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Numerical modeling has emerged over the last several decades as a widely accepted tool for investigations in environmental sciences. In estuarine research, hydrodynamic and ecological models have moved along parallel tracks with regard to complexity, refinement, computational power, and incorporation of uncertainty. Coupled hydrodynamic-ecological models have been used to assess ecosystem processes and interactions, simulate future scenarios, and evaluate remedial actions in response to eutrophication, habitat loss, and freshwater diversion. The need to couple hydrodynamic and ecological models to address research and management questions is clear because dynamic feedbacks between biotic and physical processes are critical interactions within ecosystems. In this review, we present historical and modern perspectives on estuarine hydrodynamic and ecological modeling, consider model limitations, and address aspects of model linkage, skill assessment, and complexity. We discuss the balance between spatial and temporal resolution and present examples using different spatiotemporal scales. Finally, we recommend future lines of inquiry, approaches to balance complexity and uncertainty, and model transparency and utility. It is idealistic to think we can pursue a “theory of everything” for estuarine models, but recent advances suggest that models for both scientific investigations and management applications will continue to improve in terms of realism, precision, and accuracy.  相似文献   
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Central Iberian Variscan granite batholiths and anatectic complexes are punctuated by coeval stocks of hydrous, high-K calc-alkaline, ultrabasic to intermediate rock series. Despite their overall calc-alkaline affinity, the mafic–ultramafic members contain high-Ti amphibole oikocrysts rimmed by lower-Ti amphibole ± cummingtonite and high-Ti amphibole replacing early phlogopite. To understand the factors controlling the saturation of high-Ti amphibole in the parental magmas, clinopyroxene-melt, phlogopite-melt and amphibole-melt relationships are reviewed. This analysis reveals that for melts with intermediate compositions, the affinity of TiO2 for amphibole rises in alkalic magmas. Accordingly, mildly alkalic trachytoid to subalkaline medium- to high-K andesite and dacite compositions are estimated for interstitial high-Ti amphibole-saturated melts. Amphibole Ce/Pb ratios reveal a mantle–crust hybrid nature for interstitial melts with subalkaline trachytoid compositions. The hydrous character of the Variscan basic magmas favoured an overall magmatic evolutionary trend with a low rate of variation of Na2O with respect to silica during amphibole crystallization. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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International Journal of Earth Sciences - Graphite-rich metamorphic limestones included within low-grade black schists of the lowest Nevado-Filábride tectonic unit in the Sierra de Baza...  相似文献   
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A regional geologic study of Arabia Terra, a densely cratered area of Mars northern hemisphere, has revealed the individuality of this province. This is best expressed by an equatorial belt with a crater age distinctly younger as compared to the northern part of Arabia Terra and to Noachis Terra to the south. We interpret this as an incipient back-arc system provoked by the subduction of Mars lowlands under Arabia Terra during Noachian times. The regional fracture patterns are also best explained in this manner, making it unnecessary to appeal to a rotational instability of the planet, which is not supported by the palaeoclimatic indicators in the area. This model could be the first regional-scale confirmation of Sleep's (1994) hypothesis of a limited plate consumption as an explanation of the martian dichotomy. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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Geophysical methods have been used experimentally during the last decade, a period of strong development, being adopted as complementary techniques for characterizing and monitoring hydrocarbon and gas reservoirs. In this study, we evaluated the ability of the controlled source electromagnetic (CSEM) method to monitor the storage of CO2 at the Research Laboratory on Geological Storage of CO2 at Hontomín (Burgos, Spain). Two aspects of the CSEM monitoring were examined considering the geoelectrical structure at the site, the technological constraints and the noise conditions of the Hontomín area. Borehole-to-surface simulations were performed to evaluate the detectability of the resistivity changes in the reservoir and the capacity to determine the location of the CO2 plume. The synthetic time-lapse study explores the possibilities of CSEM monitoring with a deep electric source. Three depths of the source are analyzed: above the plume, inside the plume, and beneath the stored CO2. In terms of the Hontomín storage site, the study confirmed that a deep electric source located beneath the injection depth can provide valuable information on the behavior of the stored CO2.  相似文献   
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