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1.
Pearls have been a valued resource in most cultures that had access to them. A number of historically important pearling grounds were situated in the waters around today's Indonesia. One of these areas, now largely forgotten, was the Segara Anakan lagoon in South Java. In the seventeenth century, Dutch colonists exploited the lagoon's pearls. Afterwards, the lagoon's oysters were locally exploited as a food item until the late 1970s. While the pearl fishery attracted considerable attention in the colonial literature, its disappearance, by contrast, went largely undocumented. Nowadays, the oysters no longer are found in the lagoon as a result of extensive sedimentation processes. Their former existence is only preserved in the memory of local people. This article examines the history and fate of the pearls of Segara Anakan, providing an example of a formerly valued species whose existence simply became forgotten outside the area.  相似文献   
2.
Pronghorn (Antilocapra americana) fetal remains are sometimes recovered from archaeological contexts. Pronghorn have consistent reproductive schedules so their remains may provide information on seasonality of site occupation and number of mortality events. To investigate the reliability of fetal remains for seasonality and mortality event assessment, bone size and tooth eruption were measured in a sample of modern fetal pronghorn remains with known mortality dates. Results indicate a strong correlation between bone size and mortality date, but no significant correlation between tooth eruption level and mortality date. Fetal bone size was used to estimate a late April or early May mortality date at both the Oyster Ridge (48UT35) and Trappers Point (48SU1006) archaeological sites. The number of mortality events at Trappers Point was also investigated. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
3.
The Velykyi Glybochok Palaeolithic site near Ternopil town (Podolia Upland) contains a set of cultural layers in a sequence of loess and fossil soils. Beside the archaeological study of stone assemblages, the profile was investigated using lithological, palaeopedological and geochemical methods, including stable carbon and oxygen isotopes composition of pedogenic carbonates, soils micromorphology and TL dating. Remnants of vertebrates' bones and mollusc shells were also distinguished. The oldest cultural layer III documented the presence of Palaeolithic people during the Penultimate Interglacial represented by fossil soil – cambisol in type, developed under dense vegetation cover. The cultural layer III B is connected with initial cambisol originated in a short period of open landscape vegetation with shrubs development, dated to the climatic amelioration during the time of Penultimate Glaciation. The Last Interglacial is represented by luvisol formation with two stages of illuviation, which shows forest type of vegetation. Materials of the cultural layer III A were dispersed in the soil irregularly and mixed with artifacts of cultural layer II. Artifacts of III, III A and III B cultural layers represent the Middle Palaeolithic “Dniesterian Mousterian culture with Levalloisian technique”. These of assemblage II represent the Upper Palaeolithic. Inside the recent soil at the top of the sequence, the Mesolithic cultural layer I is present. Velykyi Glybochok is the only multilayer site in Podolia with detailed information about geological position of particular cultural layers.  相似文献   
4.
Numerical site response analyses were carried out on the Nicastro ridge in Southern Italy in order to investigate topographic effects. First, the analyses were carried out on a simplified model by employing simple artificial signals, in order to get preliminary physical insights into the two-dimensional phenomena involved. Then, numerical analyses were carried out on a more realistic heterogeneous subsoil model developed on the basis of geotechnical and geophysical investigations. Real accelerograms were selected for these analyses. Particular attention was devoted to separating topographic from stratigraphic amplification. Finally, the topographic amplification factors were compared with literature data and Eurocode 8 recommendations.  相似文献   
5.
为考证泉州“蚵壳厝”牡蛎壳的来源,本文利用了动物学、动物地理学知识对“蚵壳厝”所用的牡蛎壳进行了种类鉴定和分布的分析。结果显示:“蚵壳厝”的牡蛎壳由大量近江牡蛎(CraSS0Strear1Vu一]ar1S)和少量的长牡蛎(C.g1gaS)组成,这两种牡蛎都属巨牡蛎属(CraSS0strea)。动物地理学特点显示,它们都是分布在太平洋一印度洋交汇海域,东非沿海的印度洋西部并没有这些种类的分布。结合前人对海上丝绸之路的研究结果,我们认为泉州“蚵壳厝”牡蛎壳应该是来自于东南亚或南海北部沿海。  相似文献   
6.
In the now burgeoning scholarship on memory, there is a discernible shift from considering the politics of dominant public memory towards sites of counter-memories where vernacular forms of memory activism take place. This paper contributes to this by focusing its attention on plans to preserve Green Ridge in Kampar, Malaysia, a tract of forested hill that was the location of a fierce battle fought between the Japanese and Allied forces in the Asia-Pacific theatre of the Second World War. Specifically, it details the rescaling strategies of one particular individual to enhance the reach and relevance of the site for Malaysians writ large, primarily aimed at lobbying for Green Ridge to be officially marked as local and national heritage. This paper then interrogates issues that have hindered this process with the potential to ultimately thwart the preservation of the site for posterity. In doing so, the paper exemplifies memory activism as ‘work’, where local actors–through the mobilisation of scale politics–represent proactive agents in effecting change in public memory from below. Second, it highlights the fragmented nature of vernacular remembering and how this can impede memory work as much as champion memory formally obscured.  相似文献   
7.
中国古建筑中几种石灰类材料的物理力学特性研究   总被引:4,自引:1,他引:3  
为探讨适宜于岩土文物保护加固的石灰类材料,对中国古建筑中几种石灰类材料及欧洲水硬石灰的化学组成和物理力学特性进行对比研究。研究表明烧料礓石、烧阿嘎土、欧洲水硬石灰NHL5及改性捶灰的化学组成主要是气硬性胶凝材料石灰CaO(或Ca(OH)2)和水硬性胶凝材料β-硅酸钙(β-CS)及铝硅酸钙(CAS),并且这些材料的结石体具有大的孔隙率及非常小的收缩变形性等特点,适宜于岩土文物的保护加固。除此之外,石灰、糯米灰浆、蛎灰、传统捶灰的主要化学组成为石灰CaO(或Ca(OH)2),实验研究结果显示,浆液的凝固速度慢,弹性波速小且上升速率慢,结石体虽然孔隙率大,但强度在短期内较低,易产生收缩变形,不适宜用于短时间内有强度要求的岩土文物保护加固,所以有必要对蛎灰和传统捶灰做进一步的改性研究,以便更广泛地应用于岩土文物的保护加固中。  相似文献   
8.
The late Archaic Soapstone Ridge quarries, near Atlanta, Georgia, are the largest sources of archaeological soapstone in the south‐eastern USA. Ten soapstone artefacts from the coastal plain, over 200 km south of Soapstone Ridge (SSR), were used in an attempt to relate their mineralogy to that of the Soapstone Ridge quarries and to investigate the utility of mineralogy in the sourcing of soapstone. There is an overall similarity in the abundance of the major soapstone minerals, talc, chlorite and amphiboles in the artefacts and the SSR soapstone. Differences in the variety of amphibole (tremolite/actinolite, magnesiohornblende and magnesiocumingtonite/anthophyllite) and FeTi oxides (magnetite and ilmenite) eliminate SSR as a source for some of the artefacts. The compositions of chlorite (Cr), magnesiohornblende (Si, Al) and Fe oxides (Cr, Mn) in other artefacts are not consistent with a Soapstone Ridge source. The talc compositions are identical in the artefacts and the SSR soapstone. The mineral assemblage and compositions of two artefacts are consistent with a Soapstone Ridge source. Despite an overall similarity in the modal mineralogy of the artefacts and Soapstone Ridge quarries, there is enough diversity to distinguish between artefacts from Soapstone Ridge or some other source. Mineralogy is a useful tool for the evaluation of soapstone sources.  相似文献   
9.
The Lost City hydrothermal field (LCHF) is hosted in serpentinite at the crest of the Atlantis Massif, an oceanic core complex close to the mid‐Atlantic Ridge. It is remarkable for its longevity and for venting low‐temperature (40–91°C) alkaline fluids rich in hydrogen and methane. IODP Hole U1309D, 5 km north of the LCHF, penetrated 1415 m of gabbroic rocks and contains a near‐conductive thermal gradient close to 100°C km?1. This is remarkable so close to an active hydrothermal field. We present hydrothermal modelling using a topographic profile through the vent field and IODP site U1309. Long‐lived circulation with vent temperatures similar to the LCHF can be sustained at moderate permeabilities of 10?14 to 10?15 m2 with a basal heatflow of 0.22 W m?2. Seafloor topography is an important control, with vents tending to form and remain in higher topography. Models with a uniform permeability throughout the Massif cannot simultaneously maintain circulation at the LCHF and the near‐conductive gradient in the borehole, where permeabilities <10?16 m2 are required. A steeply dipping permeability discontinuity between the LCHF and the drill hole is required to stabilize venting at the summit of the massif by creating a lateral conductive boundary layer. The discontinuity needs to be close to the vent site, supporting previous inferences that high permeability is most likely produced by faulting related to the transform fault. Rapid increases in modelled fluid temperatures with depth beneath the vent agree with previous estimates of reaction temperature based on geochemical modelling.  相似文献   
10.
Fluid chemistry and microbial community patterns in chimney habitats were investigated in two hydrothermal fields located at the Central Indian Ridge. Endmember hydrothermal fluid of the Solitaire field, located ~3 km away from the spreading center, was characterized by moderately high temperature (307°C), Cl depletion (489 mm ), mildly acidic pH (≥4.40), and low metal concentrations (Fe ≤ 105 μm and Mn = 78 μm ). Chloride depletion indicates that the subseafloor source fluid had undergone phase separation at temperatures higher than ~390°C while the metal depletion was likely attributable to fluid alteration occurring at a venting temperature of around 307°C. These different temperature conditions suggested from fluid chemistry might be associated with an off‐spreading center location of the field that allows subseafloor fluid cooling prior to seafloor discharge. The microbial community in the chimney habitat seemed comparable to previously known patterns in typical basalt‐hosted hydrothermal systems. Endmember hydrothermal fluid of the Dodo field, standing on center of the spreading axis, was characterized by high H2 concentration of 2.7 mm . The H2 enrichment was likely attributable to fresh basalt–fluid interaction, as suggested by the nondeformed sheet lava flow expansion around the vents. Thermodynamic calculation of the reducing pyrite–pyrrhotite–magnetite (PPM) redox buffer indeed reproduced the H2 enrichment. The quantitative cultivation test revealed that the microbial community associated with the hydrothermal fluid hosted abundant populations of (hyper)thermophilic hydrogenotrophic chemolithoautotrophs such as methanogens. The function of subseafloor hydrogenotrophic methanogenic populations dwelling around the H2‐enriched hydrothermal fluid flows was also inferred from the 13C‐ and D‐depleted signature of CH4 in the collected fluids. It was observed that the hydrothermal activity of the Dodo field had ceased until 2013.  相似文献   
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