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61.
The vicinity of the India-Burma border region is among a few intracontinental regions in the world where intermediate-focus earthquakes occur. The recent installation of new seismic stations has improved the detection and location capabilities for earthquakes in this region. Three seismic stations belonging to this new array are located over the zone of intermediate-focus earthquakes. Analysis of recently acquired seismic data reveals a well-defined near-vertical zone of earthquake foci extending to 200 km beneath the Arakan-Yoma fold belt. On the basis of seismic, gravity and other geological data, it is suggested that this zone of earthquakes is associated with remnants of the already subducted, but not totally assimilated, Tethys oceanic lithosphere below the Burmese plate. 相似文献
62.
63.
S. Gupta 《洁净——土壤、空气、水》1987,15(2):185-192
The fish Cyprinus carpio (HAM.) and Channa punctatus (BL.) of the size ranging between 6.0 ± 1.2 cm and 28.0 ± 1.6 cm were exposed to different concentrations of industrial effluents from M/s Punjab Tannery Ltd. (Jalandhar), M/s Spinning Mill Ltd. (Hoshiarpur) and M/s Food Specialist Ltd. (Moga) for evaluating the influence of fish size on the acute toxicity of these effluents. Results indicate that the relative toxicity of the effluents decreased with the increase in fish size from 6.0 ± 1.2 cm to 20.6 ± 1.5 cm. However, for specimens of the size of 28.0 ± 1.6 cm and more, the toxicity of the effluents increased with an increase in fish size. On the basis of the relative toxicity to fish, effluent from Punjab Tannery was found highly toxic and from Food Specialist Industry, the least toxic. 相似文献
64.
The relative toxicities of seven non insecticidal chemicals to Mesocyclops leuckarti were tested. The relative toxicity of each chemical is given as under: Chlorine water > Potassium permanganate > Cetavlon > Quicklime > Common alum > Savlon > Sodium bicarbonate. 相似文献
65.
A three-dimensional hybrid model for the analysis of soil-structure interaction under dynamic conditions is developed which takes advantage of the desirable features of the finite element and substructure methods and which minimizes their undesirable features. The modelling is achieved by partitioning the total soil-structure system into a near-field and a far-field with a hemispherical interface. The near-field, which consists of the structure to be analysed and a finite region of soil around it, is modelled by finite elements. The semi-infinite far-field is modelled by distributed impedance functions at the interface which are determined by system identification methods. Numerical results indicate that the proposed model makes possible realistic and economical assessment of three-dimensional soil-structure interaction for both surface and embedded structures. 相似文献
66.
S.B. Rakesh Kumar Singh Mohan L. Gupta G.V. Rao 《Journal of Volcanology and Geothermal Research》1982,13(3-4)
Direct current resistivity surveys and shallow temperature measurements were carried out for geothermal exploration in a part of Parvati valley, goethermal field, Himachal Pradesh, India. At a few places, the Schlumberger soundings pointed to the presence of a relatively low-resistivity shallow layer, which probably represents fractured and jointed quartzite, saturated with hot/cold water. Wenner resistivity profiles indicate the presence of some possible shallow subsurface lateral hot water channels across the valley at Manikaran. Shallow temperature measurements show a good subsurface thermal anomaly near the confluence of the rivers Brahmaganga and Parvati. The results of the survey, together with other available geodata, suggest that an anomalous heat source does not lie beneath the study area.It is postulated that the meteoric water, originating at high elevations after heating as a result of circulation at depth, emerges at the surface in the Parvati valley as hot springs, after mixing in various proportions with near surface cold waters. 相似文献
67.
Gupta H.K. and Singh V.P., 1982. Is Shillong region, northeast India, undergoing a dilatancy stage precursory to a large earthquake? In: A.L. Hales and Z. Suzuki (Editors), Earthquake Prediction. Tectonophysics, 85: 31–33. 相似文献
68.
Shahriar M. Wahid Mukand S. Babel Ashim Das Gupta Roberto S. Clemente 《Hydrogeology Journal》2007,15(2):365-382
In Bangladesh, development of the groundwater resource for irrigation is a vital component of the government’s agricultural
strategy to attain food self-sufficiency. Amidst reports of falling groundwater levels in many parts of Bangladesh, the potential
of groundwater use has been investigated in the Teesta Barrage Project (TBP) in which large-scale groundwater development
for dry-season irrigation has taken place in the recent past. Several techniques and tools have been applied such as the combination
of analysis of groundwater hydrographs and mathematical modelling to derive key hydrogeological variables, calculation of
net irrigation requirement and the use of geographical information systems. The results show that the economically attractive
high-yielding variety (HYV) Boro (dry season) rice cultivation during the groundwater irrigation season may not be sustained in large parts of the project
area if the current trends in abstraction are continued. However, due to spatial variation in abstraction, nine thanas (sub-districts)—out of a total of 21 in the project area—may still be able to expand groundwater-irrigated cropland and a
groundwater-use potential of 40 mm/year may be created if deep-set shallow tubewells are used by the farmers to abstract groundwater.
A structured approach, based on zoning of potential areas, is recommended for groundwater development and use.
Resumen En Bangladesh, el desarrollo de las aguas subterráneas para riego es un componente vital del la estrategia agrícola del Gobierno para obtener la auto-suficiencia alimentaria. Un informe intermedio evidencia un descenso de los niveles de aguas subterráneas en muchas partes de Bangladesh, el uso potencial de aguas subterránea ha sido investigado en el Proyecto Tessta Barrage (TBP) en el cual ha tenido lugar el desarrollo de las aguas subterráneas a gran escala para el riego en la estación seca en un pasado reciente. Se ha aplicado algunas técnicas y herramientas, como la combinación del análisis de datos gráficos de aguas subterráneas y modelización matemática para obtener variables hidrogeológicas clave, el cálculo de la necesidad neta de riego y el uso de Sistemas de Información Geográfica. El resultado muestra que el cultivo, económicamente atractivo, de arroz HYV Boro (estación seca) durante la estación de riego con aguas subterráneas puede no ser sostenible en gran parte del área del proyecto si continúan las tendencias actuales en las extracciones. Sin embargo, debido a la variación espacial en la extracción, nueve thanas (subdistritos)—de un total de 21 en el área del Proyecto—pueden todavía sufrir un aumento de la tierra cultivable regada con aguas subterráneas y que se puede asumir un uso potencial de agua subterránea de 40 mm/estación si los granjeros utilizan sondeos someros instalados en fosas para la extracción. Se recomienda una aproximación estructurada para el desarrollo y uso de las aguas subterráneas, basada en la zonificación de áreas potenciales.
Résumé Au Bangladesh, l’exploitation des ressources en eau souterraines pour l’irrigation est une composante vitale de la stratégie agricole gouvernementale pour atteindre l’auto-suffisance alimentaire. Parmi les baisses de niveaux piézométriques rapportées sur de nombreuses régions du Bangladesh, le potentiel d’utilisation des eaux souterraines a été étudié sur le Projet de Barrage de Teesta (TBP), où, dans un passé récent, les eaux souterraines ont été massivement exploitées pour l’irrigation en saison sèche. De nombreux outils et techniques ont été utilisés, comme l’analyse combinée des chroniques piézométriques et des modèles mathématiques pour dégager les variables hydrogéologiques clés, le calcul des besoins nets pour l’irrigation, et l’utilisation des systèmes d’information géographique. Les résultats démontrent que la culture en saison d’irrigation de la variété de riz HYV Boro (saison sèche), économiquement attrayante, n’est potentiellement pas viable sur de nombreux secteurs de la zone étudiée si les prélèvements perdurent selon la tendance actuelle. Cependant, du fait de la variation spatiale des prélèvements, neuf thanas (sous-districts)—sur un total de 21 sur le secteur d’étude—pourraient encore augmenter les surfaces irriguées, et une disponibilité en eau de 40 mm/saison pourrait être générée si les agriculteurs utilisaient des puits peu profonds pour exploiter les ressources souterraines. Une approche structurée, basée sur le zonage des secteurs potentiels, est recommandée pour l’exploitation et l’utilisation des eaux souterraines.相似文献
69.
S. Abhilash Someshwar Das S. R. Kalsi M. Das Gupta K. Mohankumar John P. George S. K. Banerjee S. B. Thampi D. Pradhan 《Pure and Applied Geophysics》2007,164(8-9):1491-1509
Pre-monsoon rainfall around Kolkata (northeastern part of India) is mostly of convective origin as 80% of the seasonal rainfall
is produced by Mesoscale Convective Systems (MCS). Accurate prediction of the intensity and structure of these convective
cloud clusters becomes challenging, mostly because the convective clouds within these clusters are short lived and the inaccuracy
in the models initial state to represent the mesoscale details of the true atmospheric state. Besides the role in observing
the internal structure of the precipitating systems, Doppler Weather Radar (DWR) provides an important data source for mesoscale
and microscale weather analysis and forecasting. An attempt has been made to initialize the storm-scale numerical model using
retrieved wind fields from single Doppler radar. In the present study, Doppler wind velocities from the Kolkata Doppler weather
radar are assimilated into a mesoscale model, MM5 model using the three-dimensional variational data assimilation (3DVAR)
system for the prediction of intense convective events that occurred during 0600 UTC on 5 May and 0000 UTC on 7 May, 2005.
In order to evaluate the impact of the DWR wind data in simulating these severe storms, three experiments were carried out.
The results show that assimilation of Doppler radar wind data has a positive impact on the prediction of intensity, organization
and propagation of rain bands associated with these mesoscale convective systems. The assimilation system has to be modified
further to incorporate the radar reflectivity data so that simulation of the microphysical and thermodynamic structure of
these convective storms can be improved. 相似文献
70.
M. C. Gupta V. P. Krishnarajan Shailesh Nayak 《Journal of the Indian Society of Remote Sensing》2001,29(1-2):79-83
Aquaculture has emerged as one of the fast growing industries in the developing countries both for domestic consumption as well as for the export. This industry not only generates foreign exchange to the country but also provides employment opportunities to the skilled and unskilled rural poor. On the other hand, aquaculture has also some negative impacts on the environment which are mainly due to conversion of mangroves and agricultural, salination of surface water resources and agricultural land at some places besides causing pollution and diseases. All the major shrimp farming countries of the world have faced environmental problem due to intensification, improper and uncontrolled planning by greed and unlimited profit motives of a section of aquaculture community. In view of this, a proper environmental management is a basic need to sustain the industry in the long run. Selection of a suitable site in the coastal areas is the first and the foremost step which is a crucial factor in determining the success of shrimp farming. The present paper discusses the selection of brackish water aquaculture sites using remote sensing satellite data and GIS on the Cannanore coast. Different aquaculture sites in the area were evaluated using a GIS package. Finally a prioritization map showing the sites in the descending order of their priority was generated. 相似文献