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81.
Hydraulic and hydrochemical properties of deep sedimentary reservoirs of the Upper Rhine Graben,Europe 下载免费PDF全文
Hydraulic and hydrochemical data from several hundred wells mostly drilled by the oil and gas industry within the four deep carbonate and siliciclastic reservoirs of the Upper Rhine Graben area in France and Germany have been compiled, examined, validated and analysed with the aim to characterize fluids and reservoir properties. Due to enhanced temperatures in the subsurface of the Upper Rhine Graben, this study on hydraulic and hydrochemical properties has been motivated by an increasing interest in deep hydrogeothermal energy projects in the Rhine rift valley. The four examined geothermal reservoir formations are characterized by high hydraulic conductivity reflecting the active tectonic setting of the rift valley and its fractured and karstified reservoirs. The hydraulic conductivity decreases only marginally with depth in each of the reservoirs, because the Upper Rhine Graben is a young tectonically active structure. The generally high hydraulic conductivity of the reservoir rocks permits cross‐formation advective flow of thermal water. Water composition data reflect the origin and hydrochemical evolution of deep water. Shallow water to 500 m depth is, in general, weakly mineralized. The chemical signature of the water is controlled by fluid–rock geochemical interactions. With increasing depth, the total of dissolved solids (TDS) increases. In all reservoirs, the fluids evolve to a NaCl‐dominated brine. The high salinity of the reservoirs is partly derived from dissolution of halite in evaporitic Triassic and Cenozoic formations, and partly from the fluids residing in the crystalline basement. Water of all four reservoirs is saturated with respect to calcite and other minerals including quartz and barite. 相似文献
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Late Bronze Age Copper Smelting Slags from Luserna (Trentino,Italy): Interpretation of the Metallurgical Process 下载免费PDF全文
In the Late Bronze Age, the extractive metallurgy of copper in north‐eastern Italy achieved a peak of technological efficiency and mass production, as evidenced by the substantial number of metallurgical sites and the large volume of slags resulting from smelting activities. In order to define the technological features of the Late Bronze Age metallurgical process, more than 20 slags from the smelting site of Luserna (Trentino, Italy) were fully analysed by means of optical microscopy, X‐ray powder diffraction, X‐ray fluorescence spectrometry and scanning electron microscopy. Three different slag types were identified based on mineralogical and chemico‐physical parameters, each being interpreted as the product of distinct metallurgical steps. A Cu‐smelting model is proposed accordingly. 相似文献
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The paper investigates the patterns of technology and knowledge of the regions. The first aim of the paper is to determine cluster templates at the national level. The second aim of the paper is to investigate the technology and knowledge composition of the regional highpoint clusters. The paper identifies patterns of industrial linkages to define cluster templates and regional highpoints. The second part uncovers regional distributions of technology and knowledge. The data comes from Turkey’s 2012 input–output table. The location quotients use industrial employment statistics from the Turkish Statistical Institute. The technological and knowledge intensity classification follows Eurostat. The findings reveal 10 cluster templates in Turkey. Spatial distribution of the highpoint clusters reveals that most regions contain highpoint clusters with low technology and low knowledge-intensive sectors. The results reveal that highpoint clusters in Turkey’s regions contain industries whose technologies do not demand high skills, knowledge and sophistication. Limited existence of high-tech industries and low knowledge intensity in Turkey’s industry composition is a limiting factor for transition to high value-added manufacturing. Special emphasis should be directed towards constructing regional advantage, given the current levels of technology and knowledge intensity. 相似文献
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A. Gutirrez Garcia‐M. M. C. Savin N. Cantin S. Boudoumi P. Lapuente R. Chapoulie I. Pianet 《Archaeometry》2019,61(4):795-808
Identifying the origin of marble used in antiquity brings back to light details of the economic, social and political organization of classical societies, and characterizing in depth the chemistry of marble is key to discovering its provenance. Beyond X‐ray diffraction, which could reveal the presence of discriminant secondary crystalline phases and the quantification of accessory minerals combined with a multivariate analysis approach, solid‐state nuclear magnetic resonance (NMR) enables one to recognize the local structure arrangement of both crystalline and amorphous materials by looking at one or more selected atoms. In present paper targets the 13C nuclide, and thus the major component of marble, calcium carbonate. Whatever their geological origin, marbles 13C‐NMR spectra present only one resonance corresponding to the carboxyl function whose intensity and line width vary from one marble to another. If the variation of the NMR signal intensity observed is the result of great T1 variations (from 220 to 5300 s) and is linked to iron content, the line width reflects defects in the calcite crystal in which calcium has been replaced by another element such as magnesium, aluminium or strontium. The specific profile of the NMR signal has been used successfully to help determine the origin of some archaeological items. 相似文献
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The paper presents a brief overview and history of archaeometric research using instrumental neutron activation analysis at the Faculty of Chemistry of the University of Sofia. The archaeometric projects are listed and some of the results obtained in the investigations of glass, pottery and metals are described. 相似文献