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61.
Two significant events in the late Holocene history of Madagascar were (a) the arrival of people, and (b) the loss of nearly two dozen species of land vertebrates in the socalled “subfossil extinctions”. The consensus is that the faunal losses occurred shortly subsequent to human arrival, but the timing of these events is poorly constrained. The minimum age for initial human presence on the island may now be set at approximately 2000 bp, on the basis of AMS 14C dates for human-modified femora of extinct dwarf hippos from SW Madagascar. Assuming that this date also marks the beginning of deleterious human interactions with the subfossil fauna, and assuming that this fauna became completely extinct by 900 bp, the width of the anthropogenic “extinction window” may have been as long as c. 1000 a. This estimate, nearly twice the length of previous ones, is close to the unadjusted minimum for the duration of the terminal Pleistocene extinction event in the Americas. Whether or not this length of time comports with theoretical expectations of a “blitzkrieg” pattern of losses is uncertain, but greater refinement in dating the end of the subfossil extinctions is unlikely to produce radically shorter estimates of duration.  相似文献   
62.
夏商周断代工程采用系列样品进行14C年代测定,得出了夏商西周的年代框架,与考古遗址相对应,解决了三代考古学的分期.登封王城岗古城约为公元前2070年,即夏的起始年代.偃师商城始建于公元前1600年,郑州商城始建于公元前1580年,前者早于后者,偃师商城遂成为夏商分界的界标.就作为都城而言,郑州商城开始作为王都的时间比起偃师商城开始作为王都的时间要晚得更多.  相似文献   
63.
64.
Anthropomorphic wooden figures found in peat-bogs east of the Urals are described. Their archaeological context, chronology, and stylistics are analyzed. The Uralian specimens are compared with those from Western and Eastern Europe. The possible meaning of these representations is reconstructed on the basis of Ob Ugrian rituals and mythology.  相似文献   
65.
Dendrochronology has proved useful in suggesting the provenance of timbers in northern Europe, particularly for ship‐timbers, which may have originated from a distant source. Historical chronologies are usually derived from timbers of uncertain origin. In trying to provenance a new chronology, therefore, trends in the geographical distribution of statistical matches should be viewed, rather than individual strong matches. While it is usual to test a site‐chronology created from several individual timbers, in a situation such as the Mary Rose, where individual timbers may have been sourced from several regions, the matches of individual timbers may shed light on their origins. © 2010 The Author  相似文献   
66.
The Longwangchan Paleolithic site, situated on the Yellow River terraces in the Hukou area, Shaanxi province, China, was found in 2003–2004, and two areas (Localities 1 and 2) of the site were excavated in 2005–2008. Abundant stone artifacts including microliths, a grinding stone fragment and a shovel, with some animal bones and shells, were recovered from Locality 1. In this study, the cultural deposits from Locality 1 were dated using radiocarbon and optical dating techniques, and the sediment properties of the deposits were analyzed. The results show that the age of the deposits ranges from 29 to 21 ka and most of them were deposited between 25 ka and 29 ka. This indicates that corresponds to late Marine Isotope Stage (MIS) 3 and early MIS 2. During the human occupation period, the climate in this area became colder and drier. Sediments from beds where the grinding slab and the shovel were found were dated to ∼25 ka, which is the oldest among the grinding stones found in China. The microliths and the grinding stone are important evidence for an incipient socio-economic process that eventually led to the regional transition from hunting-foraging to farming.  相似文献   
67.
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。  相似文献   
68.
Abstract

Dating terraces, the most prominent feature of the agricultural landscape in many parts of the world, is a problem for archaeologists. This study presents an interdisciplinary approach that combines archaeological survey and excavations with direct sediment dating of terrace fill using Optically Stimulated Luminescence (OSL). The study focuses on Ramat Rahel, a multi-period site located in the southern outskirts of modern Jerusalem, Israel, where, on a defined terraced slope chosen for a small-scale landscape archaeology project, three main phases of terrace construction and use were identified. The earliest phase dates to the Late Byzantine/Early Islamic period, the second to medieval times, and the last to the Ottoman period. The results enable a comprehensive reconstruction of the changing local landscape through time and demonstrate the validity of OSL, when combined with archaeological investigations, as a reliable method for terrace dating.  相似文献   
69.
Examination of fibers from a colored fabric fragment from Seip Mound Group, Ohio, demonstrates the utility of sequencing analytical techniques: (1) minimally destructive pretreatment to remove humic acids followed by plasma-chemical oxidation, in preparation for accelerator mass spectrometric determination of radiocarbon age and (2) direct analysis in real time mass spectrometry (DART-MS) of the pretreatment solution, for the determination of red colorants. Pretreatment followed by plasma-chemical oxidation provided the opportunity to date 3?mg of fiber using just 200?mcg of carbon. Examination of the pretreatment solution by DART-MS confirmed the composition of anthraquinones consistent with those from bedstraw root (Galium sp.). The date determined (1,805?±?35 B.P.) places the textile in the midrange of radiocarbon dates previously obtained for the Seip earthworks; identification of the dye plant shows that the Hopewell possessed a sophisticated knowledge of plants and their uses.  相似文献   
70.
Only a few astrophysical points and synchronisms listed in texts provide anchor points for the absolute chronology of Ancient Egypt. At first we will show how we can re-calculate some of these anchor points by using Sothic dating based on the arcus visionis method, and modelling lunar dates using a Bayesian approach. Then, we will discuss two radiocarbon studies carried out on short-lived Egyptian materials held at the Louvre Museum that could be attributed to particular reigns or other precise periods. Using a Bayesian approach, these dates were combined with the known order of succession and the lengths of reigns. Sothic and lunar dates were integrated as priors in the model. This approach has led to a new proposal for the absolute chronology of Egypt's 18th Dynasty.  相似文献   
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