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991.
Ancient cultures have a wide range of water control management techniques, each associated with a particular purpose, including water for consumption, agriculture, flood control, drought relief, and rituals (Scarborough, 2003). One technique that has received limited archaeological attention is the purposeful creation of water pressure to perform useful work. Perhaps the earliest such example was found on the island of Crete in a Minoan palace and dates as early as 1400 BC. Terracotta pipe segments with graded diameter reductions were used to create fountains (Evans, 1921–1935). Although gravity and the weight of water are the most efficient means of generating water pressure in a closed conduit, natural conditions (climate, geology, topographic slope, etc.) that might lead to the construction of water pressure systems are less clear. Here we show that the Classic Maya (AD 250–600) constructed a water pressure system with the potential to control the flow of water within an urban area. By burying a conduit along a steep ephemeral channel passing through a residential group, upland springs could be diverted to build pressure in the conduit to provide a dry-season supply of water. Up to 6 m of hydraulic head could have been recovered to lift water from the pressurized conduit to a point of use. Water pressure systems were previously thought to have entered the New World with the arrival of the Spanish. Yet, archaeological data, seasonal climate conditions, geomorphic setting, and simple hydraulic theory clearly show that the Maya of Palenque in Chiapas, Mexico had empirical knowledge of closed channel water pressure predating the arrival of Europeans. 相似文献
992.
J. Sanjurjo-Sánchez M.J. Trindade R. Blanco-Rotea R. Benavides Garcia D. Fernández Mosquera C. Burbidge M.I. Prudêncio M.I. Dias 《Journal of archaeological science》2010
Bulk samples of mortars from the Santa Eulalia de Bóveda temple (NW Spain) have been characterized from a chemical and mineralogical point of view, with the aims of contributing technological and provenance inferences, and evaluating possible correlations with the various identified stages along historical periods of construction. 相似文献
993.
This paper deals with some of the hydraulic structures of Augusta Emerita (Mérida, Spain), specifically those found in the Mithraeum House. In particular, we describe and characterise the hydraulic mortars and coatings of the viridarium water channel. The recipient of the channel was covered with two hydraulic mortars and a finishing coating. Hydrated lime was used as binder. Calcite grains with different morphology have been observed in the mortars studied. The siliceous aggregate was composed of quartz, mica and feldspars. Ceramic fragments, which were added to the mortar to improve its hydraulic properties, were composed of quartz, mica, iron oxides, anorthite and an amorphous phase; aluminium-iron silicates were used as raw materials for their manufacture. We discuss the interactions between the hydrated lime and the surface of the ceramics in the mortars. 相似文献
994.
Recent investigations at the prehistoric Purrón Dam Complex in the Tehuacán Valley of southern Puebla, México applied radiometric dating to more securely date the complex. Ceramic-based dating in the 1960′s placed the Dam's origin to the Formative Period. While Formative Period origins are widely accepted, the chronology lacks resolution and direct dates. Samples from impounded sediments behind the dam and from prehistoric canal fill were dated through Optically Stimulated Luminescence (OSL) as well as both standard 14C and accelerated mass spectrometry (AMS) assays. These samples directly date the functioning of the water management features within the complex. The results confirm the Formative Period origins of the Purrón Dam, and offer new insights into the construction and functioning of the dam and irrigation system. 相似文献
995.
To continue to explore the impact of past human activity on the stable nitrogen isotope ratios of modern vegetation, we have measured the δ15N values of plants now growing on several ancient farmsteads in the Western Settlement of Norse Greenland. Although this new test area is some 400 km north and in a different ecoregion from the previous study area, the same isotopic effect was observed. A clear isotopic signature was found on the ancient farms which could be directly correlated to past activity areas; in particular, the infields. Further, the magnitude of the δ15N values was found to be similar between study areas, indicating the same interpretative framework can be applied in widely separate geographic regions. A first test of different plant species showed that although the magnitude differed greatly the same basic information was found for functionally different plants. These observations provide additional information to aid in future archaeological application of this newly observed phenomenon. 相似文献
996.
Serin D. Houston D. James McLean Jennifer Hyndman 《Gender, place and culture : a journal of feminist geography》2010,17(1):61-79
This article mobilizes a feminist analytic to examine team research and collaborative knowledge production. We center our encounter with team research – a collectivity we named ‘Team Ismaili’ – and our study with first- and second-generation East African Shia Ismaili Muslim immigrants in Greater Vancouver, Canada. We draw upon feminist politics to highlight the ways in which ‘Team Ismaili’ at once destabilized and unwittingly reproduced normative academic power relations and lines of authority. A ‘backstage tour’, of ‘Team Ismaili’ shows the messiness and momentum of team research and sheds light on how collaborative knowledge production can challenge and reconfirm assumed hierarchies. Even as we are still methodologically becoming, through this discussion we strive to interrupt the prevailing silence on team research in human geography, to prompt more dialogue on collaboration and to foreground the insight garnered through feminist politics. 相似文献
997.
998.
A cylinder seal of Late Uruk (late fourth millennium BC) type from Abu Dhabi is presented and analysed. Comparisons with excavated finds from elsewhere in the Near East are discussed. An inventory of cylinder seals from sites in the UAE and the Sultanate of Oman shows that cylinder seal use, while not unknown in the region, was never very great. The ways in which the seal may have arrived at its eventual place of discovery are described and the significance of the seal is assessed. 相似文献
999.
Maria Anna Pabst Ilse Letofsky-Papst Maximilian Moser Konrad Spindler Elisabeth Bock Peter Wilhelm M.D. Leopold Dorfer Jochen B. Geigl Martina Auer Michael R. Speicher Ferdinand Hofer 《Journal of archaeological science》2010
From a 1000-year-old mummy, found unwrapped in the sand of the desert at Chiribaya Alta in Southern Peru, two different kinds of tattoos were investigated: decorative tattoos displaying different animals and symbolic ciphers were present on the extremities and tattooed circles on the neck region. 相似文献
1000.
Karen D. Lupo 《Journal of Archaeological Method and Theory》2006,13(1):19-66
This paper uses rationale derived from central place foraging models to explore the factors that guide the carcass processing and transport decisions of modern hunters. Using data derived from butchering experiments, I test different economic indices that purportedly reflect the field processing and transport decisions of contemporary African Hadza hunter-gatherers. The results show that no single index predicts part processing and transport for the species examined in this analysis. Processing and transport decisions are, however, patterned in ways that are consistent with theoretical predictions. While similar processes likely guide carcass treatment and transport decisions among all hunter-gatherers, different ecological, social, and historical constraints define the range of solutions to problems involving carcass treatment. In this specific example, intertaxonomic differences in carcass size and bone properties constrain how the trade-offs between field processing and transport costs are resolved. I conclude by suggesting ways in which analysts might make use of central place foraging rationale and models to explain variation in skeletal representation and abundances across time and space.
相似文献
Karen D. LupoEmail: |