排序方式: 共有66条查询结果,搜索用时 31 毫秒
51.
52.
Morphostructure of the Egyptian Continental Margin: Insights from Swath Bathymetry Surveys 总被引:1,自引:0,他引:1
Jean Mascle Olivier Sardou Lies Loncke Sébastien Migeon Laurent Caméra Virginie Gaullier 《Marine Geophysical Researches》2006,27(1):49-59
In the Eastern Mediterranean, offshore Egypt, the Nile continental margin is characterized by a large deep water turbiditic
system known as the Nile Deep Sea Fan. This post-Miocene terrigenous construction covers an approximately 10 km-thick sedimentary
pile, including 1–3 km of Messinian salt layers. Systematically collected swath bathymetric data proved to be the most powerful
tool to discover, describe and study many sea floor features of this sedimentary construction which reflects competition between
active tectonic, sedimentary, and geochemical processes. Gravity tectonics, triggered by underlying mobile salt layers, construction
of channel-levee systems, the passage of turbidite flows, sedimentary slope failures at various scales, massive mud expulsions
and fluid seepages are all interfering to shape the Nile Deep Sea Fan seabed. 相似文献
53.
Although high seas resources are being exploited, reciprocal legal obligations to protect its environment have not been met. Marine spatial planning (MSP) is clearly a practical way forward, particularly for the high seas, where non-spatial monitoring is difficult, and where data gaps obstruct conventional management approaches. To ensure the effective application of MSP in the high seas, however, some institutional reforms are necessary. This paper outlines the main hurdles, summarizes existing high seas spatial protections, presents an example of a high seas marine protected area that resulted through MSP, identifies three institutional priorities, and suggests three immediate steps. 相似文献
54.
Virginie Mamadouh 《GeoJournal》1999,48(2):133-144
The linguistic diversity in the European Union is generally viewed as an essential component of the European identity, but the linguistic regime of the EU institutions (with eleven official and working languages) is not undisputed. In addition, the upcoming enlargements will complicate greatly the continuation of the present practices as new Member States bring new official languages. As a result, the debate about possible reforms is likely to be boosted by the necessity to prepare EU institutions for further enlargment. The present regime of institutional multilingualism is criticised from different angles, resulting in three options for the future. In this paper the linguistic regime of EU institutions is discussed in relation to general ideas about the nature of this supranational political system. Supranationalism is treated here as a program to supersede nationalism. Three variants are distinguished: pacified nationalism, neo-nationalism and post-nationalism. The paper examines how these different visions of Europe shed different lights on the issue of multilingualism (in terms of communication, identity and power) and its institutionalisation in the linguistic regime of the core instituions of the European Union. Although the three models are compatible with several arrangements, they support or oppose them for different reasons. Besides, they differ regarding the significance of the linguistic regime of the EU institutions for the whole polity and their ability to steer linguistic practices. 相似文献
55.
Grid-group cultural theory: an introduction 总被引:2,自引:0,他引:2
Virginie Mamadouh 《GeoJournal》1999,47(3):395-409
This article offers an introduction to grid-group cultural theory (also known as grid-group analysis, Cultural Theory or theory
of socio-cultural viability), an approach that has been developed over the past thirty years in the work of the British anthropologists
Mary Douglas and Michael Thompson, the American political scientist Aaron Wildavsky, and many others. This assessment begins
with a presentation of the main claims of the theory, distinguishing two characteristic breads of grid-group cultural theory,
in the one it is conceived as a heuristic device, in the other it is seen as a full explanatory theory. This brief is followed
by a discussion of the typology generated by the theory. This includes a presentation of the two dimensions of sociality it
posits, the cultural map they produce, as well as the four (or five) cultural types derived from them and their designations.
The article proceeds with a discussion of key issues including the incorporation of other typologies (such as the one developed
to analyse myths of nature), the relations between cultures or rationalities and several methodological issues. Finally the
article introduces the contributions to this special issue of the GeoJournal.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
56.
Matthieu Waeles Virginie Tanguy Gaëtane Lespes Ricardo D. Riso 《Estuarine, Coastal and Shelf Science》2008,80(4):538-544
The frontal cascade ultrafiltration (UF) technique in conjunction with stripping chronopotentiometry (SCP) has been evaluated for determining the colloidal distribution of Cu, Pb and Cd in estuarine waters. Metallic concentrations in seven size fractions (0.45 μm–0.22 μm; 0.22 μm–300 kDa; 300–50 kDa; 50–30 kDa; 30–10 kDa; 10–5 kDa; <5 kDa) were determined with the aim to investigate their changes along the salinity gradient of the Penzé system (NW France). These data, completed by analysis of the total dissolved metals at 10 stations over the whole freshwater–seawater mixing zone, provided some insights in the removal and addition processes that affect Cu, Pb and Cd in estuaries. 相似文献
57.
Sandra Barbouteau Patrick Rasolofosaon Noalwenn Dubos‐Sallée Virginie Vassil Jean‐François Nauroy 《Geophysical Prospecting》2017,65(1):240-250
An alternative laboratory technique to measure the elastic constants of solid samples, based on the analysis of the cross‐correlation spectra of the vibratory response of randomly excited short solid cylinders, has been recently proposed. The aim of this paper is to check the ability of the technique called passive ultrasonic interferometry to monitor fluid substitution in different rock samples. Velocity variations due to fluid substitution are easily measured if the wave attenuation in the fluid‐saturated rock is not too large (typically in rocks with few cracks or microfractures). The experimental results are in agreement with the predictions of Biot–Gassmann poroelastic theory. The effect of substituting water with a stiffer saturating fluid, such as ethylene glycol, is to increase the overall bulk modulus of the rock, without any substantial effect on shear modulus. Furthermore, the experimental results compare well with those obtained independently with conventional pulse‐transmission technique using ultrasonic transducers. However, the measured pulse‐transmission bulk moduli are slightly larger than the corresponding measured ultrasonic interferometry moduli, with the deviation increasing with increasing fluid viscosity. This can be explained by dispersion due to wave‐induced flow of the viscous fluid since pulse‐transmission experiments involve higher frequencies than ultrasonic interferometry experiments. 相似文献
58.
Ana Colaço Catarina Prieto Ana Martins Miguel Figueiredo Virginie Lafon Margarida Monteiro Narcisa M. Bandarra 《Marine environmental research》2009,67(3):146-152
Specimens of the hydrothermal mussel Bathymodiolus azoricus collected in Menez Gwen hydrothermal vent field (NE Atlantic) during 2002–2003 were examined for feeding patterns variations through three seasons. The fatty acid profile and lipid classes of the mussels were studied, together with the MODIS/AQUA-derived near-surface chlorophyll a to test the hypothesis that surface productivity might be related to the feeding patterns of this species. The lipid levels showed pronounced seasonal fluctuations with the highest values occurring in January and August. Seasonal variations in lipid classes and fatty acid composition of neutral and polar lipids in the mussels are presented. Differences in the fatty acid profile of lipid classes in different seasons suggest that the higher energy requirements in summer and winter were supplied by bacterial biomarkers ω7 MUFA (monounsaturated fatty acids), whereas ω6 PUFA (polyunsaturated fatty acids) and NMI (non-methylene-interrupted) fatty acids predominated during the spring. The MODIS/AQUA data show marked seasonal variability and an anomalous peak during January of 2003, although this cannot be directly linked to lipid composition variation. 相似文献
59.
This article offers an analysis of the emerging scalar configuration of the governance of the European Union. It discusses how European integration stands for a move from a collection of territorially homogenous systems of rule towards a new assemblage of territories, authorities and rights. The paper first questions the stretchy territoriality of the seemingly obvious European level. Second it analyses the sectoral differences in the evolution of the width and the depth of integration, measured as the transfer of competencies to the EU level between the Rome Treaty (1958) and the Lisbon Treaty (200y). Third it turns to the day-to-day decision-making to assess the relations between players in EU governance and finally it looks more closely at the administrative wheels of the EU machinery. 相似文献
60.