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141.
Natural Resources Research - In most NI-43-101 resource assessment reports the prediction of global in situ resources is performed by either inverse distance weighting, ordinary kriging (OK) or... 相似文献
142.
The 15-km-long Matane pockmark train belongs to a series of NNE-striking alignments of pockmarks mapped on the seafloor of the St. Lawrence Estuary. It includes 109 pockmarks that show a complete transition from well-defined, relatively deep (up to 8.6 m), crater-like depressions to subtle, partly buried morphological features, suggesting that pockmarks have formed at different periods along the whole alignment and that the location of fluid release has changed through time. On seismic profiles, pockmarks are characterized by vertical seismic chimneys that root in the (fractured?) hinge zone of an open anticline within the autochthonous Palaeozoic rocks of the St. Lawrence Platform. In absence of a geochemical characterization of expelled gas, the relationship between the Matane pockmark train and the anticline in a domain characterized by mature source rocks is the strongest evidence for the genetic link between pockmarks and the release of gas from an active hydrocarbon system or a reservoir located in the Palaeozoic succession. Figure
Alignment of the Matane pockmark train along a buried bedrock anticline of the Lower St. Lawrence Estuary 相似文献
143.
Bruno Lansard Christophe Rabouille Lionel Denis Christian Grenz 《Estuarine, Coastal and Shelf Science》2009,81(4):544-554
Biogeochemical processes in sediments under the influence of the Rhône River plume were studied using both in situ microelectrodes and ex situ sediment core incubations. Organic carbon (OC) and total nitrogen (TN) content as well as stable carbon isotopic composition of OC (δ13COC) were analysed in 19 surface sediments to determine the distribution and sources of organic matter in the Rhône delta system. Large spatial variations were observed in both the total O2 uptake (5.2 to 29.3 mmol m−2 d−1) and NH4+ release (−0.1 to −3.5 mmol m−2 d−1) rates at the sediment–water interface. The highest fluxes were measured near the Rhône River mouth where sedimentary OC and TN contents reached 1.81% and 0.23% respectively. Values of δ13COC ranged from −26.83‰ to −23.88‰ with a significant seawards enrichment tracing the dispersal of terrestrial organic matter on the continental shelf. The amount of terrestrial-derived OC reaches 85% in sediments close to the Rhône mouth decreasing down to 25% in continental shelf sediments. On the prodelta, high terrestrial OC accumulation rates support high oxygen uptake rates and thus indicating that a significant fraction of terrestrial OC is remineralized. A particulate organic carbon (POC) mass balance indicates that only 3% of the deposited POC is remineralized in prodelta sediments while 96% is recycled on the continental shelf. It was calculated that a large proportion of the Rhône POC input is either buried (52%) or remineralized (8%), mostly on the prodelta area. The remaining fraction (40%) is either mineralized in the water or exported outside the Rhône delta system in dissolved or particulate forms. 相似文献
144.
Biological diversity, or biodiversity, is high on the international agenda for nature conservation. Marine and coastal ecosystems account for an important share of the biological diversity on Earth. As a consequence many international conventions, European legislation and national laws refer to marine biodiversity. The protection of marine biodiversity is a complex legal issue as it requires consideration of geographic (between land and sea), political (between conservation and exploitation), and economic (between fisheries, tourism, intellectual property and many other sectors) factors. Like Matryoshka dolls, marine biodiversity is a heterogeneous notion difficult to address as one discrete area in the development of policy agendas or juridical frameworks. In the past decade, the EU has been very active in Promoting Integrated Coastal Zone Management and in developing a framework for an Integrated Maritime Policy. This article reviews the status of marine biodiversity in the policy and legal initiatives of the European Union, a challenging issue to both the objectives of conservation and to the concept of integration. 相似文献
145.
The semi-diurnal tides are amplified and distorted as they propagate into the Pertuis Breton, a semi-enclosed shallow basin in the north-eastern part of Bay of Biscay, in France. This paper investigates the influence of bottom friction on amplification and phase lag of the tidal constituent M2 and its overtide M4 in the Pertuis Breton. A fine resolution two-dimensional (2D) numerical model is implemented to simulate tidal propagation. The model solves the depth-averaged shallow-water equations on a finite element grid using the TELEMAC 2D software. A two-zone parameterisation of friction coefficient is introduced to evaluate the impact of smooth mud flats on the tidal asymmetry and amplification in the Pertuis. Fitting the model to observed amplitudes and phases of M2 and M4 evaluates the decrease of Chezy friction coefficient from the mud flats to the rest of the Pertuis as 100:60. This conclusion is supported by the direct estimation based on morphology and composition of sea bed in the Pertuis Breton. 相似文献
146.
We present a comparison between several methods used to reconstruct fluxes and vertical profiles of wind, temperature and
humidity from measurements at two levels in the atmospheric surface layer for different practical applications. An analytical
method and an iterative method are tested by evaluating the quality of estimations of surface fluxes from detailed field measurements
obtained during a campaign on the site of Lannemezan in the south-west of France. The iterative method yields better results,
but the analytical one can give results of the same level of accuracy provided that specific constants in its formulation
are modified. Then these techniques are applied to wind and temperature reconstruction for an experiment dedicated to wind
power estimates over flat terrain. If turbulent fluxes are not needed, a simple power law appears to be sufficient, as the
method based on Monin–Obukhov theory does not improve the accuracy of the vertical profile reconstruction. 相似文献
147.
Christelle Dère Isabelle Lamy Folkert van Oort Denis Baize Sophie Cornu 《Comptes Rendus Geoscience》2006,338(8):565-573
Raw wastewaters were massively spread on sandy luvisols near Paris from 1899 to 2002, leading to high trace metals (TM) pollution of soils. Mass balance calculations were performed on a soil profile to assess vertical migration of TM. The contamination was estimated by subtracting the natural pedo-geochemical background of the horizons. TM inputs were estimated using Cr as an invariant. It is shown that Pb and Cr remained in the surface horizon, while Ni, Cd, Cu and Zn migrated downward, being more or less trapped depending on the physicochemical properties of the horizons. To cite this article: C. Dère et al., C. R. Geoscience 338 (2006). 相似文献
148.
Recent Russian legislative and policy documentation concerning national progress towards sustainable development has suggested that the attainment of such a state would represent the first stage in the development of the noosphere as outlined by the Russian scientist Vladimir Ivanovich Vernadsky (1863-1945). This paper explores Vernadsky’s model of evolutionary change through a focus on his work on the biosphere and noosphere in an attempt to further understanding of the way in which Russia is approaching the concept of sustainable development in the contemporary period. It is argued that the official Russian interpretation of the noosphere idea tends to obscure the evolutionary and materialist foundations of Vernadsky’s biosphere-noosphere conceptualisation. At the same time, the concluding section of the paper suggests that the scope of Vernadsky’s work can be used to stimulate the search for a more coherent approach to work in areas of sustainable development and sustainability across the span of the social and physical sciences. 相似文献
149.
Pierre Nehlig Fawsia Asfirane Antonin Genna Catherine Guerrot Nadège Nicol Ignace Salpeteur Mohammed Shanti & Denis Thiéblemont 《地学学报》2001,13(5):347-353
A new aeromagnetic map together with new geological and geochronological data has led to a reinterpretation of the geological history of the Arabian Shield.
The magnetic anomalies outline an orogenic complex containing a network of mostly left-lateral strike-slip faults, including the Nabitah Belt and several peripheral mountain ranges. Oblique accretion resulted in obliteration of early volcanic-arc magnetic fabrics, which were almost completely replaced by a NW–SE magnetic fabric in the northern Shield; the southern Shield, however, reveals extensive E–W anomalies related to post-accretion magmatic intrusions. This complex web of orogenic zones is intimately associated with synchronous molasse basins that formed 680–610 Ma.
The distribution and chronology of orogenic zones, related to the closing of East and West Gondwana, brings into question several earlier assumptions, such as high continental growth rates, palaeogeodynamic reconstructions, the definitions of the Nabitah and Najd faults, and the significance of molasse basins. 相似文献
The magnetic anomalies outline an orogenic complex containing a network of mostly left-lateral strike-slip faults, including the Nabitah Belt and several peripheral mountain ranges. Oblique accretion resulted in obliteration of early volcanic-arc magnetic fabrics, which were almost completely replaced by a NW–SE magnetic fabric in the northern Shield; the southern Shield, however, reveals extensive E–W anomalies related to post-accretion magmatic intrusions. This complex web of orogenic zones is intimately associated with synchronous molasse basins that formed 680–610 Ma.
The distribution and chronology of orogenic zones, related to the closing of East and West Gondwana, brings into question several earlier assumptions, such as high continental growth rates, palaeogeodynamic reconstructions, the definitions of the Nabitah and Najd faults, and the significance of molasse basins. 相似文献
150.
An asymptotic representation is developed for high order unstable gravity modes in a star which are associated with a convective zone enclosed between two radiative layers. In the domain which contains both turning points of the differential equation, the solutions are represented by a single asymptotic expansion in terms of Weber functions. 相似文献