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1.
广西百色盆地旧石器工业因含有众多的手斧且年代早到803 kaBP而闻名于世。盆地内发育有7级河流阶地,其中第IV级阶地发现有手斧和玻璃陨石。自从1973年第一个石器地点被发现,越来越多的遗址或地点被调查发现和发掘。以前研究认为,百色盆地旧石器只出自网纹红土层,年代均为803 kaBP。2013年以前,通常只在土状堆积的上部发掘,从来没有人对第IV级阶地的沉积物从地表到底部砾石层进行系统发掘,因此关于第IV级阶地的整体地层堆积情况及含石器层位很模糊。2013-2014年,广西文物保护与考古研究所会同田东县博物馆对百色盆地最重要的旧石器遗址之一——田东高岭坡遗址进行了系统的考古发掘。此次发掘从遗址的地表往下一直发掘到砾石层,揭露出厚度超过7m的完整地层序列,发现1处小型石器制造场和1处用火遗迹。在不同地层中发现石制品800多件,包括砍砸器、手镐、刮削器等。涵盖旧石器和新石器两个时代。根据地层对比和石制品的特征及测年结果,我们把旧石器时代文化遗存可分为3期:第一期的年代早于或等于803 kaBP,第二期为15 kaBP,第三期约为10 kaBP。  相似文献   
2.
《L'Anthropologie》2016,120(5):588-609
The study of graphic convergences and divergences in Palaeolithic art is used to understand the culture, territories and interaction systems of human groups. La Covaciella cave has fifteen animal representations and other linear, dots and geometric motifs. The bison stands out; some were executed with complex technical procedures. Two of them were dated by C14 AMS, obtaining a result of 14,260 ± 130 BP (17,733–16,973 cal BP) and 14,060 ± 140 BP (17,503–16,260 cal BP). These correspond chronologically with the beginning of the middle Magdalenian or the very end of the lower Magdalenian. Similar depictions to the bison at La Covaciella are located in other areas of Western Europe. The repertoire of parietal bison displaying graphic similarities with those at La Covaciella is very large; both of the Pyrenean model (Niaux morphotype) and of the Perigordian model (Font-de-Gaume morphotype). A first consideration derived from the search for comparisons involves a new interpretation of the territorial value implied by the term Pyrenean style (Asturias, Cantabria, Basque Country, Navarre, Pyrénées-Atlantiques, Hautes-Pyrénées, Haute-Garonne, Ariège, Dordogne, Lot, Ardèche and Vienne). The Font-de-Gaume parietal morphotype is most common in Dordogne. In addition, in some cases, spatial complementariness has been found, with both graphic morphotypes. This article proposes different chronological and anthropological hypothesis to explain the distribution and coexistence of the two graphic models.  相似文献   
3.
Spillway scour lakes and basins in northwestern Saskatchewan were cored to determine when the spillways were abandoned. The cores contained the target contact of organic muck (gyttja) overlying inorganic sand or silty-clay rhythmites. New AMS radiocarbon dates on terrestrial macrofossils, in conjunction with previously published and unpublished data from the area, indicate that the spillways were abandoned between 9.07 and 9.59 14C kyr BP (10,220-10,810 cal yr BP). Of great interest is whether the channels are associated with northwestern drainage from glacial Lake Agassiz. The radiocarbon ages recording spillway abandonment are consistent with previous work, which claims that overflow through the northwestern outlet ended ∼ 9.5 14C kyr BP (10,700 cal yr BP); this is consistent with shifting drainage to the southern outlet at this time. The scarcity of dates from the northwestern outlets and other outlets of Lake Agassiz underscores the need to establish a tighter chronological control on outlet switching before outburst flooding from Lake Agassiz can be assumed to be the trigger for abrupt climate change.  相似文献   
4.
《L'Anthropologie》2022,126(1):102973
The lithic industries of the sites Kermek, Ciscaucasia (2.1–2.0 Ma) and Karakhach, South Caucasus (1.85–1.78 Ma) contain almost all the components of the Acheulian, indicating that this techno-complex appeared in the different areas of the Caucasus region not later than at the end of the Gelasian. Such extremely old ages of these industries as well as a number of their features due to the influence of the local raw material (tabular clasts) suggest that they were formed independently of the Early Acheulian industries known in Africa and the Near East. The very early appearance and further dispersal of Early Acheulian in the Caucasus can be explained by the presence there of raw materials with qualities supporting the production of large tools inherent of Acheulian, and by the very favorable natural conditions of the region in the final Gelazian-initial Calabrian (low or medium altitude terrain with subtropical climate and savanna-like landscape).  相似文献   
5.
The archaeological deposits at Mumba rockshelter, northern Tanzania, have been excavated for more than 70 years, starting with Margit and Ludwig Köhl-Larsen in the 1930s. The assemblages of Middle Stone Age (MSA) and Later Stone Age (LSA) artefacts collected from this site constitute the type sequences for these cultural phases in East Africa. Despite its archaeological importance, however, the chronology of the site is poorly constrained, despite the application since the 1980s of several dating methods (radiocarbon, uranium-series and amino acid racemisation) to a variety of materials recovered from the deposits. Here, we review these previous chronologies for Mumba and report new ages obtained from optically stimulated luminescence (OSL) and infrared stimulated luminescence (IRSL) measurements on single grains of quartz and multi-grain aliquots of potassium (K) feldspar from the MSA and LSA deposits. Measurements of single grains of quartz allowed the rejection of unrepresentative grains and the application of appropriate statistical models to obtain the most reliable age estimates, while measurements of K-feldspars allowed the chronology to be extended to older deposits. The seven quartz ages and four K-feldspar ages provide improved temporal constraints on the archaeological sequence at Mumba. The deposits associated with the latest Kisele Industry (Bed VI-A) and the earliest Mumba Industry (Bed V) are dated to 63.4 ± 5.7 and 56.9 ± 4.8 ka (thousands of years ago), respectively, thus constraining the time of transition between these two archaeological phases to ∼60 ka. An age of 49.1 ± 4.3 ka has been obtained for the latest deposits associated with the Mumba Industry, which show no evidence for post-depositional mixing and contain ostrich eggshell (OES) beads and abundant microlithics. The Nasera Industry deposits (Bed III) contain large quantities of OES beads and date to 36.8 ± 3.4 ka. We compare the luminescence ages with the previous chronologies for Mumba, and briefly discuss how the revised chronology fits in the context of existing archaeological records and palaeoclimatic reconstructions for East Africa.  相似文献   
6.
Temperate wetlands in the Northern Hemisphere have high long-term carbon sequestration rates, and play critical roles in mitigating regional and global atmospheric CO2 increases at the century timescale. We measured soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) from 11 typical freshwater wetlands (Heilongjiang Province) and one saline wetland (Jilin Province) in Northeast China, and estimated carbon sequestration rates using 210Pb and 137Cs dating technology. Effects of climate, net primary productivity, and nutrient availability on carbon sequestration rates (Rcarbon) were also evaluated. Chronological results showed that surface soil within the 0–40 cm depth formed during the past 70–205 years. Soil accretion rates ranged from 2.20 to 5.83 mm yr−1, with an average of 3.84 ± 1.25 mm yr−1 (mean ± SD). Rcarbon ranged from 61.60 to 318.5 gC m−2 yr−1 and was significantly different among wetland types. Average Rcarbon was 202.7 gC m−2 yr−1 in the freshwater wetlands and 61.6 gC m−2 yr−1 in the saline marsh. About 1.04 × 108 tons of carbon was estimated to be captured by temperate wetland soils annually in Heilongjiang Province (in the scope of 45.381–51.085°N, 125.132–132.324°E). Correlation analysis showed little impact of net primary productivity (NPP) and soil nutrient contents on Rcarbon, whereas climate, specifically the combined dynamics of temperature and precipitation, was the predominant factor affecting Rcarbon. The negative relationship observed between Rcarbon and annual mean temperature (T) indicates that warming in Northeast China could reduce Rcarbon. Significant positive relationships were observed between annual precipitation (P), the hydrothermal coefficient (defined as P/AT, where AT was accumulative temperature ≥10 °C), and Rcarbon, indicating that a cold, humid climate would enhance Rcarbon. Current climate change in Northeast China, characterized by warming and drought, may form positive feedbacks with Rcarbon in temperate wetlands and accelerate carbon loss from wetland soils.  相似文献   
7.
黑龙江省的旧石器考古发掘与研究始于上世纪30年代,迄今为止已有正式报道或发表的遗址和地点100余处,分布在黑龙江省境内各处,年代上均属于旧石器时代晚期.2017年初,根据齐齐哈尔市查哈阳农场群众提供的线索,笔者等在甘南县环太平湖水库周边发现多处旧石器地点以及原料产地.经对该地区的踏勘调查和对一处地点的小规模剖面清理发现...  相似文献   
8.
《L'Anthropologie》2018,122(1):1-13
The Bose Paleolithic industry in the Bose Basin, Guangxi, South China is well known in the international scientific community for its bearing handaxes dated back to 803 ka. Seven terraces were developed in the basin and terrace 4 is the most important because handaxes and tektites were recovered from this terrace. Since the first site was discovered in 1973, additional sites of the Bose Paleolithic industry have been investigated and excavated, most of which are located on terrace 4. The previous studies concluded that there is only one phase within this industry and its age is 803 ka. However, before 2013, no attempt had been made to dig down to the basal gravels from the top of terrace 4 in archaeological excavations. Therefore, the stratigraphy and the layers from which the stone artifacts derive of terrace 4 are not clear. In 2013–2014, we conducted an excavation of 200 m2 at the Gaolingpo site, which is one of the most important Paleolithic sites in the Bose Basin. We excavated to the basal gravel deposits from the top of this terrace, and a section of more than 7 meters thick deposit was exposed and clearly shows the stratigraphic layers of Pleistocene and Holocene deposits. Furthermore, features and about 800 stone artifacts including choppers, picks, scrapers, etc. were excavated from several stratigraphic layers, which are different in age and other aspects. Based on stratigraphy and the stone artifacts, three stages of Paleolithic cultural remains from the Gaolingpo site can be established. The first stage is in the age of at leat 803 ka. The second stage can be dated to 15 ka and the third stage to about 10 ka.  相似文献   
9.
牛体外受精的程序及超微结构研究   总被引:12,自引:0,他引:12  
孙青原  秦鹏春 《动物学报》1996,42(3):303-308
牛体外成熟卵母细胞体外受精后3小时精子入卵,8小时原核形成,24小时的核多到卵中央。精子发生顶体反应的部位主要在透明表面,方式是顶体外膜自身囊经,发生顶体反应的粗子可斜向或垂直穿过透明带。卵丘细胞可吞噬大量精子,在阻多精受精中发挥重要作用。高尔基得合体,线料体、环状片层和滑面内质网等在原核周围形成细胞器集团。牛体外受精卵的雌雄原结合比体内受精的要延迟,胞吐到卵周隙中的皮质颗粒内容物扩散不完全。  相似文献   
10.
The Weichselian Late-glacial marks the transition from the Weichselian Late Pleniglacial to the warmer Holocene. During this period climate changed rapidly, as did vegetation and the abiotic landscape. For analysis of the relationship between these changes, accurate chronologies are essential. In the Netherlands, a compilation has been made of over 250 palynologically investigated sites relating to this period. A regional zonation has been constructed based on common trends in vegetation development. On palynological grounds, not only the classical Late-glacial sub-division but also minor changes can be recognized within the Allerod, Late Dryas and Early Preboreal. After a critical evaluation of the available radiocarbon dates this zonation has been attached to the14C timescale. Palynological changes which can be attributed to episodes of climatic cooling are recorded at 12 100, 11 500, 10 950 and 9950 B.P. The chronological framework made it possible to compare vegetation development with other proxy records. Climatic events recorded in oxygen-isotope records from Swiss lake sediments and the Greenland ice cores are also reflected in the regional vegetation development in the Netherlands. The regional trends in vegetation development expressed by the pollen zones are considered to be related to changes in climate, while anomalies reflect other, local environmental changes.  相似文献   
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