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Patricio López Isabel Cartajena Diego Carabias Carla Morales David Letelier Valentina Flores 《Archaeological and Anthropological Sciences》2016,8(2):277-290
Site GNL Quintero 1 (GNLQ1), located on the central coast of Chile, is the only documented Late Pleistocene drowned terrestrial site along the Pacific Coast of South America. Faunal evidence at the site is varied, and so far, remains of the following taxa have been found: extinct Camelidae, Cervidae, Equidae, Mylodontidae, Xenarthra, but also Myocastoridae, Canidae and Octodontidae. Both geological and paleoenvironmental data indicate that GNLQ1 developed in a floodplain or low-energy environment during the Last Glacial Maximum (LGM). Prior to the post-glacial rising of the sea level, the site would have been located several kilometres inland as the paleoshoreline was farther out on the continental shelf. In accordance with this background, the present study addresses the analysis of the spatial distribution of the bone deposits of GNLQ1 by considering both scenarios, the terrestrial phase related to the formation and modification of the fossil assemblage prior to the transgression, and the marine phase, subsequent to inundation. Results indicate modifications related to low-energy flow environment and carnivore activity dominated during the terrestrial phase and the action of marine organisms during the marine phase. Other taphonomic modifications are not easily attributable to either one or the other environmental context. 相似文献
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The Krafla geothermal system is located in Iceland's northeastern neovolcanic zone, within the Krafla central volcanic complex. Geothermal fluids are superheated steam closest to the magma heat source, two‐phase at higher depths, and sub‐boiling at the shallowest depths. Hydrogen isotope ratios of geothermal fluids range from ?87‰, equivalent to local meteoric water, to ?94‰. These fluids are enriched in 18O relative to the global meteoric line by +0.5–3.2‰. Calculated vapor fractions of the fluids are 0.0–0.5 wt% (~0–16% by volume) in the northwestern portion of the geothermal system and increase towards the southeast, up to 5.4 wt% (~57% by volume). Hydrothermal epidote sampled from 900 to 2500 m depth has δD values from ?127 to ?108‰, and δ18O from ?13.0 to ?9.6‰. Fluids in equilibrium with epidote have isotope compositions similar to those calculated for the vapor phase of two‐phase aquifer fluids. We interpret the large range in δDEPIDOTE and δ18OEPIDOTE across the system and within individual wells (up to 7‰ and 3.3‰, respectively) to result from variable mixing of shallow sub‐boiling groundwater with condensates of vapor rising from a deeper two‐phase reservoir. The data suggest that meteoric waters derived from a single source in the northwest are separated into the shallow sub‐boiling reservoir, and deeper two‐phase reservoir. Interaction between these reservoirs occurs by channelized vertical flow of vapor along fractures, and input of magmatic volatiles further alters fluid chemistry in some wells. Isotopic compositions of hydrothermal epidote reflect local equilibrium with fluids formed by mixtures of shallow water, deep vapor condensates, and magmatic volatiles, whose ionic strength is subsequently derived from dissolution of basalt host rock. This study illustrates the benefits of combining phase segregation effects in two‐phase systems during analysis of wellhead fluid data with stable isotope values of hydrous alteration minerals when evaluating the complex hydrogeology of volcano‐hosted geothermal systems. 相似文献
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EMPIRICAL STUDIES IN INDUSTRIAL LOCATION: AN ASSESSMENT OF THEIR METHODS AND RESULTS* 总被引:2,自引:0,他引:2
Josep‐Maria Arauzo‐Carod Daniel Liviano‐Solis Miguel Manjón‐Antolín 《Journal of regional science》2010,50(3):685-711
ABSTRACT This paper surveys recent evidence on the determinants of (national and/or foreign) industrial location. We find that the basic analytical framework has remained essentially unaltered since the early contributions of the early 1980s while, in contrast, there have been advances in the quality of the data (more firm and plant level information, geographical disaggregation, panel structure, etc.) and, to a lesser extent, the econometric modeling. We also identify certain determinants (neoclassical and institutional factors) that tend to provide largely consistent results across the reviewed studies. In light of this evidence, we finally suggest future lines of research. 相似文献
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Anna Sandak Jakub Sandak Magdalena Zborowska Włodzimierz Prądzyński 《Journal of archaeological science》2010
Archaeological wood, as most of natural materials, is slowly decomposing on the archaeological site due to various biological factors. Rapid and accurate estimation of the degradation level is extremely important for optimal restoration and conservation. The goal of this research was to verify the effectiveness of Fourier transform near infrared (FT-NIR) spectroscopy for archaeometry. The important advantage of the NIR spectroscopy is its accuracy, simplicity and ability to perform very high number of tests without needs of any destruction to the workpiece. Five oak pieces of the archaeological wood collected from waterlogged sites in Poland have been used. Cellulose and lignin contents, as well as crystallinity and the degree of polymerization were measured with standard reference methods and compared to the contemporary wood. The near infrared spectra represent all the physical/chemical changes of the wood due to waterlogging. This technique was successfully validated in rapid estimation of the cellulose and lignin contents. The method explored in this research might be a novel tool assisting experts in evaluation of the degradation state of archaeological and historical wooden materials. 相似文献
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Land fragmentation can be an important drawback for the development of rural areas. Due to the small size of the units, land management and planning are difficult from both the private and the public point of view. In some regions of Europe, land fragmentation can lead to the collapse of land-based activities such as agriculture and forestry. This process triggers land abandonment, which causes social, economic and environmental problems. Traditional interventions such as land consolidation have not worked because of the scale of land fragmentation, which leads to huge transaction costs. New planning instruments and governance structures for land management that balance the relations between property rights, management and labour force can be developed, in order to avoid the problems of land fragmentation. In this paper, we present two innovative examples of land management and governance structures for dealing with land fragmentation in rural areas of Galicia northwestern Spain. They were able to combine the use of individual and common property rights to make land use more sustainable, instead of trying to change land ownership. The new governance structures helped to increase efficiency and sustainability of the land use by, for example, increasing labour productivity, clarifying property rights and diminishing land abandonment. 相似文献
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Carmen López Sáenz 《European Legacy》2009,14(4):427-441
This essay examines how hermeneutic philosophy, particularly Gadamer's, recovers rhetoric, less as the art of speaking well than as a statement of a truth of the sensus communis, that which communicates veracious content through argumentation. This is the sense in which Gadamer acknowledges the ubiquity of rhetoric and hermeneutics as components of linguisticity (Sprachlichkeit). Conceived in the context of non-methodical wisdom and phronesis, Gadamer's rehabilitated rhetoric is concerned with pragmatics and ethics. Rhetoric is no longer viewed as a technique of verbal manipulation and becomes relevant for dialogic communication. Gadamer thus joins the Habermasian criticism of formalized reason that is detached from values. Both of them reject instrumental reason, because it has colonized communicational reason. However, since Gadamer's view of rhetoric has also been criticized by Habermas and Ricoeur their objections cannot be overlooked in a discussion of his hermeneutics. The essay concludes with a brief consideration of the implications of the debate on rhetoric, hermeneutics, and communication for the twenty-first century. 相似文献