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71.
During colonial times, an active maritime trade existed between Spain and the New World, with convoys sailing annually to and from Mexico and returning via Havana, Cuba, after wintering in America. A database constructed from secondary and open sources revealed that Spanish vessels were sailing over open waters along a northern path near Louisiana and a southern path across the central Gulf of Mexico. These routes were traversed in about one month and scheduling for the convoy was based on an understanding of the Americas’ meteorological and oceanographic climate. However, other factors may also have been involved in the directional layout of the routes. Today these ancient routes crisscross planning areas for oil and gas lease sales in the US Exclusive Economic Zone and the information presented in this article may aid in identifying areas where historic shipwrecks may lie. Maps and documents found during this study helped piece together the evolution of our understanding of the Gulf of Mexico surface circulation and how this knowledge influenced sailing during colonial times.  相似文献   
72.
During every war between Denmark and Sweden from at least 1505 to 1676 popular peace treaties were concluded by common men on both sides of the national border. These treaties were negotiated in contrast to the aggressive policy of the political leaders and to the nationalistic discourse of the elite. The aim of this article is to use archaeology to give an economic, social, and mental background to these treaties, and to the regional identity across the border that they presuppose. Above all a specific building tradition seems to have given the peasants a mental affinity across the border.  相似文献   
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The recording and 3D modelling of complex archaeological sites is usually associated with high capital and logistical costs, because the data acquisition must be performed by specialists using expensive surveying sensors (i.e., terrestrial laser scanners, robotic total stations and/or ground‐penetrating radar). This paper presents a novel, low‐cost, user‐friendly photogrammetric tool for generating high‐resolution and scaled 3D models of complex sites. The results obtained with unmanned aerial vehicle (UAV) photogrammetry of an archaeological site indicate that this approach is semi‐automatic, inexpensive and effective, and that it guarantees quality.  相似文献   
75.
In this work, we present the results of the characterization of 20 lime plaster samples taken from the Sacred Precinct of Tenochtitlan (Mexico City), the ancient capital of the Aztec empire. The samples come from different buildings of this precinct (A, B and D) and from the west façade of phase VI of the Templo Mayor pyramid. The objective of the work is to characterize the plaster samples, to understand the raw materials used, and to evaluate the presence of similarities and differences among the samples in the building techniques and raw materials employed. All the samples were studied with OM, SEM–EDS and LA–ICP–MS. The study provided evidence of the plastering and replastering practice in the same constructive phases. The results of the analyses showed the existence of important similarities and differences among buildings and constructive phases in the Sacred Precinct. In order to understand the provenance of the limestone used in the plasters, the lumps and the binder of the samples were analysed. The results were compared with those of the limestone outcrops located in central Mexico. The provenance study showed that all the limestone used in the construction of the analysed buildings of Tenochtitlan's Sacred Precinct comes from the Tula region.  相似文献   
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This paper evaluates the impact of accessibility on the productivity of Spanish manufacturing firms. We suggest the use of accessibility indicators of workers and commodities, integrating transport, land use, and individual components, computing real distances or traveling times using the Spanish full road network. Estimated firms’ total factor productivity is explained as a function of the accessibility indicators and additional control variables. Results evidence the crucial role on firms’ productivity to the accessibility of commodities and to a slightly lesser extent the workers.  相似文献   
78.
In north-western Patagonia, obsidian was used during the entire Holocene, and its importance increased with time. Recent fieldwork discovered a new obsidian source located in the Río Grande, which was called ‘Coche Quemado' (CQ). The results indicate that the CQ source has a different geochemical signal than all other sources in the region. Its use is spatially restricted to piedmont and, to a lesser extent, the plains. Chronologically, CQ was exploited in the middle and late Holocene, and its use accounts for a range of spatial distribution between 150 and 200 km.  相似文献   
79.
Particle-induced X-ray emission (PIXE), X-ray diffraction (XRD), electron microprobe analysis (EDS) and scanning electron microscopy (SEM) analytical techniques were used to characterize surface paints in pre- and post-fired Aguada Portezuelo decorated pottery. Surface paintings in black, white, red, brown, burgundy and ochre were analysed. Major, minor and trace elements were detected by PIXE, whereas XRD and SEM-EDS gave information on the main mineral phases and the characteristic morphology for each analysed pigment. The results obtained indicate that the main colour groups can be easily discriminated by PIXE, and they are characterized by only one pigment for each colour: hematite (red) and manganese mineral oxides (black), respectively, whereas white pigments are characterized by calcite, ghelenite and gypsum.  相似文献   
80.
Z. Nerudová 《Archaeometry》2020,62(2):410-426
This paper compares the quantification of different raw materials in a chipped stone assemblage by weight and by number at the site of Brno-Štýřice III in Moravia, Czech Republic. The use of the same reduction technology for all raw materials means that the Brno-Štýřice III assemblage is a good case study. The result demonstrates that semi-local raw material tends to dominate numerically, but in terms of weight, there is a significant change in the predominant raw material. The paper contextualizes the results in relation to other assemblages and discusses the possible reasons for this phenomenon.  相似文献   
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