thin black crust of lead and a green crust of copper are the only remains of the collar of the Roman anchor. The finds were made from local tree species and were probably made locally: the one-armed anchor from Acacia, the Roman one from Christ-thorn, and both ropes of date-palm.
© 2005 The Nautical Archaeology Society     

Direct radiocarbon (AMS) dating of split-based points from the (Proto)Aurignacian of Trou de la Mère Clochette,Northeastern France. Implications for the characterization of the Aurignacian and the timing of technical innovations in Europe

Radiocarbon (AMS) dates on two split-based point wings and a hominin molar from the site of Trou de la Mère Clochette in the French Jura are presented in this paper. Dating split-based points has very rarely been undertaken. This is unfortunate given that these artefacts are critical to our definition and characterization of Early Upper Palaeolithic technocomplexes, as they are considered to be the type fossil of the Classic Aurignacian.     

Copper production at Baratti (Populonia,southern Tuscany) in the early Etruscan period (9th–8th centuries BC)

Populonia is commonly regarded as one of the most important iron working centres in Europe in the 1st millennium BC. However, multiple layers of copper slags have been recently discovered at the bottom of the slag deposit occurring along the shoreline of the underlying Baratti Gulf. Copper slag layers have been radiocarbon dated to the 9th–8th centuries BC, i.e. to an early metallurgical stage predating the later large-scale iron production. The overall features of copper slags indicate a single-step smelting process of copper-rich ores containing variable amounts of Zn and Pb. Chemical and textural features of copper slags indicate an optimised, high-efficiency metallurgical process.     

Possible isotopic fractionation of argon in source obsidians and archeological artifacts from Kulkuletti, Ethiopia

Despite uniform geochemistry ⁴⁰Ar/³⁹Ar ages of 0.6, 1.25, and 1.3 Ma on obsidians from a source flow (Worja) and from archeological artifacts at the sites of Kulkuletti (near Gademotta, Ethiopia) have been interpreted to suggest that they derive from different source flows of different ages. A further suggestion is that the magmatic source of the obsidian flows was chemically homogeneous between 1.3 Ma and 0.6 Ma. Chemical analysis of these obsidians indeed suggests that they derive from a single flow. Reexamination of the argon isotopic data reveals that argon isotopes may have been fractionated within the flow, so that the assumption of an atmospheric ⁴⁰Ar/³⁶Ar ratio of 295.5 is inappropriate to use for computing ages. Three groups of data are apparent, and internally all yield ages near 1.3 Ma if the intercept value for ⁴⁰Ar/³⁶Ar from an isotope correlation plot is used for computation instead of using the atmospheric ratio. The Soret thermal diffusion effect provides a possible mechanism of fractionation of argon within the obsidian flow that is of approximately the right magnitude to explain the observations by in-diffusion of already fractionated atmospheric argon.