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911.
W. D’ALESSANDRO L. BRUSCA K. KYRIAKOPOULOS M. MARTELLI G. MICHAS G. PAPADAKIS F. SALERNO 《Geofluids》2011,11(1):97-107
Methane soil flux measurements have been made in 38 sites at the geothermal system of Sousaki (Greece) with the closed chamber method. Fluxes range from ?47.6 to 29 150 mg m?2 day?1, and the diffuse CH4 output of the system has been estimated at 19 t a?1. Contemporaneous CO2 flux measurements showed a moderate positive correlation between CO2 and CH4 fluxes. Comparison of the CO2/CH4 soil flux ratios with the CO2/CH4 ratio of the gases of the main gas manifestations provided evidence for methanotrophic activity within the soil. Laboratory CH4 consumption experiments confirmed the presence of methanotrophic microorganisms in soil samples collected at Sousaki. Consumption was generally in the range from ?4.9 to ?38.9 pmolCH4 h?1 g?1 but could sometimes reach extremely high values (?33 000 pmolCH4 h?1 g?1). These results are consistent with recent studies on other geothermal systems that revealed the existence of thermoacidophilic bacteria exerting methanotrophic activity in hot, acid soils, thereby reducing methane emissions to the atmosphere. 相似文献
912.
This study reconstructs the palaeohydrogeologic evolution of the shallow‐to‐moderate Mesozoic subsidence history for the Mecsekalja Zone (MZ), a narrow metamorphic belt in the eastern Mecsek Mountains, Hungary. Brittle deformation of the MZ produced a vein system with a cement history consisting of five sequential carbonate generations and one quartz phase. Vein textures suggest different fluid‐flow mechanisms for the parent fluids of subsequent cement generations. Combined microthermometric and stable‐isotope measurements permit reconstruction of the character of subsequent fluid generations with different flow types, as defined by vein textures, yielding new information regarding the hydraulic behaviour of a metamorphic crystalline complex. Textural observations and geochemical data suggest that fracture‐controlled flow pathways and externally derived fluids were typical of some flow events, while percolation through the rock matrix and the relationship to the Cretaceous volcanism and dyke emplacement were typical of others. The difference in the mode of calcite deposition from pervasive fluids (i.e. pervasive carbonatisation along grain boundaries versus deposition in antitaxial veins) between two calcite generations related to the volcanism inspired a stress‐dependent model of antitaxial vein growth. Textural and isotope variations in a vein generation produced by the same parent fluid indicate rock‐dependent hydraulic behaviour for different rock types, distinct action of the contemporaneous fracture systems and different extents of fluid–rock interaction. Cathodoluminescence microscopy and fluid‐inclusion microthermometry shed light on the possible role of hydraulic fracturing in the formation of massive calcite. The time of formation was estimated from the isotope composition of the oldest calcite generation and its presumptive relationship with the sedimentary sequences to the north, whereas microthermometry permitted conciliation of the reconstructed flow sequence with the Mesozoic subsidence history of the Mórágy Block (including the MZ). 相似文献
913.
F. BERNARDINI A. DE MIN D. EICHERT A. ALBERTI G. DEMARCHI A. VELUŠČEK C. TUNIZ E. MONTAGNARI KOKELJ 《Archaeometry》2011,53(2):261-284
The change of raw materials used to produce stone axes during the Neolithic to Copper Age transition in northeastern Italy, central and western Slovenia and northwestern Croatia (Caput Adriae) has been recently linked to the development of early European metallurgy. Serpentinite shaft‐hole axes occur commonly in the archaeological context of this region and their rounded irregular shape suggests that the raw material was mainly sourced from secondary deposits. The aim of the present study is to characterize with multiple analytical methods, including synchrotron radiation, the axes and locate the primary outcrop(s) of raw materials and related secondary exploitation areas. All the analysed artefacts are manufactured from peridotites and probably pyroxenites completely metamorphosed in greenschist facies and characterized by antigorite, diopside and magnetite, sometimes rimmed by penninite. Mineralogical and petrographic data exclude most Eastern Alps outcrops as possible raw material sources, thus limiting the research to the Hohe Tauern. Chemical data reveal a close homogeneity for the peridotite‐derived axes and therefore demonstrate a selection of the most suitable raw material for axe production. Provenance from Hohe Tauern and related secondary deposits of the Drava River hydrographical system agrees with previous studies, as this region is rich in copper ore deposits, which have been exploited since prehistory. 相似文献
914.
F. CARUSO M. L. SALADINO A. SPINELLA C. DI STEFANO P. TISSEYRE S. TUSA E. CAPONETTI 《Archaeometry》2011,53(3):547-562
The archaeological discovery of the Acqualadrone rostrum (an offensive naval weapon mounted on the prow at the waterline), off the Italian coast near Messina in 2008, has led to the need for scientific research in order to plan the conservation treatment of this artefact. The discovery is exceptional because of the presence of a wooden section from the original ship. This paper describes the physico‐chemical characterization of a metallic and two wooden samples by inductively coupled plasma – optical emission spectroscopy, inductively coupled plasma – mass spectrometry, Fourier transform infrared spectroscopy, 13C {1H} cross‐polarization magic angle spinning NMR spectroscopy, energy‐dispersive X‐ray spectroscopy, gas chromatography – mass spectrometry and X‐ray diffraction. The results reveal the use of leaded bronze (Cu, 70%; Pb, 20%; Sn, 10%) in the manufacturing process of the alloy and the use of lead whose isotopic composition is referable to either Spanish or Cypriot mines. The analysis of the results relating to the wooden samples indicates their different state of preservation and, at least in some places, the spreading of caulking on the wood, probably using a vegetable resin. 相似文献
915.
M. SECCO L. MARITAN C. MAZZOLI G. I. LAMPRONTI F. ZORZI L. NODARI U. RUSSO S. P. MATTIOLI 《Archaeometry》2011,53(4):809-829
Post‐depositional processes in pottery can give rise to chemical and mineralogical alterations, the extent of which is closely related not only to the microstructure and composition of the potsherds, but also to the chemical–physical conditions of the burial environment. The present paper describes the characterization of post‐depositional alterations and identification of processes involving pottery buried in lagoon‐like environments. A set of various types of Roman transport amphorae and African Red Slip ware (ARS), collected from two archaeological sites characterized by a lagoon‐like depositional environment and showing evident changes in the original colours, was analysed by a combination of microstructural, mineralogical and microchemical approaches. The formation of pyrite after hematite, jarosite after pyrite and microstructural substitution features are interpreted here in terms of the chemico‐physical conditions of the burial environment and their evolution in time. 相似文献
916.
917.
918.
Eugenio F. Biagini 《History of European Ideas》2011,37(2):211-217
This article explores the link between religion and politics, religious liberty and the rights of religious minorities, by focusing on the constitutions which Italian states adopted and discarded from 1796 to 1849. It concerns questions about the ‘national character’ and the rights and duties of the citizen, and argues that - far from being ‘an outlet’ for material discontent - questions of religious identity and pluralism were integral to the Risorgimento definition of liberty. In this context, the author explores also the Mazzinian vision of a democratic republic inspired by an acephalous and non-hierarchical civil religion, similar to the Unitarian Transcendentalism practiced by some of his New York admirers - a far cry from the ‘religions of politics’ inspired by Saint Simon and Auguste Comte. 相似文献
919.
Jon M. Erlandson Todd J. Braje Torben C. Rick Nicholas P. Jew Douglas J. Kennett Nicole Dwyer Amira F. Ainis René L. Vellanoweth Jack Watts 《Journal of archaeological science》2011
To investigate potential human impacts on California Channel Island shellfish stocks over the past 10,000 years, we measured 1718 owl limpet shells from 19 archaeological components on San Miguel Island. Inhabiting the middle intertidal zone of Pacific Coast rocky shores, owl limpets are slow-growing mollusks that can live for 30 years and reach lengths of over 100 mm. Recent ecological studies indicate that owl limpets are highly susceptible to heavy human predation, which results in reduced mean shell sizes among Lottia populations along the coasts of Alta and Baja California. On San Miguel Island, we identified a significant trans-Holocene reduction in mean owl limpet size, beginning more than 6500 years ago and accelerating at least 4400 years ago. Fluctuations in limpet size show no clear correlation with changes in sea surface temperature and marine productivity, suggesting that increased predation by growing human populations was primarily responsible for the reduction in Lottia size over time. Our results provide further evidence that prehistoric peoples significantly influenced nearshore fisheries long before the development of the commercial and industrialized fisheries of historic times. 相似文献
920.
Sandström G 《Scandinavian journal of history》2011,36(1):65-90
This study examines how the divorce rates in Sweden have varied over time and across different geographical areas during the period 1911-1974, and how these variations can be connected to the political, socio-economic and cultural development in Sweden. The analysis provides empirical support for the hypothesis that increased divorce rates have been the result of changes in the structural conditions that determine the degree of economic interdependence between spouses. There is a strong connection between the degree of urbanization and the divorce rate on a regional level for the entire research period. The statistical analysis of the regional data indicates that these patterns are connected to the more diversified economy that has developed in urban settings, in the form of a more qualified labour market and higher wages for females. These characteristics resulted in a faster and more pronounced reduction of economic interdependence between spouses, which made divorce more attainable in these areas as compared with rural settings. 相似文献