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431.
The North Indian Ocean exhibits profound impact of variation in lower tropospheric winds. In the present study climatological monthly winds are used to force a nonlinear reduced gravity model of the North Indian Ocean to simulate climatological surface circulation and sea level anomaly for all 12 months of the year. The sea level anomalies agree reasonably well with satellite altimeter derived sea level anomalies. The model successfully simulates the varying eddy structure and current pattern of the North Indian Ocean. Finally, the kinetic energy variation in the North Indian Ocean with special reference to equatorial region and the boundaries is analyzed in detail. 相似文献
432.
Bianchi Type I string dust cosmological models in presence and absence of magnetic field following the techniques used by
Letelier and Stachel, are investigated. To get the deterministic solution, we have assumed that σ
11 is proportional to the expansion (θ) where σ
11 is the eigen value of shear tensor (σ
i
j
) and which leads to A=N(BC)−n
, n>0 where A,B,C are metric potentials and
, N and ℓ are constants. The behaviour of the models in presence and absence of magnetic field are discussed. The other physical and
geometrical aspects of the model are also discussed. 相似文献
433.
Helga de Wall Stefan Schöbel Manoj K. Pandit Kamal K. Sharma J. Just 《Journal of the Geological Society of India》2010,75(1):239-253
The Mirpur granite body represents a relatively small (10 km2) pluton intruded along the northern margin of the adjacent Mt. Abu batholith (∼125 km2) in NW India. It is a visibly undeformed alkali feldspar rich pink granite; in contrast, the Mt. Abu is a composite granitoid
body and variably deformed. Both are intruded by rhyolitic dykes and the terminal magmatic events in both the cases are mafic
dykes. The AMS (Anisotropy of Magnetic Susceptibility) data identify the Mt. Abu with SE-dipping foliations and subvertical
lineations as a single structural domain while the Mirpur granite body shows two domains characterized by predominantly E
— W trend of magnetic foliation in the eastern part (domain I) and N — S orientations in the western part (domain II). The
domain I shows magmatic fabrics, typical for the peraluminous granites of Malani Igneous Suite (MIS). Change in fabric orientation
in the domain II has resulted from cataclasis wherein the samples show destruction of the original E — W fabric and complete
transposition by N — S trends. The foliations in the Mt. Abu granites have been related to SE orientation of maximum horizontal
stress. The same maximum stress direction can be inferred from dyke orientation in the Mirpur granite, which is interpreted
as continuation of the tectonic imprint in this region during emplacement of both the granites. Age of the cataclastic overprint
with a predominant N — S orientation is not yet constrained but corresponds with the trend of the nearby Sindreth basin within
the Malani Igneous Suite. The Neoproterozoic tectonic scenario for the region has been interpreted in terms of an ongoing
crustal convergence and granitic magma emplacement against the back stop offered by the rigid Delhi Fold Belt. 相似文献
434.
Drinking and irrigational feasibility of groundwater,GIS spatial mapping in upper Thirumanimuthar sub-basin,Cauvery River,Tamil Nadu 总被引:1,自引:0,他引:1
M. Suresh B. Gurugnanam S. Vasudevan K. Dharanirajan N. Jawahar Raj 《Journal of the Geological Society of India》2010,75(3):518-526
In the present study, the chemical characteristics of groundwater with respect to drinking and Irrigation water quality in
upper Thirumanimuthar sub-basin, Cauvery River, have been studied. 51 groundwater samples were collected and analysed for
pH, conductance, total dissolved solids, total hardness, calcium, magnesium, carbonate, bicarbonate, total alkalinity, chloride,
sodium, potassium, sulphate etc. The values analyzed were evaluated in detail and compared with WHO water quality standards.
It is observed that, for most of the groundwater quality parameters, the values are not potable for drinking and irrigational
use. To understand the spatial distribution of unsuitable zones, ArcGIS was employed. Attributes were linked and spatial interpolation
mapping was done. Inverse distance weighted interpolation technique was followed for raster and vector mapping. Finally the
overlay analyses were also carried out to locate the worst quality zone. 相似文献
435.
Numerical model and flume experiments of single- and two-layered hillslope flow related to slope failure 总被引:1,自引:0,他引:1
A hillslope flow model is developed considering 3D saturated and unsaturated flow of water during rainfall events. A finite difference-based numerical model of hillslope flow processes is developed. Four different experiments are done to see the effects of a single- and double-layered soil in pore-water pressure dynamics and slope failure. Results from the numerical model are verified with experimental results. The numerical and experimental values of the pore-water pressure and moisture contents are in good agreement. The results show that the hillslope heterogeneity caused by multiple layers of soil has greater influence on hillslope pore-pressure dynamics and slope failure patterns. The depth of slope failure shows high dependency on layering characteristics of the soil slope and pattern of rainfall. The proposed model provides a perspective on failure mechanism of a single- or double-layered slope under rainfall infiltration. 相似文献
436.
437.
In this paper, we developed statistical method for distance determination of a stellar group. The method depends on the assumption that, the stars scatter around a mean magnitude in a Gaussian distribution. The mean apparent magnitude of the stars is then expressed in terms of the frequency function of the apparent magnitudes, so as to correct for observational incompleteness at the faint end. The problem reduces to the solution of a highly transcendental equation for a given apparent magnitude parameter α. Computational algorithm of the method is illustrated and the numerical solutions of the basic equation are given for some values of α . 相似文献