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71.
A reactive transport computer code has been employed to model hydrothermal alteration of a granitoid rock bordering a discrete vein channel. The model suggests that the grey sericitic and sericitic with remnant biotite alteration envelopes at the porphyry copper deposit at Butte, Montana, can be formed by a reducing, low pH, and low salinity fluid under constant temperature and pressure conditions of approximately 400 °C and less than 100 MPa during a time span of approximately 100 years or less. Hydrothermal alteration has little effect on the porosity of the host rock (Butte Quartz Monzonite), and the diffusivity of the aqueous species also changes little. A sequence of mineral reaction fronts characterizes the alteration envelopes. The biotite dissolution front occurs closest to the vein channel and marks the transition from the grey sericitic to sericitic with remnant biotite envelope. The plagioclase dissolution front occurs farthest into the matrix and marks the edge of relatively fresh Butte Quartz Monzonite. From the properties of the quasi‐stationary state approximation ( Lichtner 1988 ; Lichtner 1991 ), it follows that once the sequence of reaction fronts is fully established, their relative locations remain constant and the widths of the reaction zones increase with the square root of time.  相似文献   
72.
One of the most important reference groups for Mycenaean pottery is the Mycenae/Berbati (MB). In several studies, a second group has been identified (MBKR). The chemical compositions were similar to MB, but with important differences in the Na, K and Rb contents. The present study suggests that these differences are due to selective alteration and contamination processes that are indirectly determined by the original firing temperature. Therefore, groups MB and MBKR should be considered as a single reference group.  相似文献   
73.
Majolica pottery is one of the most characteristic tableware produced during the Medieval and Renaissance periods. Majolica technology was introduced to the Iberian Peninsula by Islamic artisans during Medieval times, and its production and popularity rapidly spread throughout Spain and eventually to other locations in Europe and the Americas. The prestige and importance of Spanish majolica was very high. Consequently, this ware was imported profusely to the Americas during the Spanish Colonial period. Nowadays, Majolica pottery serves as an important horizon marker at Spanish colonial sites. A preliminary study of Spanish-produced majolica was conducted on a set of 246 samples from the 12 primary majolica production centers on the Iberian Peninsula. The samples were analyzed by neutron activation analysis (NAA), and the resulting data were interpreted using an array of multivariate statistical procedures. Our results show a clear discrimination between different production centers. In some cases, our data allow one to distinguish amongst shards coming from the same production location suggesting different workshops or group of workshops were responsible for production of this pre-industrial pottery.  相似文献   
74.
The European Union (EU) has been continuously rethinking its global position amidst emerging economic and geopolitical challenges and attempting to formulate strategies to increase its competitiveness. However, its long-standing policy implementation deficit is also recognized for its grand strategies, including the initially ambitious Lisbon Strategy. Is Europe 2020 set to fail as well? In this paper, we are arguing that strategic steering is essentially a discursive practice influenced by both semiotic and extra-semiotic factors. Hence, success or failure of a strategy essentially depends on ability to steer the discourse. Niklas Luhmann's social systems theory offers a theoretical framework against which limitations and potentials of strategic steering at the EU level can be analysed. While high levels of rationality and reflection capacities can improve strategic steering, it is limited by the increasing complexity. Recognizing limitations of direct and centralized interventions, we look for analytical and strategic solutions in sophisticated mechanisms of contextual steering: variation, selection and retention of strategic discourses. These mechanisms are integral to the “cultural political economy” approach. In the final part of the paper, we show how cultural political economy can explain the implementation shortcomings of the EU strategies.  相似文献   
75.
The classification of spatial planning styles in Europe has been successively reviewed a few times. Most recently, it has been done in the framework of the European Spatial Planning Observatories Network (ESPON) 2.3.2 project dealing with the territorial governance. Based on national overviews for 29 European countries, this project uses the classification of spatial planning systems in four styles: comprehensive-integrated, regional-economic, land-use and urbanism. This study did not take into account the spatial planning system in Serbia since it is neither in the European Union nor a member of the ESPON similar to Norway and Switzerland. This article uses the form of national overviews elaborated for the ESPON project and puts Serbia in a comparative spatial planning perspective, classifying it between the comprehensive-integrated and land-use planning styles.  相似文献   
76.
When in 1945 the Czechoslovak authorities confiscated the estate of the Princes von und zu Liechtenstein, the two countries became involved in a dispute which had not been resolved until recently, at least on a diplomatic level. For several decades, the 1948 Communist coup d'état in Czechoslovakia dashed the hopes of the Liechtenstein family for a restitution of their confiscated assets. However, officials responsible internally admitted that the property confiscation had been questionable in the case of the Liechtenstein family. The court had not confirmed the confiscation until after the Communist coup. However, the Liechtenstein family did not renounce their claims, and after the collapse of the Communist regime in 1989 they brought them up again.  相似文献   
77.
Shell middens distributed along the coastal areas of the Beagle Channel (Tierra del Fuego) testify the primary role of marine resources in the successful social dynamic of hunter–gatherer–fisher societies (HGF) in extreme high latitude environmental conditions. Intertidal and subtidal limpet species are frequently identified taxa of these archaeological deposits. We investigated whether shell δ18O of the limpet species Nacella deaurata is a valuable record of local sea surface temperature (SST) and ambient water δ18O (δ18Ow) fluctuations, and in turn can be used to estimate the season of its exploitation by Holocene HGF. Sequential shell δ18O of modern species track seasonal changes of SST and δ18Ow. The comparison of shell δ18O profiles of N. deaurata and Nacella magellanica (a coexisting species) suggests the occurrence of distinct growth rate and physiological adaptations between species. Shell δ18O of zooarchaeological specimens of N. deaurata from Lanashuaia II suggests that animals were exploited predominantly in winter and that experienced similar environmental conditions of present day at ∼1320 years BP. Results also indicate that N. deaurata is a valuable candidate for studying past seasonal changes in SST and δ18Ow in this southernmost part of South America.  相似文献   
78.
The ‘Castle Hill’ represents the core territory of Vilnius, around which gravitated urban development, eventually culminating in the foundation of the capital of Lithuania. However, we know very little about the earliest occupation on Castle Hill - how it developed over time, and what the activities were of the people that inhabited the site. While the study of plant remains can provide a crucial insight into human staple foods, agricultural activities and the palaeoenvironment, previous attempts of archaeobotanical investigations of such an important cultural heritage site was cut short due to the outbreak of World War II. Here is presented the first archaeobotanical analyses from the territory of Castle Hill together with new radiocarbon dates stretching from the 8th century BC until the 14th century AD. The primary archaeobotanical analyses in combination with published datasets from adjacent regions around Castle Hill show that the diversification of crops and the introduction of various crop rotation practises during the 8-13th centuries AD. Here, for the first time, attention is drawn to the agricultural strategies in medieval Vilnius that likely played a pivotal role in the formation and development of the city.  相似文献   
79.
This paper investigates the social structure of an Early Bronze Age society whose members were buried at the necropolis of Mokrin (Serbia, Southeastern Europe), by comparative analysis of musculo-skeletal markers (MSM) of activity and social status as induced on the basis of grave contents. The main objective of the analysis is to determine whether quantitative and qualitative differences in activity are related to social status. Besides using an overall measure of activity, we attempted to isolate different qualitative aspects (facets) of activity through factor analysis of MSM scores. No correlation between social status and overall labor intensity was found. However, there are clues that social status and a single facet of activity are related. Positive correlation between vertical status and the intensity of use of upper arm and shoulder muscles was found among male individuals, while negative correlation between the aforementioned variables was found among the females. The general conclusion based on the results of this study is that there is no simple correlation between the overall labor intensity and social status.  相似文献   
80.
Unlike journalists, anthropologists will tend to mostly anonymize the places they visit. However, as van der Geest has pointed out in these pages before, anonymity is not always what the people we research want from us. In this narrative, A.F. Robertson and Laura Cardús i Font show how our writing can become an asset to the communities we study, who, like us, are seeking to confirm their identities and improve their reputation in the overall scheme of things. In this narrative, the authors dwell on the nature of writing for both academic and vernacular audiences.  相似文献   
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