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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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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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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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   

Numerical study of mechanism of fold formation in a laminated rock     

P K SAINI  T KUMAR  T N SINGH  N SINGH  V K KESHRI 《Journal of Earth System Science》2011,120(6):965-978

A set of large deformation experiments are presented to simulate folding pattern at various energy states during formation. In order to numerically simulate this phenomenon, a rectangular layer of shale is generated and compressed at various strain rates. The results reveal the variation in distribution of stress along the length of the bed. The stress distribution during elastic behaviour of shale bed at low compression rate and the change in stress distribution leading to rupture at high compression rates is discussed. Wavelength, limb length, bulk shortening, stress distribution, displacement of particles along the length of the bed is considered for comparative study of the fold pattern generated at various compression rates. The nature and position of crack generated during the formation of fold is also explained. After rupture in shale bed, the generation of fault and stress distribution in limbs of fold sliding over one another is also described.  相似文献   

Spectral characterization of soil and coal contamination on snow reflectance using hyperspectral analysis     

S K SINGH  A V KULKARNI  B S CHAUDHARY 《Journal of Earth System Science》2011,120(2):321-328

Snow is a highly reflecting object found naturally on the Earth and its albedo is highly influenced by the amount and type of contamination. In the present study, two major types of contaminants (soil and coal) have been used to understand their effects on snow reflectance in the Himalayan region. These contaminants were used in two categories quantitatively – addition in large quantity and addition in small quantity. Snow reflectance data were collected between 350 and 2500 nm spectral ranges and binned at 10 nm interval by averaging. The experiment was designed to gather the field information in controlled conditions, and radiometric observations were collected. First derivative, band absorption depth, asymmetry, percentage change in reflectance and albedo in optical region were selected to identify and discriminate the type of contamination. Band absorption depth has shown a subtle increasing pattern for soil contamination, however, it was significant for small amounts of coal contamination. The absorption peak asymmetry was not significant for soil contamination but showed a nature towards left asymmetry for coal. The width of absorption feature at 1025 nm was not significant for both the contaminations. The percentage change in reflectance was quite high for small amount of coal contamination rather than soil contamination, however, a shift of peak was observed in soil-contaminated snow which was not present in coal contamination. The albedo drops exponentially for coal contamination rather than soil contamination.  相似文献   

Well storage effect during pumping tests in an aquifer of low permeability     

V. S. SINGH 《水文科学杂志》2013,58(4):589-594

Abstract

Well storage effect is generally considered while interpreting pumping test data from large diameter wells. However, in an aquifer of low permeability, the well storage is found to be significant during pumping tests conducted on bore wells. The interpretation of such data gives ambiguous results unless well storage effect is taken into account. A field example is presented to illustrate the difficulty in interpretation of the pumping test data. In order to take into account the well storage effect, a finite difference approach of interpreting pumping test data is suggested.  相似文献   

Nature and composition of interbedded marine basaltic pumice in the ∼52–50 Ma Vastan lignite sequence,western India: Implication for Early Eocene MORB volcanism offshore Arabian Sea     

SARAJIT SENSARMA  HUKAM SINGH  R S RANA  DEBAJYOTI PAUL  ASHOK SAHNI 《Journal of Earth System Science》2017,126(2):17

The recognition of pyroclasts preserved in sedimentary environments far from its source is uncommon. We here describe occurrences of several centimetres-thick discontinuous basaltic pumice lenses occurring within the Early Eocene Vastan lignite mine sedimentary sequence, western India at two different levels – one at ～5 m and the other at 10 m above a biostratigraphically constrained 52 Ma old marker level postdating the Deccan Volcanism. These sections have received global attention as they record mammalian and plant radiations. We infer the repetitive occurrence of pumice have been sourced from a ～52–50 Ma MORB related to sea-floor spreading in the western Arabian Sea, most plausibly along the Carlsberg Ridge. Pyroclasts have skeletal plagioclase with horsetail morphologies ± pyroxene ± Fe–Ti oxide euhedral crystals, and typically comprise of circular polymodal (radii ≤10 to ≥30 μm), non-coalescing microvesicles (>40–60%). The pumice have undergone considerable syngenetic alteration during oceanic transport and post-burial digenesis, and are a composite mixture of Fe–Mn-rich clay and hydrated altered basaltic glass (palagonite). The Fe–Mn-rich clay is extremely low in SiO ₂, Al ₂ O ₃, TiO ₂, MgO, alkalies and REE, but very high in Fe ₂ O ₃, MnO, P, Ba, Sr contents, and palagonitization involved significant loss of SiO ₂, Al ₂ O ₃, MgO and variable gain in Fe ₂ O ₃, TiO ₂, Ni, V, Zr, Zn and REE. Bubble initiation to growth in the ascending basaltic magma (liquidus ～1200–1250 ^°C) may have occured in ～3 hr. Short-distance transport, non-connected vesicles, deposition in inner shelf to more confined lagoonal condition in the Early Eocene and quick burial helped preservation of the pumice in Vastan. Early Eocene Arabian Sea volcanism thus might have been an additional source to marginal sediments along the passive margin of western India.  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   

GEOGRAPHY AS MELODY IN MUTTUSVAMI DIKSHITA'sINDIAN MUSICAL WORKS*     

CHANDRA S. BALACHANDRAN  SURINDER M. BHARDWAJ 《Geographical review》2001,91(4):690-701

ABSTRACT. The life and works of Muttusvami Dikshita (1775–1834), a luminary of South Indian Karnatak classical music, abound in spatiocultural symbolisms of integration and harmony. Dikshita'speregrinations symbolize a cultural circuit of Hindu pilgrimage. His studies of North Indian Hindustani music at Varanasi (formerly Benares), and his transplantation of them throughout South India, make him an active agent of cultural diffusion, harmonizing cultural traditions through spatiosymbolic anchors. The religious expression of his musical genius, his songs, and his melodies contributed to linking linguistically and politically disparate regions of eighteenth‐ and nineteenth‐century India. The works of Dikshita affirm India'scultural continuity and underscore its enduring cultural empathies and similarities.  相似文献