Metamorphic evolution of the contact aureole of the Jhirgadandi pluton, Sonbhadra district, Mahakoshal mobile belt, central India     

S P SINGH  ANAND K SRIVASTAVA  GOPENDRA KUMAR  S B DWIVEDI 《Journal of Earth System Science》2013,122(3):743-757

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Soil gas radon–thoron monitoring in Dharamsala area of north-west Himalayas, India using solid state nuclear track detectors     

GULSHAN KUMAR  ARVIND KUMAR  VIVEK WALIA  JITENDER KUMAR  VIKASH GUPTA  TSANYAO FRANK YANG  SURINDER SINGH  BIKRAMJIT SINGH BAJWA 《Journal of Earth System Science》2013,122(5):1295-1301

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Reflection of plane waves in an initially stressed perfectly conducting transversely isotropic solid half-space     

BALJEET SINGH  ANAND KUMAR YADAV 《Journal of Earth System Science》2013,122(4):1045-1053

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Snow and glacier melt in the Satluj River at Bhakra Dam in the western Himalayan region     

PRATAP SINGH  S. K. JAIN 《水文科学杂志》2013,58(1):93-106

Abstract

Streamflow in the Himalayan rivers is generated from rainfall, snow and ice. The distribution of runoff produced from these sources is such that the streamflow may be observed in these rivers throughout the year, i.e. they are perennial in nature. Snow and glacier melt runoff contributes substantially to the annual flows of these rivers and its estimation is required for the planning, development and management of the water resources of this region. The average contribution of snow and glacier melt runoff in the annual flows of the Satluj River at Bhakra Dam has been determined. Keeping in view the availability of data for the study basin, a water balance approach was used and a water budget period of 10 years (October 1986-September 1996) was considered for the analysis. The rainfall input to the study basin over the water budget period was computed from isohyets using rainfall data of 10 stations located at different elevations in the basin. The total volume of flow for the same period was computed using observed flow data of the Satluj River at Bhakra Dam. A relationship between temperature and evaporation was developed and used to estimate the evapotranspiration losses. The snow-covered area, and its depletion with time, was determined using satellite data. It was found that the average contribution of snow and glacier runoff in the annual flow of the Satluj River at Bhakra Dam is about 59%, the remaining 41% being from rain.  相似文献   

EXPERIMENTAL STUDY ON BED SHEAR STRESS AND SEDIMENT TRANSPORT IN A MEANDERING LABORATORY CHANNEL     

L. YILMAZ  Vijay P. SINGH  S.K. MISHRA  D. D. ADRIAN  J. J. SANSALONE Civil Engineering Faculty  Hydraulic Division  Technical University of Istanbul    Maslak  Istanbul  Turkey 《国际泥沙研究》2002,17(1)

1 INTRODUCTION River erosion is a complex phenomenon. The rate of bank retreat is determined by flow, bed topography, sediment transport, bank properties, and water quality. Prediction of future river planform changes and the knowledge of river erosion and river meandering are required for land use planning in alluvial river valleys and determining locations for bridges and hydraulic structures. The control of riverbank erosion requires prediction of flow and bed features in a meanderin…  相似文献   

Thermal perturbation during charnockitization and granulite facies metamorphism in southern India   总被引：1，自引：0，他引：1  

J. GANGULY  R. N. SINGH  D. V. RAMANA 《Journal of Metamorphic Geology》1995,13(3):419-430

Abstract We have deduced the steady-state lithospheric geotherm at c. 1 Ga in the south Indian shield area using the available data on the concentration of radioactive elements, and the P-T conditions of Proterozoic mantle xenoliths in the south Indian kimberlites as constraints. The geotherm was adjusted back to 2.5 Ga by keeping the surface temperature constant and calculating the temperature change at the top of convecting upper mantle. The reduced or mantle heat flux, which was treated as an adjustable parameter, was 20.9–21.3 mW/m² at 1–2.5 Ga. Comparison of the calculated steady-state geotherm with the available P-T data of the Archaean (c. 2.5 Ga) charnockites and granulites from southern India suggests that the granulite facies metamorphism in this region had resulted from a major thermal perturbation, which was c. 400° C at 25 km. Seismic tomographic and gravity data essentially preclude any significant magma underplating of the granulitic crust in southern India. Previous workers have suggested that the formation of charnockites in this region was associated with copious CO₂ influx from a deep-seated source, possibly the mantle. In this work, we have evaluated both the transient and steady-state thermal effects of the heat convected by CO₂ outgassing from upper mantle. It is shown that the thermobarometric array of charnockites and granulites can be produced by the convective perturbation of the steady-state geotherm, and that a flux of CO₂ of ±90 mol/m² yr (corresponding to Darcy velocity of ±0.30 cm/yr) for a period of ±30 Ma was needed to produce the required perturbation. This is c. 150 times the average CO₂ flux through the tectonically active area of the Earth's crust at the present time. There is, however, an uncertainty of a factor of 3 in this value. Seismic tomographic and gravity data independently suggest thickening of the crust beneath the granulite terrane compared with the adjacent Dharwar craton. This suggests thermal perturbation due to overthrusting as a major potential cause for the granulite facies metamorphism in south India. Overthrusting of a 30–35-km-thick thrust block was needed to produce the required thermal effect. The estimated thickness of the original crust from geobarometric and seismic tomographic data south of the orthopyroxene isograd or ‘transition zone’is compatible with the emplacement of a thrust block of this magnitude. However, the latter fails to match the estimated pre-uplift crustal thickness at the transition zone, if it is assumed that the crust has not thinned by non-erosional processes since the Archaean. Thus, we propose a combination of overthrusting and CO₂ fluxing from a deep-seated source as the cause for the formation of charnockites in this zone. The required focusing of CO₂ in this case is c. 40% of that estimated in the model where CO₂ fluxing was considered to be the sole reason for thermal perturbation. This combined thrusting—CO₂ fluxing model also helps explain the development of patchy charnockites in the transition zone from amphibolite facies rocks.  相似文献   

REPLY TO COMMENTS BY F.D. MORGAN*     

RAMESH P. SINGH 《Geophysical Prospecting》1987,35(5):620-621

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SEPARATION OF TWO-DIMENSIONAL RESIDUAL GRAVITY ANOMALIES USING LATERAL DENSITY VARIATION *     

J. SINGH  S. C. GARDE 《Geophysical Prospecting》1974,22(1):68-75

A set of parabolae is defined to approximate the observed gravity profile for specifying the lateral density variation in a two dimensional causative body. This variation separates the “biased” as well as “unbiased” residual anomaly structure. The method may be directly incorporated into existing numerical and graphical techniques of interpretation for subsequent delineation of structural configuration. The simple relations derived by inspection of the observed gravity profile permit universal application of the technique and in particular for the determination of the size and shape of sub-shelf structures. The suitability of the method in various problems of two dimensional interpretation has been indicated through an illustration of the Godavari Basin (India).  相似文献   

LONGITUDINAL DISPERSION IN OPEN-CHANNEL FLOW     

U.P. SINGH  R.J. GARDE  and K.G. RANGA RAJU 《国际泥沙研究》1992,(2)

Laboratory experiments on longitudinal dispersion in clear-water and sedimentladen flows are reported. These experiments indicate that the presence of suspended sediment does not have a significant effect on the dispersion process other than its possible effect on the friction factor. Analysis of the writers' and other's data collected in laboratory flumes and natural streams Shows that Taylor's model of longitudinal dispersion based on one-dimensional Fickian diffusion equation with a constant dispersion coefficient, DL, is not suitable for describing the dispersion process in natural streams as DL tends to increase in the downstream direction. Therefore, a similarity analysis of the concentration distributions, on the lines of Day and Wood, has been carried out. Based on dimensional analysis an improved empirical method has been obtained for predicting the concentration-time relation without the use of DL  相似文献   

GENESIS OF LAMINATED SAND AND GRADED RHYTHMITES IN STORM-SAND LAYERS OF SHELF MUD     

H. E. REINECK  INDRA B. SINGH 《Sedimentology》1972,18(1-2):123-128

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