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1.
Abstract

Corrosion modelling of decay rates of the iron wrecks in Port Phillip Bay, Victoria, has enabled an estimation of the speed at which the historic resource of iron shipwrecks is disappearing. Use of the significance ranking of the iron wrecks, based on the Australian National Standards for significance assessment, provides a useful guide to decision-making, but decisions based solely on these criteria can lead to less than optimal results. From the corrosion rates and the amount of residual metal thickness in structural elements it is possible to determine a conservation ranking that is based on the need for intervention and the chances of being successful in stabilizing the wrecks. The arithmetic product of the significance and conservation rankings defines the treatment score or ranking which forms the basis for rational decision making about deployment of resources.  相似文献   
2.
This study presents the results of multi-element analysis of weak-acid extractions of 953 soil samples collected by coring on and around pre-historic village sites on two islands, Sanak and Amaknak, in the eastern Aleutians. Concentrations of aluminum (Al), barium (Ba), calcium (Ca), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), phosphorus (P), strontium (Sr), titanium (Ti), and zinc (Zn) were determined using an inductively coupled plasma-mass spectrometer (ICP-MS). Resultant elemental signatures allow the identification of site features and organization in the absence of large-scale excavation. All the archeological sites showed similar and distinct chemical signatures regardless of the several thousand year date range of the sites or the length of time a site was occupied. However, intensity of occupation does appear to affect concentrations of elements. Site features such as houses, house berms, house floors and middens had distinct anthropogenic signatures and could be distinguished from one another. This approach may be used to identify sites that do not have distinct surface features and to target areas for excavation.  相似文献   
3.
出土青铜酒器残留物分析的尝试   总被引:2,自引:1,他引:2  
利用快速溶剂萃取法,从出土青铜酒器内的土壤中提取有机残留物.对其作高效液相色谱定性分析,发现其中含有酒石酸,表明这些青铜酒器在下葬时可能盛着酒。快速溶剂萃取法的萃取剂为1%磷酸(体积比)溶液,较之传统有机溶剂,操作时更为方便和安全。此方法可推广于陶器中残留物的分析.具有较为广泛的应用前景。  相似文献   
4.
    
The Iron Age settlements of northern Cameroon were dispersed across the landscape, taking advantage of different eco-climatic zones to exploit a variety of natural resources. Situated at the interface of the upper and lower terraces of the Benue River, mound sites in the area around Garoua have occupation histories spanning multiple centuries. The site of Langui-Tchéboua displays evidence for rapid accumulation of sediments approximately 700 years ago, which may have been a deliberate construction strategy that would have allowed the site’s inhabitants to exploit resources in both floodplain and dryland contexts. The combined use of multiple dating methods and micromorphology provide novel insights into both the mechanisms of anthropogenic landscape change and possible motivations governing those choices.  相似文献   
5.
    
The purpose of this study is to derive the attenuation relationships for PGA, PGV, and EPA parameters for areas within the seismic zones of Zagros, Alborz and Central Iran with rock and soil substructures. In order to do so, at first the available scientific data including the methods used for deriving attenuation relationships and the parameters involved have been gathered. Afterwards, all the efforts have been focused on gathering a thorough catalogue of earthquakes occurred in Iran. In this regard, a majority of the available catalogs in Iran have been gathered and corrected through different methods and finally a set of 89 earthquake events including 307 earthquake records with reliable data was chosen.

Since in order to derive the attenuation relationships it is essential to extract the parameters from the acceleration records, a great effort was placed on gathering the earthquake acceleration records of Iran. This resulted in building a database of a majority of the earthquake records up to the year of 2004. Afterwards, correction methods applicable to earthquakes records of Iran considering the type of machines used and the ground type were examined which resulted in certain guidelines for correction of earthquake acceleration record data related to Iran.

In the next step the needed parameters were extracted from the earthquake acceleration record data which were consequently divided into two seismic zones of Zagros, and Alborz and Central Iran according to tectonic conditions. After examination of the parameters and choosing the most appropriate among them, the attenuation relationships were derived for such parameters.  相似文献   
6.
Environmental archaeology methods can uncover both house lot organization and economic adaptation practices when applied systematically in conjunction with traditional archaeological research. This is the first study to employ both phytolith analysis and soil chemistry to interpret activity areas on an archaeological site. The patterning in the phytolith and soil chemistry analyses from the site of Rich Neck Plantation, Williamsburg, Virginia, reveals a set of six activity areas in and around the 17th century house lot, demonstrating a degree of economic diversification generally attributed only to 18th century colonial economic and social transformations.  相似文献   
7.
The aim of this study was to apply Nakamura's technique to Valencia city center, after some preliminary tests in Barcelona. Previous studies of Barcelona had measured periods in restrictive conditions and in various types of material ranging from very soft soil (with a predominant period of approximately 2 s) to rock (0.3 s), and under different measurement conditions. The Valencia city center measurements were taken by using the distance from buildings and car and pedestrian traffic to construct a measurement grid that was as regular as possible. We also estimated possible soil-structure interaction to detect potential vulnerability.  相似文献   
8.
This work was aimed at developing a practical and simple settlement estimation of shallow foundation on liquefiable deposits. The study conducted a centrifuge test, a series of comprehensive numerical analysis, back analysis, equation calibration, and verification with data from not only centrifuge test but also the literature. It finally proposed a quick calculation method based on Meyerhof’s settlement equation (1965). A two-dimensional numerical analysis, named ALID, (Analysis for Liquefaction-induced Deformation), was employed for obtaining settlement of shallow foundations on liquefiable soils with different relative densities under various seismic conditions. Its performance was first verified through a centrifuge test conducted in this study. Then, the developed method based on Meyerhof’s settlement equation was employed, and a new parameter, NLR, was proposed to present the strength of liquefied soils by replacing N value in the original equation. The NLR was obtained through back analysis of the numerical results and modified accordingly after comparison with the data from the literature. This paper, finally, demonstrated the practical use of the proposed method involving NLR by predicting 199 sets of liquefaction-induced settlement of shallow foundation reported in the past, including a latest most liquefaction-induced settlement of a house in 0206 earthquake on February 6, 2016, in Taiwan.  相似文献   
9.
Analysis of detailed geomorphological mapping enables a sequence of glacial events to be established. An ice sheet whose source was to the west of the area of study is shown, by the suites of fluvioglacial landforms produced, to have down‐wasted in situ; meltwaters escaped beneath or through the ice, moving uphill across certain areas. Finally, a sub‐aerial drainage system was established and outwash terraces were spread down valley.  相似文献   
10.
This study presents the application of multi-element soil analyses (X-ray fluorescence spectroscopy and inductively coupled plasma optical emission spectroscopy of 1 M HCl extracts) to grid samples from 3 archaeological house plans embedded in sandy clays, clays and sands to assess effects of site lithology on geochemical signatures of human occupation.  相似文献   
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