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101.
D. T. POTTS 《Arabian Archaeology and Epigraphy》1991,2(2):138-144
Ties between the Nabataean area of northwestern Arabia and southern Palestine, and the northeastern portion of the Arabian peninsula have been discussed for some years. The material evidence of such ties is meagre, but nonetheless important. Two Nabataean coins from Thaj and one from Qatif are presented here, along with a painted Nabataean sherd from Thaj. Their implications are treated briefly. 相似文献
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Joseph R. Desloges 《The Canadian geographer》1990,34(2):98-109
Changes in the grain-size distribution and the lithologi-cal I mineralogical properties of sandy-gravel sediments are used to discriminate between sources for the alluvial valley-fill of Bella Coola River, coastal British Columbia. Spatially variable bedrock sources, ranging from highly resistant quartz monzonites to easily weathered basalts, yield sediments that reflect parent rock characteristics. Local increases in the D95 fraction of bulk gravel samples and the D50 fraction of sand samples can be related to inputs from steeper, heavily glaciated tributaries, or those underlain by fractured basalts of the Fraser Plateau. Where there are similarities in the grain-size properties of the source and the sampled deposit, however, grain-size information alone cannot be used to discriminate between sources. The lithology of Bella Coola alluvium shows a close correspondence with the general distribution of rock types in the basin, suggesting proportional contributions from most tributary sources over the long term. However, sand samples from the floodplain have a mostly volcanic affinity, indicating the dominance of sediment derived from headwater tributaries underlain by this rock type. Admixture of plutonic source sediments is evident in lower Bella Coola River adjacent to alluvial fans, heavily glaciated tributary creeks or rock walls comprised mainly of quartz monzonite. Les changements dans la granulometrie et les proprietes lithologiques et mineralogiques des sediments de gravel sablonneux servent d differencier les sources des depéts alluviaux de la Riviere Bella Coola sur la céte de la Colombie-Britannique. La variation spatiale des sources fondamentales donnent des sediments qui refletent les caracteristiques de la roche-mbe variant des quartz rnonzonites très résistants aux basaltes superficiellement altérés par les agents atmospheriques. Les augmentations locales dans la fraction D95 des echantillons de gravel et la fraction D50 des echantillons de sable peuvent être reliees la contribution des tributaires aux pentes plus escarpees et fortement glaciaires ou ceux qui traversent les basaltes fractures du Plateau Fraser. Cependant, quand il y a des similitudes dans la granulometrie de la source et le dépôt-échantillon, l'information granulometrique seule ne peut pas 6tre employee pour differencier les sources. La lithologie des alluvions de Bella Coola montre une correspondance avec la distribution générale des types de roches dans le bassin, suggérant des contributions proportionnelles des sources tributaires a long terme. Cependant, les échantillons de sable des plaines sujettes à inondations ont en grande part une affinité volcanique, indiquant que la dominance du sédiment provient des tributaires qui traversent ce type de roche. Une addition de sediments de sources plutonique est evidente dans le bas de la Riviere Bella Coola adjacent aux eventails alluviaux, aux ruisseaux tributaires affect& par une forte glaciation, ou aux murs de roches qui comprennent principalement des quartz monzonites. 相似文献
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Non‐invasive materials characterisation of reconstructed statues of Emperor Qin Shihuang's Terracotta Army has revealed distinct micro‐geochemical patterning within the clay paste used in their manufacture. The significance of this is explored in terms of the production sequence, logistics and supply‐chain management involved in the construction of this enormous funerary assemblage. Of particular interest is a compositional distinction between figures marked with the names ‘Gong’ (宫) and ‘Xianyang’ (咸阳). These seem to represent the products of two workshops involved in the supply of ceramic objects for this ambitious, large‐scale building project undertaken by the Qin Empire during the third century bce . 相似文献
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Rusudan Chagelishvili George Jaoshvili Jimsher Chkhvimiani Hamed Al Mutairi 《Arabian Archaeology and Epigraphy》2021,32(1):141-151
Kuwait–Georgian archaeological work at Failaka Island showed the need for geological study. Analysis of sediments related to drinking water-collecting cisterns was performed on a Late Islamic settlement (NE part of the island) in 2018. Field sedimentological, grain size and XRD analysis of the sediment profiles showed that the shallow (about 1 m deep) cone-shaped wells are dug in the loose, porous, cross-stratified calcareous coarse-grained quartz sandstones. Three upper layers of quartz sandstones in the profile have high infiltration rate and provide a rare yet ideal material for water retention. The fourth dense layer below, composed of very fine sand and silt fraction, tends to hinder water movement and forms a relatively impermeable water-resistant surface. Thus, the distribution patterns of clay content, grain sizes and porosity of the well-hosting sediments are favourable for freshwater infiltration and harvesting. An additional petrographic analysis was conducted on different types of rocks discovered on the archaeological site, used as building material and fragments of stone artifacts to identify their origin. It was established that archaeological building material is of local origin, whereas the source rocks for stone artifacts were imported. 相似文献
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Damiaan Persyn Javier Barbero Jorge Díaz-Lanchas Patrizio Lecca Giovanni Mandras Simone Salotti 《Journal of regional science》2023,63(4):755-792
We analyze the general equilibrium effects of an asymmetric decrease in transport costs, combining a large-scale spatial dynamic general equilibrium model for 267 European NUTS-2 regions with a detailed transport model at the level of individual road segments. As a case study, we consider the impact of the road infrastructure investments in Central and Eastern Europe of the European Cohesion Policy. Our analysis suggests that the decrease in transportation costs benefits the targeted regions via substantial increases in gross domestic product (GDP) and welfare compared to the baseline, and a small increase in population. The geographic information embedded in the transport model leads to relatively large predicted benefits in peripheral countries such as Greece and Finland, which hardly receive funds, but whose trade links cross Central and Eastern Europe, generating profit from the investments there. The richer, Western European nontargeted regions also enjoy a higher GDP after the investment in the East, but these effects are smaller. Thus, the policy reduces interregional disparities. There are rippled patterns in the predicted policy spillovers. In nontargeted countries, regions trading more intensely with regions where the investment is taking place on average benefit more compared to other regions within the same country, but also compared to neighboring regions across an international border. We uncover that regions importing goods from Central and Eastern Europe enjoy the largest spillovers. These regions become more competitive and expand exports, to the detriment of other regions in the same country. 相似文献