基于HSI彩色模型灰度分量的宁夏岩画断代研究初探

岩画是古代先民生产、生活、祭祀等活动的生动记载,是人类文明的史诗,岩画的断代一直是岩画研究的难点,文中提出了一种基于色度、饱和度和灰度(HSI)彩色模型的数字图像处理技术提取岩画灰度值(I)的方法,利用岩画灰度值与岩画作画年代之间的线性可比关系,测定岩画的年代。此方法能提取整个岩画中的灰度值,避免了手工提取有限个点的缺陷。试验结果表明此方法能为岩画的断代提供一种可参考的、简便的、快速的计算机解决方法,但测定年代的准确性依赖于选取的岩画标尺年代的准确性。     

ONLY TIME WILL TELL: A REVIEW OF THE METHODOLOGY OF DIRECT ROCK ART DATING

Epistemology has not kept pace with the progress experienced in the direct dating of rock art. This paper reviews the experimental methods that have been developed in recent years. While many do provide important information about the possible age of rock art, it is of concern that the precipitate archaeological interpretations these data are used for are often not warranted. Some are attributable to not understanding the severe qualifications that apply to most dating results, others perhaps to over-enthusiasm on the part of some researchers. The introduction of archaeological dynamics into direct dating of rock art threatens the reliability of this young methodology. Some of the pitfalls are considered in this paper, and a general rationale for the direct dating of rock art is developed.     

Rock surface luminescence dating of prehistoric rock art from central Iberia

Rock art paintings are notoriously difficult to date numerically. Recently, luminescence dating has been shown to provide reliable rock surface burial ages in various archaeological settings. Here we use the cross-cutting relationship between a fallen rock and two paintings of the Iberian Levantine (older) and Schematic (younger) styles to constrain the age of the paintings by dating the rockfall event using rock surface luminescence dating. Infrared-stimulated luminescence (IRSL) signals as a function of depth into the buried face of the talus border indicate that the IRSL signal measured at 50°C (IR₅₀) was sufficiently reset to a depth of about 1.6 mm prior to burial. An uncorrected IR₅₀ age of 1.6 ± 0.2 ka was calculated for the rockfall event by dividing the surface equivalent dose (D_e) by the total dose rate. This age was corrected using both conventional and field-to-laboratory saturation approaches to yield indistinguishable ages of 2.7 ± 0.5 and 2.9 ± 0.3 ka, respectively. Since the panel with Schematic art was first available to the artist after the rockfall, we conclude the Schematic rock art at Villar del Humo is younger than ~2.9 ka. The Levantine rock art was painted on a panel constrained by the talus boulder before detachment, and so it is likely to be older than ~2.9 ka.     

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).     

Lichenometric constraints on the age of the Huashan Grottoes, East China

Lichenometry is a method of dating that has been widely used in glaciated areas for determining the minimum age of exposure of a geomorphic landform during the late Holocene. This paper presents a regional calibration data set of lichen thallus sizes versus rock surface ages for the Huashan area, East China, based on measurements of yellow-green Rhizocarpon lichens on the known-age substrates at eight sites. An empirical relationship between thallus sizes and rock surface ages was established using both the traditional regression and the Bayesian approaches. Using the Bayesian calibration, the minimum age of the Huashan Grottoes was dated from 450 ± 60 to 330 ± 60 years ago, corresponding to the late Ming Dynasty (AD 1477–1632). These dates are generally consistent with those predicted from the regression-based linear growth curve. Our results suggest that applications of this technique can be safely extended to the non-glaciated areas.     

Uranium series dating reveals a long sequence of rock art at Altamira Cave (Santillana del Mar,Cantabria)

The rock art in Altamira Cave was the first ensemble of Palaeolithic parietal art to be identified scientifically (Sautuola, 1880). Due to the great thematic, technical and stylistic variety of the art in the cave, which constitutes one of the most complete Palaeolithic art ensembles, Altamira was listed as World Heritage by UNESCO in 1985. Uranium-series dating has recently been applied to figures on the decorated ceiling in the cave. Several motifs are partly covered by thin layers of calcite precipitates, whose formation process is datable by this method. The results provide the date when the calcite formed, which gives a minimum age for the underlying depictions. These results confirm that the parietal art at Altamira was produced during a prolonged period of time, at least 20,000 years (between 35,000 and 15,200 years ago), and that part of the ensemble corresponds to the Aurignacian period.     

How old are Australia's pictographs? A review of rock art dating

Australia contains some of the world's richest and apparently longest traditions of rock pictographs. Dating this art, however, has been problematic, with few ‘direct’ and reliable dates of Pleistocene or early Holocene age having been obtained from visible, representational imagery. This paper critically reviews the evidence for the antiquity of pigment rock art in Australia by examining the various dating techniques employed. The accurate and reliable dating of rock art worldwide is crucial to understanding the evolution of modern human symbolism and whether cognitive modernism came about after, rather than with, the first signs of full biological modernism; understanding the pitfalls and devising proper methods are crucial prerequisites. Towards these ends, this paper reviews the results and techniques that have been employed to date the apparently earliest known pictographs in Australia.     

岩画断代研究——科技考古学领域中一个亟待解决的问题

探索和研究表明,岩画断代问题仍然是困扰岩画研究的难题之一,其主要原因是岩画本身不能够提供可供断代的直接依据。本文综述了目前岩画断代研究中经常使用的自然科学和考古学方法及其存在的问题,提出应用AMS14C是今后研究我国岩绘画断代问题的首选方法,解决岩刻画的断代问题则主要有赖于微腐蚀方法。     

Investigating the resetting of OSL signals in rock surfaces

There are many examples of buried rock surfaces whose age is of interest to geologists and archaeologists. Luminescence dating is a potential method which can be applied to dating such surfaces; as part of a research project which aims to develop such an approach, the degree of resetting of OSL signals in grains and slices from five different cobbles/boulders collected from a modern beach is investigated. All the rock surfaces are presumed to have been exposed to daylight for a prolonged period of time (weeks to years). Feldspar was identified as the preferred dosimeter because quartz extracts were insensitive. Dose recovery tests using solar simulator and IR diodes on both K-feldspar grains and solid slices taken from the inner parts of the rocks are discussed. Preheat plateau results using surface grains and slices show that significant thermal transfer in naturally bleached samples can be avoided by keeping preheat temperatures low. Equivalent doses from surface K-feldspar grains were highly scattered and much larger than expected (0.02 Gy to >100 Gy), while solid surface slices gave more reproducible small doses (mean = 0.17±0.02 Gy, n = 32). Neither crushing nor partial bleaching were found to be responsible for the large scattered doses from grains, nor did the inevitable contribution from Na-feldspar to the signal from solid slices explain the improved reproducibility in the slices. By modelling the increase of luminescence signal with distance into the rock surface, attenuation factors were derived for two samples. These indicate that, for instance, bleaching at a depth of 2 mm into these samples occurs at about ∼28% of the rate at the surface. We conclude that it should be possible to derive meaningful burial doses of >1 Gy from such cobbles; younger samples would probably require a correction for incomplete bleaching.     

U-Pb dating of zircon: A sourcing method for pottery from La Morena archaeological site,north-west Colombia*

U-Pb zircon radiometric dating and petrographic thin-section analysis were used for provenance identification of Ferrería and Marrón Inciso pottery styles from La Morena archaeological site in northwestern Colombia. U-Pb dating was applied to zircons recovered from pottery and rock samples from nearby geological units. The results suggest at least three distinct sources: the metamorphic rock unit on which the archaeological site is located, a granodiorite unit that outcrops further away from the site, and a mafic rock that cannot be attributed with certainty. U-Pb in zircons proved to be effective as a provenance method, where ages of the possible source rocks are well constrained, and can be applied to areas where traditional sourcing methods may be problematic.     

Thermoluminescence age of quartz xenocrysts in basaltic lava from Oninomi monogenetic volcano, northern Kyushu, Japan

We determined the eruption age of basaltic rocks by application of thermoluminescence (TL) method, which is often used for TL dating, to quartz. Mafic magma only rarely includes quartz because of their mutual disequilibration. The basaltic lavas reported herein include quartz as xenocrysts, as corroborated by their rounded or anhedral shape. The basaltic lava used for this study is from the Oninomi monogenetic volcano in northern Kyushu, Japan. The volcano eruption was estimated as occurring 7.3–29 ka because the lava exists between two widespread tephras: Aira-Tanzawa ash (26–29 ka) and Kikai-Akahoya ash (7.3 ka). We succeed-ed in collecting ca. 200 mg of quartz by decomposition of 30 kg of the lava samples. TL measurements for the lava indicate the eruption age as 15.8 ± 2.5 ka, which is fairly consistent with the stratigraphical estimation. Although the TL method has played a considerable part in constraining the timescale of Quaternary events, its application has been limited to silicic samples. The present result demonstrates the availability of quartz for dating even of mafic rock.     

SIMS‐SS,A NEW OBSIDIAN HYDRATION DATING METHOD: ANALYSIS AND THEORETICAL PRINCIPLES*

The water diffusion mechanism in obsidian has been revisited with the advent of a new dating approach employing secondary ion mass spectrometry (SIMS). The water diffusion SIMS(+) profile and the concept of a surface saturation (SS) layer in obsidians both provide a sound basis for the new diffusion age equation (SIMS‐SS) and are supported by dated world examples ( Liritzis et al. 2004 ). Here, we present the basic physical–chemical analysis of the mass transport phenomenon on which the new dating method is based. The crucial age parameter of the SIMS‐SS dating approach for archaeological obsidians—that is, the surface saturation (SS) layer—is supported by both theoretical and experimental data.     

Comparison of fluoride and direct AMS radiocarbon dating of black bear bone from Lawson Cave,Missouri

Abstract

After a 20-year hiatus (1955–1975) during which few archaeologists discussed fluoride dating, the method again received attention in the 1980s and 1990s when some argued for its validity. As a dating method, fluoride dating depends on the rate at which fluorine ions replace hydroxyl ions in osseous tissue. The rate of replacement is influenced by the properties of the skeletal part (SP), sediment chemistry (K), and sediment hydrology (H), and the replacement rate influences estimates of time. Calibrated AMS radiocarbon assays of 10 black bear (Ursus americanus) femora from a natural-trap cave in central Missouri are weakly correlated with fluorine concentrations, determined by neutron activation analysis in the 10 femora. Despite minimal variation in SP, K, and H, results indicate fluoride dating can be considered a valid dating method only in cases when the chronological validity of its results are confirmed with independent chronometric data. As similarities in fluorine amounts across specimens increase, provenience information and bone orientation data as well as fine resolution data on K and H become critical to the application of fluoride dating.     

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.     

浙江仙居岩画的微腐蚀断代

微腐蚀测年通过观测矿物晶体上的"石亏"来获知岩画的制作年代,是一种无损的"直接断代法"。仙居岩画的测年工作主要在送龙山和小方岩两处地点开展,经过观测,研究人员从岩画刻槽中取得了十一组石亏微腐蚀数据,以及两组来自吴芾墓附属石刻的校准数据。由校准后的年代计算结果可知,小方岩岩画的制作开始于东吴末年,贯穿了两晋及南北朝时期,一直延续至唐初,而送龙山岩画则为唐代作品。     

A review of rock art dating in the Kimberley, Western Australia

This paper critically reviews the various approaches used to estimate the age of the rock art in the Kimberley region of Western Australia. They include: (i) the relative superimposition of styles; (ii) the use of diagnostic subject matter (depictions of extinct animals, stone tool technology, introduced European and Asian objects and animals); (iii) the recovery of a ‘painted’ slab from a dated archaeological unit; (iv) radiocarbon dating of beeswax figures, charcoal pigments, organic matter in overlying mineral deposits and ‘accreted paint layers’ (oxalate rich crusts and amorphous silica skin), pollen grains from an overlaying mud-wasp nest; and (v) optically stimulated luminescence (OSL) dating of quartz grains from overlying mud-wasp nests. Future directions for rock art dating in the Kimberley include uranium-series dating of overlying and underlying mineral deposits.     

OSL and TL dating of the Middle Stone Age sequence at Diepkloof Rock Shelter (South Africa): a clarification

Diepkloof Rock Shelter offers an exceptional opportunity to study the onset and evolution of both Still Bay (SB) and Howiesons Poort (HP) techno-complexes. However, previous age estimates based on luminescence dating of burnt quartzites (Tribolo et al., 2009) and of sediments (Jacobs et al., 2008) were not in agreement. Here, we present new luminescence ages for 17 rock samples (equivalent dose estimated with a SAR-ITL protocol instead of classical MAAD-TL) as well as for 5 sediment samples (equivalent dose estimated with SAR-single grain OSL protocol) and an update of the 22 previous age estimates for burnt lithics (modified calibration and beta dose estimates). While a good agreement between the rock and sediment ages is obtained, these estimates are still significantly older than those reported by Jacobs et al. (2008). After our own analyses of the sediment from Diepkloof, it is suspected that these authors did not correctly chose the parameters for the equivalent dose determination, leading to an underestimate of the equivalent doses, and thus of the ages.     

OSL dating as an alternative tool for age determination of relic charcoal kilns

Chronometric studies of charcoal production remains are largely based on ¹⁴C-dating of associated charcoal. Owing to intrinsic limitations, however, this method provides no meaningful time resolution for post-1650 CE features. We investigate the potential of optically stimulated luminescence (OSL) dating of heated sandy sediments as an alternative and complementary tool for dating charcoal kiln remains. Seven samples from five relic charcoal kilns and 11 complementary samples from the underlying sandy substrate are used. Through a range of procedural tests, we demonstrate that the single-aliquot, regenerative-dose procedure in combination with OSL signals from quartz allows determining equivalent doses both accurately and precisely. For four of the five investigated kilns, OSL ages are consistent with independent age information from ¹⁴C-dating and written sources. Especially for post-1650 CE features, the precision can be significantly better than that of ¹⁴C-dating, and we highlight the potential of OSL dating for distinguishing, relatively, between charcoal production phases with an unprecedented time resolution. We conclude that the approach is a promising alternative to ¹⁴C.     

青海民和县寺沟峡岩画调查简报

2019年,丝绸之路南亚廊道调查队在青海省民和县寺沟峡内发现了4幅6组个体102个岩画,并对岩画进行了详细的调查、测绘和数字化扫描。从整个岩面的制作技法来看,有直接磨刻法和敲凿法。岩画主要以抽象图案为主,有少量人像、持物人物、鸟等具象形象。其形象与新石器晚期至青铜时代彩陶图案纹饰相似度较高,与中原地区岩画有着密切关系,为研究官亭盆地早期文化提供了新的突破口。     

Geoarchaeological studies on Roman time harbour sediments in Cologne — comparison of different OSL dating techniques

Due to the construction of a new North-South subway in Cologne, Roman time harbour sediments were exposed and were sampled for luminescence dating. A very good independent age control was given by the precise knowledge of the chronology of Roman activity and by radiocarbon ages of charcoal samples. Hence, different methodological approaches within luminescence dating were applied for Holocene heterogeneously bleached fluvial samples and were compared to the known ages. For one sample, optically stimulated luminescence (OSL) dating was applied to coarse-grained quartz using a single aliquot regenerative-dose (SAR) protocol. After D_e-measurements, different statistical approaches were tested (i.e. arithmetic mean, median, minimum age model, finite mixture model, leading edge method and the Fuchs and Lang approach). It is demonstrated that the Fuchs and Lang approach along with the leading edge method yielded the best matching OSL ages with respect to the known ages.