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961.
The volcanic millstones from the archaeological site of Morgantina (Sicily): provenance and evolution of the milling techniques in the Mediterranean area*
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The Morgantina archaeological area, inhabited from the Early Bronze Age, had its widest expansion from the fifth to the first century bc . The volcanic millstones found at Morgantina fall into three different groups on the basis of the milling technique: (i) saddle querns (known from the Middle–Late Bronze Age and Iron Age); (ii) rectangular hopper‐rubbers (Olynthian) millstones, the invention of which dates to the fifth century bc ; and finally (iii) Morgantina‐type rotary millstones (starting to be used from the fourth to the third century bc ). In order to determine the provenance of the raw materials (lavas) used for all these millstone types, we collected 38 very small rock samples for thin‐section modal mineralogy, petrography and major trace element composition. The results have contributed to classifying different lithotypes and distinguishing between provenance from Etna and the Hyblean Mountains, the two volcanic areas respectively north‐east and south‐east of Morgantina. Saddle querns are made of tholeiitic basaltic andesites from the Hyblean Mountains and transitional basalts, mugearites and hawaiites from Etna. The variety of sources of portable saddle querns, mostly used in households, indicate that there was no general preference for specific quarrying sites. By contrast, the rectangular hopper‐rubber and the Morgantina‐type millstones, which document the period of Morgantina's greatest prosperity, are almost completely made of hawaiites from Etna. The use of a specific lithotype (i.e., Etna hawaiite) for the more efficient rectangular hopper‐rubber and rotary millstones could be linked to the fact that these mills may have been operated in business establishments. It is worth noting that the Gornalunga river was, in antiquity, a waterway joining Morgantina to the final stretch of the Simeto river and then the Ionian coast. The best candidate areas for the millstone hawaiite quarrying sites from Etna are the far south‐western sectors of the volcano, along the Simeto Valley (i.e., the ‘Piano Provenzana’ Formation) or the inner suburb of present‐day Catania (i.e., the ‘Pietracannone’ Formation). The very efficient Morgantina‐type rotary millstones spread during the reign of Hieron II of Syracuse (275–215 bc ) in eastern Sicily and met the need for grinding large quantities of cereals during a relatively peaceful time and a period of agricultural development. 相似文献
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AbstractIn the Pacific islands, subsistence diversity made possible continuous production of food while well-developed exchange networks redistributed these foodstuffs as well as items within the prestige economy. All these were aspects of the ‘storage structures’ that enabled social and nutritional value to be saved, accumulated and later mobilised. In addition, there were investments in the land, landesque capital, which secured future food surpluses and so provided an alternative to food storage, in a region where the staple foods were mostly perishable, yams excepted, and food preservation was difficult. Landesque capital included such long-term improvements to productivity as terraces, mounds, irrigation channels, drainage ditches, soil structural changes and tree planting. These investments provided an effective alternative to food storage and made possible surplus production for exchange purposes. As an example, in the New Georgia group of the western Solomon Islands irrigated terraces, termed ruta, were constructed for growing the root crop taro (Colocasia esculenta). Surplus taro from ruta enabled inland groups to participate in regional exchange networks and so obtain the shell valuables that were produced by coastal groups. In this paper, we reconstruct how this exchange system worked in New Georgia using ethno-archaeological evidence, we chart its prehistoric rise and post-colonial fall, and we outline the factors that constrained its long-term expansion. 相似文献
966.
Oriol Caselles Guillermo Martínez Jaume Clapés Pere Roca Maria de la Vega Pérez-Gracia 《International Journal of Architectural Heritage》2015,9(3):310-323
Determining the behavior of a structure estimated by means of finite elements analysis requires not only an in-depth knowledge of its geometry and dynamic properties but also an experimental validation to corroborate the adequacy of the characteristics of the structure. Most of the current structural identification techniques are based on linear methods that call for many measurement points and/or a relative simple structure. Complex structures are somewhat still an unexplored field due to the difficulties with the finite element method and the experimental corroboration of its results. This study presents the use of particle motion computation applied to each structural vibration mode to improve the identification of its dynamic properties, and its application to the Gothic Cathedral of Palma de Majorca (Spain). 相似文献
967.
Luís Mateus Maria do Rosário Veiga 《International Journal of Architectural Heritage》2015,9(4):430-442
The Algarve region in southern Portugal has one of the most significant rammed earth construction legacies in the country. This construction method is characterized by its high susceptibility to water damage and external renderings are essential to the longevity of these constructions. This study collects and organizes data that provides the basis for the conservation and repair of renderings. Five earth buildings from western Algarve were selected to represent this heritage and its diversity of composition and susceptibility to water damage. Some of their commonest anomalies result from the interaction between the earth substrate and the traditional external renderings, given their distinct characteristics and behavior. The selected sample is described and the mechanical strength of the rammed earth walls and their renderings are evaluated through in situ tests. Samples of the external renderings and earth substrate of the five buildings comprising the sample were also collected and characterized in the laboratory. The characteristics of these two materials and their behavior as an assembly were analyzed. The results of the in situ and laboratory tests are compared and the viability of using a method based on in situ tests for the wider characterization of the type of construction under analysis evaluated. 相似文献
968.
In delivering public policy, governments worldwide increasingly partner with diverse sets of stakeholders. This spreads commercial risk, but particularly where agendas diverge, introduces new risks related to trust in relationships. The “risk hypothesis” distinguishes between networks for “cooperation” problems, where partners have high individual payoffs for uncooperative behaviors, and “coordination” problems, where partners subscribe to a common goal and uncooperative behaviors are less rewarding. We used mixed‐methods to study networks of local and state government, developers, and consultants that center on joint‐venture partnerships for developing new urban, residential projects. Statistical network methods showed that within the mix of partners involved in development projects, only state governments displayed structural patterns associated with solving “cooperation” problems (rather than coordination). In other words, the patterns of state government interactions showed they are most exposed to risky relationships. In contrast to the state governments’ apparent exposure to risk, qualitative data showed they are not only well trusted but also overall the partnership networks reported very low levels of conflict. By exploring the distribution of “cooperation” and “coordination,” we identified which stakeholders perceived most risk. In our case, how the state governments’ structure interactions in response to risky relationships leads to an overall network characterized by trust. 相似文献
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970.
In this paper, we present a paleodemographic interpretation of a complete mortuary population from the site of Rio Muerto (southern Peru) affiliated with the early Andean Tiwanaku state (A.D.500–1000). Although advances in biogeochemical paleomobility studies have revolutionized bioarchaeological approaches to certain aspects of migration, paleodemography continues to offer a valuable complementary perspective on migration and population dynamics. Notably, paleodemography, through reference to Uniformitarian age‐at‐death profiles, is uniquely equipped to identify age‐specific subgroups that are missing from the mortuary population. We argue that the marked absence of adult individuals in the M70B cemetery population is the result of the socially regulated movement of older adults or their remains from the state provinces back to the homeland. We suggest that the particular demographic composition of the Rio Muerto M70 cemetery population, when considered within its cultural context and compared to other available paleodemographic data, reveals potential patterns of adult return migration, and carries important implications for the political and social dynamics of early Andean state society. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献