Luminescence Dating of Monumental Stone Architecture at Chavín De Huántar,Perú

Optically stimulated luminescence (OSL) is applied to quartz extracted from mud mortar collected from Chavín de Huántar, an early Andean monumental center. The samples appear to have been only partially exposed to sunlight during construction, so a minimum age model is applied to equivalent dose distributions. Complications, including complex radioactivity, low sensitivity of the quartz, and limited sample, prevent high precision, but the 14 dates obtained cluster around 1000 BC largely in agreement with radiocarbon assays on charcoal also collected from the mortar. Results suggest a relatively rapid construction for the monument. This work develops OSL as a method for directly dating architectural mortar.     

古陶瓷科学技术研究在科技考古中的三例应用

利用多元统计分析方法研究了从杭州古中河南段采集的月白釉瓷片,浙江临安天目山地区发现的黑釉瓷片和景德镇历代青花瓷片的胎、釉化学组成和青花色料的变化规律。从而讨论了杭州古中河南段采集的瓷片可能就是凤凰山下万松林附近的修内司官窑制品;指山临安天目山地区新发现的窑群和黑釉瓷才是名副其实的天目窑和天目瓷;发现了元代以及明初洪武和永乐朝青花瓷所用的料可能是来自西域的进口料,而宣德青花瓷所用的色料多数可能是国产的粘土矿。     

西沙群岛“石屿二号”沉船遗址出水青花瓷器的测年研究

“石屿二号”沉船遗址位于西沙群岛石屿东侧的珊瑚礁石上,是西沙群岛海域一处重要水下文化遗存。该遗址出水了青花、卵白釉、白釉、青灰釉、酱釉等多种瓷器,是探索古代海上丝绸之路和外销瓷贸易的关键窗口。虽然前人通过青花瓷器类型学分析确定了遗址的相对年代,但由于未发现船体痕迹无法进行碳十四测年,而热释光测年方法则为确定遗址的绝对年代提供了一种替代手段。为了探究该遗址出水青花瓷器的热释光性质及年代,本研究利用前剂量饱和指数法对16件青花瓷片进行了古剂量测试。使用电感耦合等离子体质谱仪(ICP-MS)和电感耦合等离子体发射光谱仪(ICP-OES)分析样品的放射性元素U、Th、⁴⁰K的含量。在剂量率的计算过程中综合考虑了样品的经纬度、埋藏深度、含水率以及放射性元素含量等参数,并首次使用综合矿物分析(TIMA)揭示了瓷胎中的石英粒径分布情况,以提高剂量率计算的准确度。热释光年代结果表明,这批青花瓷烧制于元代至明代早期,在释光有限的误差范围内符合传统鉴定方法得出的该遗址属于元代这一结论。这有助于揭示该历史时期相关器物的制作工艺、实际用途和可能的产地。此外,这也为理解该历史时期青花瓷器在...     

瓷器热释光测定年代研究

本工作从标准的(即线性的)前剂量技术着手,研究了瓷器热释光测定年代的方法。在这个研究中,发现了瓷器的灵敏度对剂量的非线性响应和灵敏度随剂量变化的指数模式。因此,一个用饱和指数拟合的方法被提了出来。实验表明,这是一个测定瓷器年代的成功方法。另外,还对一些与测定年代有关的复杂因素进行了讨论。例如,当少数瓷器的灵敏度与剂量不呈指数关系时,就要改变拟合模式或采用B的平均值方法等。     

原始瓷的三种年代测定方法结果比较

采用常规的热释光细粒混合矿物法、热释光前剂量饱和指数法以及单片再生剂量光释光法三种测年方法,对中国上海、浙江萧山地区出土的7件西周、春秋、战国以及汉代的原始瓷样品进行了年代测定,并对测得的每个样品的3个年代结果与已知年代进行比对。用热释光细粒混合矿物法测定得到了较为理想的年代结果,与样品的已知年代结果相比吻合得较好。用热释光前剂量饱和指数法测定得到了该方法的上限饱和年代,即距今1800年左右。用再生剂量光释光法测定得到了这些样品的年代,只是实际年代的50％-80％左右,结果不太理想。因此,采用热释光细粒混合矿物法测定这类样品的年代,只要解决了制样问题,还是目前较好的测年方法。     

A note on the use of temporal frequency distributions in studies of prehistoric demography

Temporal frequency distributions of archaeological sites and radiocarbon dates are commonly used as proxies for prehistoric population levels based on the assumption that more people create a stronger archaeological signal. While this assumption is certainly correct, we question whether relative frequencies of sites or dates observed from prehistoric contexts are necessarily linked to human demography. In this paper, we demonstrate that the typical positive curvilinear frequency distributions observed in archaeological contexts also regularly occur in paleontological and geological contexts and are thus likely caused by the operation of time-dependent destructive processes, what we call “taphonomic bias.” Using a simple model, which assumes a constant rate of site loss over time, we show how taphonomic bias can produce positive curvilinear frequency distributions through time even in cases of population stasis, decline, and fluctuation. We conclude that caution must be used when attempting to infer demographic trends from frequency distributions alone.     

Croatian Appoxiomenos alloy composition and lead provenance study

An ancient bronze statue of an athlete with a strigil (known as Apoxiomenos) – was raised from the north Adriatic Sea in 1999. In order to help to determine its place and date of manufacture various scientific techniques were used. ¹⁴C dating performed by the Accelerator Mass Spectrometry (AMS) on the organic material found inside the statue gave calibrated dates between 100 B.C. and 250 A.D. Non-destructive analysis performed by portable X-Ray Fluorescence (XRF) system and external beam Particle Induced X-Ray Emission (PIXE) spectroscopy could not provide representative results for metal alloy composition due to the electrochemical deterioration of the surface of bronze in seawater. This was observed by the analysis of alloy cross-sections performed by the proton microprobe. The analysis showed much higher lead concentrations on the surface of the bronze than inside, confirming that realistic alloy composition can be only performed on samples taken from at least 0.6 mm below the surface. Subsequent micro-PIXE analysis on metal cross-section showed inhomogeneous lead concentrations between 1 and 12%. Lead isotope analysis for provenance investigation has been done on 15 samples using Multi Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICP-MS). Analysis showed that lead isotope composition is consistent with some of the lead ores originating either from the Eastern Alps or from Sardinia. Altogether, the results lead to the conclusion that the statue is not of a Greek origin, but most probable it is a Roman copy of the Greek original.     

Dating Danish textiles and skins from bog finds by means of C AMS

This study presents the results of 44 new ¹⁴C analyses of Danish Early Iron Age textiles and skins. Of 52 Danish bog finds containing skin and textile items, 30 are associated with bog bodies. Until now, only 18 of these have been dated. In this paper we add dates to the remaining finds. The results demonstrate that the Danish custom of depositing clothed bodies in a bog is centred to the centuries immediately before and at the beginning of the Common Era. Most of these bodies are carefully placed in the bog – wrapped or dressed in various textile and/or skin garments. The care with which these people were placed in the bog indicates that they represent a hitherto unrecognised burial custom supplementing the more common burial pratice for this period.     

New age constraints for hominid footprints found on Jeju Island,South Korea

In 2004 numerous hominid footprints, along with diverse animal footprints, were found in the Late Quaternary strata of Jeju Island, South Korea. However, the age of the sediments in which the footprints were found is still controversial. Previous age estimates included radiocarbon ages of ca. 15,000 yr BP (Late Pleistocene) and quartz optically stimulated luminescence ages of ca. 7000 yr BP (mid-Holocene). In this study we report on 11 AMS ¹⁴C dating results from a new set of samples collected from the footprint-bearing strata and from associated sediments. Despite some variations and age reversal, all samples collected from the footprint-bearing strata yielded ¹⁴C ages of late Pleistocene. These ages are comparable with previous radiocarbon dating results. Furthermore, the presence of the proboscidean footprints attributable to woolly mammoths in the footprint-bearing strata supports the radiocarbon dating results. Based on the new radiocarbon dates and the presence of the alleged mammoth footprints, the age of the hominid footprints found at Jeju Island is thought to be late Pleistocene (about 19,000–25,000 cal yr BP). Therefore, this is the second discovery of hominid footprints dated to the Pleistocene age in Asia, and the first to be discovered in Korea.