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1.
Many archaeological sites were excavated in China, but rarely in the adjacent coastal areas. An archaeological site at Huangniliang in the coastal area of Shandong Province, northern China was excavated in 2013. Abundant stone artifacts including hammers, cores, flakes, chunks, and retouched tools are found in the silty aeolian sediments. In this study, optically stimulated luminescence (OSL) technique was employed to establish the chronological framework of the site. Medium-grained (45–63 μm) quartz was extracted from six sediment samples for dating. The equivalent doses obtained with the single-aliquot regenerative-dose (SAR) protocol are shown to increase with depth. Three samples from the stone-tool containing layer yield OSL ages ranging from 54 ka to 59 ka, providing the earliest geochronological evidence for the presence of humans in the eastern coast of Shandong peninsula during the early period of Marine Isotope Stage (MIS) 3.  相似文献   

2.
Discovered accidently during factory building construction works, the Middle Palaeolithic site of Biache-Saint-Vaast (Pas-de-Calais, France) was excavated from 1976 to 1982 by a team of Lille University directed by Alain Tuffreau. An abundant archaeological and paleontological material, including two human skulls, was there recovered from fossil alluvial deposits of the Scarpe River. In order to determine the ages of these remains, the ESR/U-series method was applied on bone and teeth. As the U-series data obtained of the main part of the analyzed tissues do not allow the use of the classical US-ESR model, the recently proposed AU-ESR model, taking into account if necessary U-leaching from some of the tissues, was used to calculate combined ESR/U-series ages for these samples. The obtained ages suggest a MIS7 attribution to the faunal remains and permit an age of ca 240 ka to be assigned for the human remains and associated archaeological material, in accordance with the stratigraphic data and the large mammal associations.  相似文献   

3.
The Visogliano shelter, in north-eastern Italy, is an important Middle Pleistocene occupation site where human remains were found together with an archaic lithic industry, including choppers, chopping tools and a few protobifaces. It is of utmost importance to try to document this period, when a second wave of settlement colonised Western Europe, carrying new flaking techniques and tools.Combined ESR/U-series analyses, integrated with biostratigraphical and environmental data, define a chronological frame for the layers from which the artefacts were unearthed. The lower levels, including human remains, can be dated to the 350–500 kyr time span, in agreement with micromammal and stratigraphical studies.These data make Visogliano one of the oldest palaeoanthropological sites in Italy, where human remains are directly associated with protobifaces, choppers and chopping tools. In Western Europe, Visogliano is contemporaneous to the G soil of the Arago Cave, France, with which it shares several similarities in faunal assemblages and radiometric data, and which contains human remains also. These data make Visogliano as one of the oldest sites in Europe where the Acheulian culture is observed.  相似文献   

4.
The Middle Pleistocene archaeological site of Guado San Nicola was discovered in 2005 in a fossil fluvial terrace of the Volturno River, close to the village of Monteroduni, Molise, Italy. Palaeontological remains and lithic artefacts, including both handaxes and Levallois, discoid and opportunistic debitage, were recovered in fluvial and slope sediments rich in volcanoclastic materials. This site includes four distinct human occupation levels. In two of them both “shaping-façonnage” and “knapping-débitage” technologies are highlighted, placing this site at the Lower/Middle Palaeolithic transition.In the present study, geochronological analyses by 40Ar/39Ar on single-crystal and ESR/U-series on teeth were performed to precise the chronological framework of the occupations. The 40Ar/39Ar data obtained securely bracket the human occupation levels at the transition between the interglacial and glacial marine isotopic stages MIS 11 (i.e. 400 ± 9 ka) and MIS 10 (i.e. 345 ± 9ka). The weighted mean age obtained from ESR/U-series dating of six teeth (i.e. 364 ± 36 ka) is in very good agreement with the 40Ar/39Ar results. The radio-isotopic constraints we presented place the Guado San Nicola site as one of the earliest testimonies of Levallois debitage in Western Europe and confirm the potential and accuracy of paleo-dosimetric methods to date Middle Pleistocene sites.  相似文献   

5.
It draws much attention of scientists how early hu- mans occupy and adapt to the rigorous climate and environment at high northern latitudes in East Asia after they stepped out of Africa, passed West Asia and finally arrived in East Asia[1-4]. Reliable age determi- nations of Paleolithic sites from northeastern Asia not only help to find out the earliest occupation of early humans in this region, but also relate to the founda- tion of the overall framework of human origin and migration[1-8]…  相似文献   

6.
This study presents palaeodosimetric results from the Middle Pleistocene archaeological site of Coudoulous I (Lot, SW France). Nine sedimentary quartz samples (41–60 μm) have been analyzed using a multiple aliquot protocol based on the measurement of the TT-OSL signal. In addition, 7 teeth and 7 bones have been dated by combining the ESR method with U-series analyses. Both methods gave consistent age results allowing correlation of the Early Middle Paleolithic Human occupation of the site to MIS 6 and part of the Lower Paleolithic tools to MIS 7. Beyond the establishment of a radiometric chronology for the Coudoulous I sequence, this study focuses on the information extracted from the intercomparison of the methods. Our data suggest that 1) the TT-OSL signal is stable over at least the last 230 ka (considering the age range of the studied samples), 2) there are not significant problems of incomplete bleaching leading support to the applicability of the TT-OSL technique for sedimentary deposits associated with karstic contexts. This approach highlights the interest of combining luminescence and ESR/U-series methods to discuss the reliability of the dating results.  相似文献   

7.
The efficient operation of a multipurpose reservoir requires information on high and low flows. However, analyses of inflows for high flows and for low flows are typically done independently. In this paper, we considered the joint dependence of the low flow on the preceding high flow volume and duration for the wet season in the Three Gorges region of the Yangtze River Basin in China. High flow volume and duration were found to have a strong association with the annual minimum 7-day flow in Cuntan, Wanxian, and Yichang stations. Furthermore, we identified the Arctic Oscillation, Pacific Decadal Oscillation, and snow cover in the Tibetan Plateau to have statistically significant teleconnections with the annual minimum 7-day flow. Bayesian models that consider a different level of pooling of the site by site regressions were then developed for the annual minimum 7-day flow conditional on the climate indices and high flow volume (or duration). The full pooling model performed best, suggesting that a homogeneous regional response is best identified given the global climate predictors. Statistics such as the deviance information criterion and reduction of error, coefficient of efficiency, and coverage rate under cross validation indicate the good performance of the model. Snow cover in the western Tibetan Plateau and high flow volume were identified as the most influential factors of the annual minimum 7-day flow through their impact on water storage in the basin. Recent simulations since June 2003, when the Three Gorges Dam operation started, were used to analyse the effect of dam operation on the annual minimum 7-day flow. A comparison of observations and predictions during the post-dam period demonstrated that the dam operation effectively modifies the annual minimum 7-day flow period to have higher flows.  相似文献   

8.
In connection with the future Seine-North Europe Canal (Seine-Scheldt), a large-scale rescue archaeological survey was conducted at Havrincourt (northern France) between 2008 and 2011. The discovery of several levels of Palaeolithic flint artefacts embedded in a relatively thick loess sequence (ca 6–7 m) preserved on a gentle slope facing North-East, resulted in a 6000 m2 excavation. This opened the opportunity for a detailed pedosedimentary and interdisciplinary geochronological survey (14C, optically stimulated luminescence, thermoluminescence, ESR/U-series) that has allowed us date the sequence reliably. On the basis of these results we propose this sequence as a new pedostratigraphic and archaeological reference sequence for northern France. We present here the optical dating of the sequence performed on fine (4–11 μm) quartz grains extracted from 17 samples. The luminescence characteristics of these extracts indicate that the single-aliquot regenerative dose optically stimulated luminescence (SAR-OSL) procedure that was applied is well suited. A consistent set of optical ages was obtained for the loess deposited up to around 70 ka ago. Independent age control (pedostratigraphy, 14C, ESR/U-series dates) allowed us to apply a Bayesian approach to build a chronometric model. This in turn enabled a regional chronostratigraphic framework to be built, to constrain the correlations with neighboring regions (northern France and Belgium) and to calculate a precise age for the four Palaeolithic levels discovered, including a unique occupation related to the early Upper Palaeolithic which was previously unknown in the area.  相似文献   

9.
The archaeological site of Payre (France) yielded Middle Palaeolithic layers with Neanderthal remains, which are partly bracketed by two stalagmitic flowstones. To obtain a precise chronological framework for the human occupation and the faunal remains of this site, several dating methods were used: uranium-series (U-series by alpha spectrometry and TIMS) and electron spin resonance (ESR) on stalagmitic flowstones, combined ESR/U-series on teeth and bones, and thermoluminescence (TL) on burnt flints. Most of the ages obtained for levels H to C range from 300 to 140 ka. The age-spread obtained for the anthropic (burnt flints) and faunal remains (bones and teeth) suggests that the dated levels represent several human occupation periods, near the transition from MIS8 to MIS7 (levels G–F) and from MIS6 to MIS5 (levels D–E).  相似文献   

10.
Xinglong Cave, containing four human teeth, numerous mammalian fossils, stone artifacts and a Stegodon tusk with intentional and seemingly grouped engravings, is one of the most significant archaic Homo sapiens sites in south China, located 95 km south of Fengjie County, in Chongqing. In an attempt to constrain the age of the human relics, calcitic flowstone deposits with a significant detrital component were dated by U–Th methods using a leachate scheme. Total sample digestion MC-ICPMS dating was used to assess the reliability of the leachate technique. Six calcite samples from horizons beneath and above the fossil-bearing layer were dated. We obtained ages of 130 ± 9.1, 124 ± 11, 135 ± 12 and 127 ± 11 ka for the flowstones above the fossil layer with a weighted mean of 128.9 ± 5.2 ka. Two flowstone samples gave MC-ICPMS dates between 128.3 ± 3.3 and 152.4 ± 25.3 ka with an assumed detrital component to correct for the initial 230Th, which are consistent with results obtained using the L/L regression data from layer U-4 within uncertainty. All errors herein quoted at the 2σ level. Ages determined for the flowstone underlying the fossil-bearing layer were 221 ± 29 to 189 ± 19 ka with a weighted mean age of 199 ± 16 ka. These results are stratigraphically consistent within error limits and show that the cave was occupied by Fengjie Man within the time range of ∼200 to ∼130 ka. These new U-series ages of flowstones in association with human teeth and an engraved stegodon tusk at the Xinglong Cave site provide valuable geochronologic information for the study of the origin of modern humans in East Asia and earliest human art.  相似文献   

11.
Zigui Basin is a major landslide-prone region in the Three Gorges Reservoir region of China, and the stabilizing pile is an effective and widely employed countermeasure to reinforce landslides in...  相似文献   

12.
利用乳山流动地震台网记录的2013年10月1日乳山M_L 3.8震群资料,基于Atkinson方法,计算得到该区Q值与频率f的关系:Q(f)=57.8 f ~(0.8562)。Moya方法仅依赖震源模型,计算绝对场地响应值,较能反映实际放大效应。采用该方法,计算14个流动地震台站场地响应,结果显示,场地响应在低频(1—2 Hz)放大作用不明显,而高频部分平均放大2—10倍,卓越频率3—10 Hz,且高频处场地响应衰减不明显。  相似文献   

13.
After the Salawusu and Shuidonggou sites, the Wulanmulun site found in 2011 is another important Paleolithic site in Ordos, China, due to its numerous stone artifacts and animal fossils. Here, we carry out a combined luminescence and radiocarbon dating of the site. The luminescence dating was done on coarse-grained quartz from 24 sediment samples using a single-aliquot regenerative-dose (SAR) protocol. The radiocarbon dating was performed on ten charcoal samples and one bone sample using acid-base-acid (ABA) and acid–base-wet oxidation-stepped combustion (ABOx-SC) pretreatments. The results showed that: (i) although some samples show relative large (>20%) overdispersion in De distribution (small aliquots), the quartz grains are considered to be sufficiently bleached before burial; (ii) the quartz OSL ages of ∼4–65 ka obtained for the samples are generally stratigraphically consistent and reliable; (iii) the radiocarbon ages obtained using the ABA pretreatment procedure are much younger than the corresponding OSL ages, and the radiocarbon ages obtained using the ABOx-SC method are beyond or close to the laboratory background. The radiocarbon ages obtained using the ABA treatment were considered to be underestimated. This implication is that caution must be taken for dating Chinese Paleolithic (>25 ka) using the ABA pretreatment procedure on carbon samples. Finally, the cultural layers from the Wulanmulun site are deduced to be between 50 and 65 ka.  相似文献   

14.

考古磁学技术为考古遗址的受热历史研究提供了重要的定性/定量分析方法.黑龙江省东北部的小南山是中国东北地区重要的史前遗址之一,该遗址记录的最早人类活动可以追溯到更新世末期.遗址揭露了距今约16 ka以来序列性的人类生活遗物及遗迹,包括大量的石制品和少量的陶片,以及与当时人类生活方式相关的疑似用火遗迹.本文对小南山遗址内疑似用火区及周边的散土样品进行了一系列岩石磁学测试,包括低频磁化率、逐步磁化率随温度变化曲线(χ-T)、磁滞回线、等温剩磁获得曲线、反向场退磁曲线和一阶反转曲线(FORC)等,旨在通过磁学指标为遗址受热温度、受热范围等信息提供定量化证据.实验结果显示,采样区域内两处疑似用火区(ZB、ZC)磁化率普遍偏高、逐步χ-T曲线在400~600℃之间表现出较好的热稳定性、饱和等温剩磁偏强、FORC信号偏强;而表层烧土被清理后的疑似用火区(ZA)和非疑似用火区磁化率普遍偏低、逐步χ-T曲线显示样品在加热过程中逐渐发生热变化、饱和等温剩磁和FORC信号偏弱.这些磁学特征意味着ZB、ZC两处疑似用火区曾受过加热烘烤,而从ZA采集到的样品和疑似用火区外的样品则可能没有受热.逐步χ-T曲线结果显示疑似用火区高磁化率样品在400~600℃之间表现出较好的热稳定性,而当温度达到700℃时则发生明显的热转化,指示样品历史最高受热温度应该在600~700℃之间.

  相似文献   

15.
H. Moradkhani 《水文研究》2014,28(26):6292-6308
In this study the impact of climate change on runoff extremes is investigated over the Pacific Northwest (PNW). This paper aims to address the question of how the runoff extremes change in the future compared to the historical time period, investigate the different behaviors of the regional climate models (RCMs) regarding the runoff extremes and assess the seasonal variations of runoff extremes. Hydrologic modeling is performed by the variable infiltration capacity (VIC) model at a 1/8° resolution and the model is driven by climate scenarios provided by the North American Regional Climate Change Assessment Program (NARCCAP) including nine regional climate model (RCM) simulations. Analysis is performed for both the historical (1971–2000) and future (2041–2070) time periods. Downscaling of the climate variables including precipitation, maximum and minimum temperature and wind speed is done using the quantile‐mapping (QM) approach. A spatial hierarchical Bayesian model is then developed to analyse the annual maximum runoff in different seasons for both historical and future time periods. The estimated spatial changes in extreme runoffs over the future period vary depending on the RCM driving the hydrologic model. The hierarchical Bayesian model characterizes the spatial variations in the marginal distributions of the General Extreme Value (GEV) parameters and the corresponding 100‐year return level runoffs. Results show an increase in the 100‐year return level runoffs for most regions in particular over the high elevation areas during winter. The Canadian portions of the study region reflect higher increases during spring. However, reduction of extreme events in several regions is projected during summer. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

16.
ESR dating has been widely used in seismic assessment. In this paper, we collected fault gouge samples systematically for ESR (Electron Spin Resonance) dating, and sediment samples of overlying strata, and offset strata for OSL (Optically Stimulated Luminescence) dating along Xiaoshan-Qiuchuan fault (XQF) trending NE-SW, Xiaofeng-Sanmen fault (XSF) trending NW-SE, and Changhua-Putuo fault (CPF) trending E-W. In the same fault outcrop, the ESR data of fault gouge is greater than the OSL data of the strata of...  相似文献   

17.
在杭州地区,根据系统采集的萧山——球川断裂、孝丰——三门湾断裂和昌化——普陀断裂的断层泥ESR年龄,以及地层的光释光年龄的统计分析表明,对同一断层同一段而言,断层泥ESR年龄大于地层光释光所给出的断层最后一次活动时代,并不能反映杭州地区各个断裂最后一次活动时代,而是反映了断裂历次较强活动的历史. 在距今100——58万年,各断裂均有活动;58——45万年断裂活动性减弱;45——20万年仅萧山——球川断裂活动;10万年以来杭州地区整体处于弱地震背景. 以孝丰——三门湾断裂为界,萧山——球川断裂第四纪的活动具有鲜明的分段性.   相似文献   

18.
19.
The Three Gorges Reservoir(TGR)in China is the largest hydroelectric project in the world,but the threat of sediment affecting ecological sustainability of the reservoir is a topic of concern.Sediment particlesize distribution(PSD)is informative in understanding sediment transport dynamics and biochemical functions.It is,therefore,important to quantitatively characterize the distribution of sediment particles.In the current study,fractal theory is applied to determine the PSD of suspended sediment in the TGR.The results show that the volumetric fractal dimension(D_v)exhibits a significant seasonal difference(p<0.05),reflecting sediment source and hydrodynamic sorting control the granularity of suspended sediment in the TGR.More specifically,suspended sediment particles are coarser in the wet season than in the dry season for the Yangtze River,and the opposite is true for the Ruxi River,an important tributary.The generalized dimension spectrum,D(q)-q,and multifractal singularity spectrum,f[α(q)]-α(q),were calculated for each suspended sediment sample.Thereafter,the parameters,D(0),D(1),D(2),α(0),Δα(q),andΔf[α(q)],were determined to characterize the PSD.As a result,the coarser suspended sediment during the wet season is characterised by a more complex PSD pattern,with a wider range of particle sizes,greater heterogeneity,and greater homogeneity of distribution over the measurement interval.However,the multifractal structure of the PSD of suspended sediment is more complex during the dry season than during the wet season,with higher local dispersion and variability.The findings of the current study highlight that multifractal analysis provides important insight for understanding the PSD of suspended sediment in the TGR.  相似文献   

20.
长江三峡地区地球物理异常带的地表地质特征   总被引:2,自引:0,他引:2  
陈永成 《华南地震》2000,20(1):61-65
通过对长江三峡地区(巴东-宜昌段)野外地质调查获得的实际资料研究,认为沿长江北西西向地球物理异常带在地不存在着相应的断层破碎带及裂隙密集带。地下深处与地球物理异常带相对应的基底断裂已切穿中、新生代沉积盖层,在地不形成一组北西西向断裂带,现代地震活动与这组断裂带有密切的关系。  相似文献   

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