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1.
山东莒南发现的石制品   总被引:2,自引:1,他引:1  
员晓枫  徐淑彬等 《人类学学报》1989,8(1):32-38,,T001,
本文报道的128件人工石制品分别采自山东莒南县的石莲子乡烟敦岭和扁山乡九顶莲花山两个地点。石制品常见类型有边刮器,端刮器和砍斫器等,另有少量的雕刻器和尖状器,内含典型细石器。就石制品的组合及工艺水平而言,其时代可能属于旧石器时代末期。  相似文献   
2.
IntheareatobefloodedinthesecondengineeringstagefortheDanjiangreservoir,wediscovered16vertebratefossillocalitiesand52Paleolithicsitesin1994,andcollected603artifactsandmanyfossils.Ofthel6new1yfoundvertebratefossillocalities,threearereptilesitesrepresentedbydinosaureggsandlimbbones,andl3producemamma1s,including4Pale0gene,2Ne0geneand7Quaternarysites'ThemammalianlocalitiesareofPale0cene,Eocene,EarlyMiocene,andPli0ceneorEarlyPleistocene,MiddleandIntePleistocene,respectively.Theyfillinsomestrat…  相似文献   
3.
泾河流域旧石器考古工作开展很早,1920年法国神父桑志华(E.Licent)在甘肃庆阳地区赵家岔、辛家沟黄土堆积中发现石英质石制品,标志着中国旧石器考古的开端。在之后的近100年时间里,学者们陆续在属于泾河流域的甘肃庆阳、平凉等地发现牛角沟、寺沟口、楼房子和陕西长武窑头沟、乾县大北沟等旧石器地点,这些发现丰富了泾河流域旧石器文化内涵。然而,上述发现多集中在泾河中上游,且开展时间较早,下游地区特别是关中平原几乎是一片空白。本次调查在泾河流域中下游新发现旧石器地点16处,集中分布在关中平原泾河及支流的黄土堆积上。在黄土堆积中获取石制品63件,类型包括石核、石片和刮削器等,属于北方地区石片石器工业。根据石制品埋藏层位及泾河流域地貌发育和地层对比,初步推测这些地点时代为晚更新世。  相似文献   
4.
Corrosion and biofouling phenomena of cast iron and brass were evaluated under natural conditions to determine the degradation process of archeological artifacts. Field exposure studies of experimental materials were conducted over 15 months at an offshore position in the sea of Campeche in the Gulf of Mexico. Corrosion was determined by gravimetric measurements. The community structure of the benthic assemblage inhabiting the surfaces of both materials was evaluated. A total of 53 species was identified. The community in both cases was composed of a small number of species. Encrusting, attached and erect life forms were dominant on iron. Attached life forms were dominant on brass. Biofouling produced a decrease in the weight loss measurements of cast iron samples. Biofouling provided a beneficial factor for in situ preservation of iron archeological artifacts in wreck sites.  相似文献   
5.
多层计算机断层扫描(Multi-slice computed tomography,MSCT)具有时间及空间分辨率高的特点已经被广泛应用于脊柱术后评价,然而,因为术中植入金属植入物,CT图像由于其成像原理的限制,其图像质量受到金属植入物的严重影响,金属伪影大多来源于量子噪声、散射线和射束硬化效应,降低图像的对比度,使细微解剖结构显示不清,从而使得感兴趣区域的检测能力降低,其图像质量明显下降,甚至使临床医师做出错误的诊断,因此,为了做出更准确的腰椎术后并发症诊断和术后评估,使金属伪影最小化成为关键。能谱CT及其扫描及重建技术可以有效的去除腰椎术后产生的金属伪影,改善图像质量,本文能谱CT在腰椎术后金属伪影去除方面的应用进行综述。  相似文献   
6.
《L'Anthropologie》2016,120(3):237-262
The Lower Palaeolithic site of Menez-Dregan I is currently the subject of an important excavation and has been part of a multidisciplinary project since 1991. It is an ancient marine cave whose roof has gradually collapsed and thus partly protected the site from erosion. In Menez-Dregan 1, the sedimentological evidence has been significantly reduced due to multiple episodes of marine erosion in the cave (low sedimentary preservation in terms of sedimentation and erosion process). However, the proximity of a section with a longer sedimentary record (Gwendrez cliff) has allowed for an attempt at correlation between the different deposits by way of a sedimentologic study applied to sandy marker beds (dunes). The resulting new data permitted a more precise chronostratigraphy of this site to be drawn up and contributed to further validation of dating. Three main stratigraphic units show distinct levels of human occupation at the site, separated by coastal deposits. The ESR dates tend to place the first human occupation in MIS 12 or at the end of MIS 13 (around 465,000 years). The ESR dating obtained at the base of layer 5 gave an age of 380,000 years. The geological analysis (sedimentology, stratigraphical correlations at short distance) tends to confirm these dates. The fauna has not preserved due to the acidic environment, leaving only the lithic industry to show how the human groups who settled at the site lived and, it is worth noting, mastered fire lighting, and or control, at a very early date (late MIS 13 or early MIS 12). The lithic industry from the upper levels (layer 5) is likely Colombanian and is composed of numerous flakes and cores alongside a great quantity of cobble tools (mostly choppers), fractured cobbles, and cobbles with isolated removals on various types of rocks, some cleavers and very rare bifaces. Additionally denticulates and notches form the main part of the light duty tools, together with scrapers. These retouched light duty tools are mainly made on flint, but quartz and glossy sandstone were also used. The last level of occupation (layer 4) probably shows the transition between Lower and Middle Palaeolithic. This may represent a regional cobble tool industry of the south armorican shoreline, however, it is still difficult to separate it totally from the classic European Acheulean from Northern France. These armorican lithic industries could indeed correspond with areas of specialised activities, as demonstrated for some Middle Palaeolithic groups with a cobble tools lithic industry. The notion of culture that could be chosen to explain this variability must be treated with caution, because it would only be based on the presence or absence of only one type of tool (the handaxe).  相似文献   
7.
2019-2020年,在黄河中游晋陕峡谷陕西一侧龙门至壶口段新发现9处旷野旧石器地点,采集石制品136件,部分石制品直接采自地层剖面上。康家岭地点石制品的埋藏地层为马兰黄土底部的洪积碎屑层,时代可能为晚更新世早期。苏家岭地点有1件石制品出自MIS3阶段弱古土壤层之下的洪积碎屑层,光释光年龄为距今7.2±0.7万年。其余大部分石制品的埋藏地层为马兰黄土层,时代为晚更新世中、晚期,其中凉泉沟地点埋藏石制品的黄土地层光释光年龄大于距今5万年。古人类加工石制品的原料主要为砾石,岩性以石英岩为主,其次为石英,此外还有少量燧石、细砂岩和硅质岩。石制品类型包括石核、石片、石器和断块。个体大小以中小型为主。石核和石片以自然台面者为主,剥片主要采用硬锤锤击法直接剥片,少量应用砸击法。石器有中小型的刮削器、凹缺器和大型的砍砸器,均属简单石核-石片技术产品。本次新发现的旧石器地点进一步扩大了晋陕峡谷地区旧石器时代遗存的时空分布范围,有助于后续相关研究工作的开展。  相似文献   
8.
It has been suggested that “double-wound” (bifilar) exposure coils are capable of producing a sham environment in which hum and vibration will be “similar” to the field-exposed condition. We found by direct measurements in a bifilar coil system that vibration amplitude in sham and exposed conditions differed by a factor of 50 when our test system was driven at B = 10 mT. We also found that the normal laboratory environment can include vibrations of an intensity similar to that produced by the exposure system, although not necessarily of similar spectral distribution. © 1996 Wiley-Liss, Inc.  相似文献   
9.
石料开发与获取是石器生产操作链的重要环节,也是史前人地关系研究的重要内容,能够反映史前人类的资源开发策略、环境认知与适应能力、移动模式和交流贸易网络等。相比于旧大陆西侧,东亚地区的燧石和黑曜岩等优质石料产地相对稀缺,中国许多旧石器考古遗址的石器原料主要来自遗址周边质量欠佳的脉石英、石英岩和一般燧石等,而相关的旧石器时代石料开发策略系统研究也相对较少。本文对中国目前已开展的旧石器时代石料开发策略研究进行系统梳理分析和总结发现,从旧石器时代早期到晚期末段,中国境内史前人类的石料开发策略存在明显的时空变化,主要体现在石料类型组成、产地选取和开发方式三个方面,可能主要受到史前人类流动性变化、石器技术演变和环境变化等因素的共同影响。综合而言,开展旧石器时代遗址的石料开发策略研究,对于理解中国境内史前人类的行为模式和交流迁徙等有重要意义。  相似文献   
10.
The open-air site of Kalavan 1 is located in the Aregunyats mountain chain (at 1640 m above sea level) on the northern bank of Lake Sevan. It is the first Upper Palaeolithic site excavated in Armenia. Led by an Armenian-French team, several excavations (2005–2009) have revealed a well preserved palaeosoil, dated to around 14,000 BP (years before present), containing fauna, lithic artefacts, as well as several hearths and activity areas that structure the settlement. The initial studies enable placement of the site in its environment and justify palaeoethnological analysis of the Epigravettian human groups of the Lesser Caucasus.  相似文献   
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