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41.
X-ray images of sediment core allow recognition of fine-scaled sedimentary structures which traditional epoxy casts or lacquer peels are unable to resolve. The X-ray imaging system SCOPIX has the additional advantage of acquiring high-resolution digital pictures suitable for further analysis by advanced image processing techniques. Because of the frequent presence of both physical and biogenic sedimentary structures in undisturbed sediment cores, two image analysis procedures have been established which simplify the information contained in the images (in term of structures and facies), and allow a quantitative characterization of the observed structures. This form of parametrization of the image structure constitutes an additional source of information for a better interpretation of the physical processes responsible for the generation of the sedimentary structures. 相似文献
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Abstract. Benthic metabolism and standing stocks were investigated in the deep Red Sea between 21o and 27o N, Activity was assessed by the determination of respiration rates with a shipboard method and by calculating oxygen consumption from the activity in the electron transport system. We attempted to compare results from different latitudes within the warm Red Sea and with data from cold Atlantic environments. Our investigations were part of an environmental risk assessment to evaluate future mining of metalliferous sediments from the Atlantis II Deep. 相似文献
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V. A. Dulov S. I. Klyushnikov V. N. Kudryavtsev O. V. Shulgin O. G. Shcherbak 《Physical Oceanography》1991,2(4):269-282
An overview of experiments is given on the observation of the dependence of the intensity of wind wave breaking on large-scale
currents' inhomogeneities and atmospheric boundary layer stratification. The data were interpreted using a model in which
the variance of the wind wave breaking intensity reflects fluctuations in the influx of energy to wind waves due to various
factors.
Translated by V. Puchkin. 相似文献
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48.
The problem of monitoring of the mesoscale variability of hydrophysical fields in the shelf zone is considered. The usefulness of the data available in regional information centres is discussed. The possibility of monitoring the dynamics of the oceanic fields in the tropical Atlantic encompassing separate observation sites is demonstrated using the oceanographic databank of the scientific research centre (CERESCOR) in Conakry-Rogbane as an example. The results of assimilation of the hydrophysical survey data derived on the shelf in a telescopic model of the region are given.Translated by Mikhail M. Trufanov. 相似文献
49.
Darío R. Minkoff Mauricio Escapa Flix E. Ferramola Silvio D. Maraschín Jorge O. Pierini Gerardo M.E. Perillo Claudio Delrieux 《Estuarine, Coastal and Shelf Science》2006,69(3-4):403
The Bahía Blanca Estuary (38° 50′ S, and 62° 30′ W) presents salt marshes where interactions between the local flora (Sarcocornia perennis) and fauna (Chasmagnathus granulatus) generate some kind of salt pans that alter the normal water circulation and condition its flow and course towards tidal creeks. The crab–vegetation dynamics in the salt marsh presents variations that cannot be quantified in a reasonable period of time. The interaction between S. perennis plant and C. granulatus crab is based on simple laws, but its result is a complex biological mechanism that causes an erosive process on the salt marsh and favors the formation of tidal creeks. To study it, a Cellular Automata model is proposed, based on the laws deduced from the observation of these phenomena in the field, and then verified with measurable data within macroscale time units. Therefore, the objective of this article is to model how the interaction between C. granulatus and S. perennis modifies the landscape of the salt marsh and influences the path of tidal creeks. The model copies the basic laws that rule the problem based on purely biological factors.The Cellular Automata model proved capable of reproducing the effects of the interaction between plants and crabs in the salt marsh. A study of the water drainage of the basins showed that this interaction does indeed modify the development of tidal creeks. Model dynamics would likewise follow different laws, which would provide a different formula for the probability of patch dilation. The patch shape can be obtained changing the pattern that dilates. 相似文献
50.
A minor generalization of the theory of random walk is used as a basis for a model of ocean current flow. The model is then applied in a computer simulation of drifter motion. The results of simulation indicate that the geometry of a coastline can have significant impact on the distribution of drifter landings. 相似文献