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231.
Sergee A. Shapiro Pascal Audigane & Jean-Jacques Royer 《Geophysical Journal International》1999,137(1):207-213
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233.
From 1984 to 1993, the Georgia Geologic Survey (GGS) participated in the Minerals Management Service-funded Continental Margins Program. Geological and geophysical data acquisition focused on offshore stratigraphic framework stud ies, phosphate-bearing Miocene-age strata, distribution of heavy minerals, nearsurface alternative sources of groundwater, and development of a PC-based Coastal Geographic Information System (GIS). Seven GGS publications document results of those investigations. In addition to those publications, direct benefits of the GGS's participation include an impetus to the GGS's investigations of economic minerals on the Georgia coast, establishment of a GIS that includes computer hardware and software, and seeds for additional investigations through the information and training acquired as a result of the Continental Margins Program. These additional investigations are quite varied in scope, and many were made possible because of GIS expertise gained as a result of the Continental Margins Program. Future investigations will also reap the benefits of the Continental Margins Program. 相似文献
234.
R. McDermid E. Emsellem M. Cappellari H. Kuntschner R. Bacon M. Bureau Y. Copin R. L. Davies J. Falcn‐Barroso P. Ferruit D. Krajnovi R.F. Peletier K. Shapiro F. Wernli P.T. de Zeeuw 《Astronomische Nachrichten》2004,325(2):100-103
We present a summary of high‐spatial resolution follow‐up observations of the elliptical (E) and lenticular (S0) galaxies in the SAURON survey using the OASIS integral field spectrograph. The OASIS observations explore the central 8″ × 10″ regions of these galaxies using a spatial sampling four times higher than SAURON, often revealing previously undiscovered features. Around 75% (31/48) of the SAURON E/S0s with central velocity dispersion ≳ 120 km s−1 were observed with OASIS, covering well the original SAURON representative sample.We present here an overview of this follow‐up survey, and some preliminary results on individual objects, including a previously unreported counter‐rotating core in NGC4382; the decoupled stellar and gas velocity fields of NGC2768; and the strong age gradient towards the centre of NGC3489. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
235.
A multi-envelope generalised coordinate system for numerical ocean modelling is introduced. In this system, computational levels are curved and adjusted to multiple ‘virtual bottoms’ (aka envelopes) rather than following geopotential levels or the actual bathymetry. This allows defining computational levels which are optimised to best represent different physical processes in different sub-domains of the model. In particular, we show how it can be used to improve the representation of tracer advection in the ocean interior. The new vertical system is compared with a widely used z-partial step scheme. The modelling skill of the models is assessed by comparison with the analytical solutions or results produced by a model with a very high-resolution z-level grid. Three idealised process-oriented numerical experiments are carried out. Experiments show that numerical errors produced by the new scheme are much smaller than those produced by the standard z-partial step scheme at a comparable vertical resolution. In particular, the new scheme shows superiority in simulating the formation of a cold intermediate layer in the ocean interior and in representing dense water cascading down a steep topography. 相似文献
236.
Bioremediation in Fractured Rock: 1. Modeling to Inform Design,Monitoring, and Expectations 下载免费PDF全文
Claire R. Tiedeman Allen M. Shapiro Paul A. Hsieh Thomas E. Imbrigiotta Daniel J. Goode Pierre J. Lacombe Mary F. DeFlaun Scott R. Drew Carole D. Johnson John H. Williams Gary P. Curtis 《Ground water》2018,56(2):300-316
Field characterization of a trichloroethene (TCE) source area in fractured mudstones produced a detailed understanding of the geology, contaminant distribution in fractures and the rock matrix, and hydraulic and transport properties. Groundwater flow and chemical transport modeling that synthesized the field characterization information proved critical for designing bioremediation of the source area. The planned bioremediation involved injecting emulsified vegetable oil and bacteria to enhance the naturally occurring biodegradation of TCE. The flow and transport modeling showed that injection will spread amendments widely over a zone of lower‐permeability fractures, with long residence times expected because of small velocities after injection and sorption of emulsified vegetable oil onto solids. Amendments transported out of this zone will be diluted by groundwater flux from other areas, limiting bioremediation effectiveness downgradient. At nearby pumping wells, further dilution is expected to make bioremediation effects undetectable in the pumped water. The results emphasize that in fracture‐dominated flow regimes, the extent of injected amendments cannot be conceptualized using simple homogeneous models of groundwater flow commonly adopted to design injections in unconsolidated porous media (e.g., radial diverging or dipole flow regimes). Instead, it is important to synthesize site characterization information using a groundwater flow model that includes discrete features representing high‐ and low‐permeability fractures. This type of model accounts for the highly heterogeneous hydraulic conductivity and groundwater fluxes in fractured‐rock aquifers, and facilitates designing injection strategies that target specific volumes of the aquifer and maximize the distribution of amendments over these volumes. 相似文献
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238.
The paper describes the thermohaline structure of the Izmir waters obtained from three CTD-surveys carried out in different
seasons of 1994. Also, the mechanisms responsible for the formation of the regional peculiarities and the variability of the
temperature/salinity field and examined. The results of diagnosis and adaptation computations of the three-dimensional water
circulation are analysed, applying a numerical model and CTD-data.
Translated by Vladimir A. Puchkin. 相似文献
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240.
We discuss the results of numerical experiments aimed at the investigation of the process of formation of the three-dimensional
structure of the zones of upwelling on the northwest shelf of the Black Sea depending on the direction of the wind. We perform
the detailed analysis of three zones (I, II, and III) with fairly well pronounced inhomogeneities of the bottom topography.
Zone I is located in the north part of the shelf and, in this region, we observe a narrow depression to the southwest of the
Tendrovskaya Spit. In zone II located in the near-Danube zone, we observe a height reaching the sea surface (Zmeinyi Island).
Zone III is located in the east part of the shelf and corresponds to a sharp drop of depths with specific curvature of the
coastal line of the Kalamitskii Bay and Gerakleiskii Peninsula. The performed analysis enables us to conclude that, in the
vicinity of the local features of the bottom topography and coastal line (such as underwater heights, depressions, and capes),
we observe the appearance of the zones of upwelling of waters, especially pronounced in the deep-water layers of the sea.
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Translated from Morskoi Gidrofizicheskii Zhurnal, No. 3, pp. 68–80, May–June, 2008. 相似文献