Isotopic analysis to quantify the role of the Indian monsoon on water resources of selected river basins in the Himalayas     

Ghulam Jeelani  Rouf Ahmad Shah  Rajendrakumar D. Deshpande  Ashok P. Dimri  Suraj Mal  Anupam Sharma 《水文研究》2021,35(11):e14406

Western disturbances (WDs) and Indian summer monsoon (ISM) led precipitation play a central role in the Himalayan water budget. Estimating their contributions to water resource is although a challenging but essential for hydrologic understanding and effective water resource management. In this study, we used stable water isotope data of precipitation and surface waters to estimate the contribution of ISM and WDs to the water resources in three mountainous river basins - Indus, Bhagirathi and Teesta river basins of western, central and Eastern Himalayas. The study reveals distinct seasonality in isotope characteristics of precipitation and surface waters in each river basin is due to changes in moisture source, hydrometeorology and relief. Despite steady spatial variance in the slope and intercept of regression lines from the Teesta to Indus and the Bhagirathi river basins, the slope and intercept are close to the global meteoric water line and reported local meteoric water line of other regions in the Himalayas and the Tibetan Plateau. The two-component end-member mixing method using d-excess as tracer were used to estimate the contribution from ISM and WD led precipitation to surface water in aforementioned river basins. The results suggest that the influence of the ISM on the water resources is high (>72% to annual river flow) in Teesta river basin (eastern Himalayas), while as the WDs led precipitation is dominantly contributing (>70% average annual river flow) to the surface waters in the Indus river basin (western Himalayas). The contribution of ISM and WD led precipitation in Bhagirathi river basin is 60% and 40%, respectively. The findings demonstrate that the unusual changes in the ISM and WD moisture dynamics have the potential to affect the economy and food security of the region, which is dependent on the availability of water resources. The obtained results are of assistance to policy makers/mangers to make use of the information for better understanding hydrologic response amid unusual behaviour of the dual monsoon system over the region.  相似文献   

Coronas in olivine metagabbros from the Proterozoic Chotanagpur terrain at Mathurapur, Bihar, India     

A. P. Mall  R. S. Sharma 《Lithos》1988,21(4):291-300

The Proterozoic Mathurapur olivine metagabbros possess several types of coronas due to subsolidus reactions between igneous mineral pairs. viz. olivine-plagioclase, ilmenite-plagioclase and pyroxenes-plagioclase. Microprobe analyses of coexisting primary and coronitic minerals from different corona domains, indicate attainment of equilibrium. Mineral chemical data of primary (reactants) and coronitic (products) minerals from the present metagabbros and also from similar studies in the literature are critically examined to evaluate the chemistry of corona reactions by mixing calculations assuming boundary migration. The mass-balanced corona equations are consistent with the allochemical system and do not show volume imbalance. However, SiO₂ and Al₂O₃ in olivine-plagioclase coronas remain immobile, which indicates that the corona reactions therein proceeded with minimum structural rearrangements of (Si.Al)---O bonds.  相似文献   

Temporal change detection in river courses and flood plains in an arid environment through satellite remote sensing     

Surendra Singh  K. D. Sharma  Nepal Singh  D. N. Bohra 《Journal of the Indian Society of Remote Sensing》1988,16(4):53-56

Temporal changes in ephemeral river courses and associated flood plains, which could not be detected by Landsat MSS due to its poor spatial resolution of 80m, have been identified and mapped within 10% accuracy by Landsat TM False colour composite because of its higher spectral and spatial resolution of 30 m. Over a period of 28 years (1958–86) the river courses widened upto 1.8 times through bank erosion due to the recurring flash floods. The flash floods have also caused morphological, soil fertility and landuse changes in the associated flood plains, which could also be monitored by the Landsat TM.  相似文献   

An integrated approach for ground water investigation in part of Fatehpur Sikri of district agra-a case study     

N. K. Choudhary  C. S. Agarwal  D. K. Sharma 《Journal of the Indian Society of Remote Sensing》1988,16(1):29-39

The Fatehpur Sikri area infringing the western UP, Rajasthan border was investigated for its water supply crisis in respect of poor quality and quantity as well. The study has indicated presence of two parallel quartz reefs running in NE-SW direction. Geohydrological and photogeological studies have revealed the possibility of subsurface extension of quartz reefs. However, this weathered area along reefs is promising water bearing zone. Paleo channels are also marked during studies and the area found suitable for ground water exploitation. A map showing various categories is also presented.  相似文献   

A comparative study of supervised classifiers on a subscene in Junagadh district,Gujarat     

M. P. Oza  S. A. Sharma 《Journal of the Indian Society of Remote Sensing》1990,18(3):18-24

This paper describes the results of a comparative study of five classifiers viz., maximum likelihood, modified maximum likelihood, minimum distance to mean. Fisher and min-max, for classifying a subscene of Junagadh district using Landsat Thematic Mapper (TM) data. The kappa coefficient of agreement (k) and per cent correctly classified pixels for training data are used as measures of overall performance. It is observed that maximum likelihood and modified maximum likelihood classifiers perform better than the other three classifiers for this data set. Band combinations (3, 4, S) and (2, 3, 4, S) perform better than the usual combination (1,2,3,4), possibly because of presence of middle infrared band (band 5) on a scene dominated by vegetation cover. The band combination (1, 2, 3, 4, 5, 7) performed the best.  相似文献   

Surface wave propagation in a transversely isotropic elastic layer overlying a liquid saturated porous solid half-space and lying under the uniform layer of liquid     

M. D. Sharma  Rajneesh Kumar  M. L. Gogna 《Pure and Applied Geophysics》1990,133(3):523-539

Dispersion of Rayleigh-type surface wave is studied in a homogeneous transversely isotropic elastic layer overlying a nondissipative liquid-saturated porous solid half-space and lying under a uniform layer of homogeneous liquid. The frequency equation in the form of ninth-order determinant is obtained.Special cases have been deduced by reducing the depth of the layers to zero and by changing the transverse isotropic layer to an isotropic layer. Dispersion curves for the phase velocity have been plotted for a particular model.  相似文献   

Static deformation of two welded half-spaces due to very long strike-slip dislocations     

Raj Kumar Sharma  Nat Ram Garg  Kuldip Singh 《Journal of Earth System Science》1991,100(4):379-388

Closed form analytic expressions for displacement and stresses at any point of either of the two homogeneous, isotropic, perfectly elastic half-spaces in welded contact due to very long strike-slip dislocations are obtained. Both cases of vertical and horizontal strike-slip dislocations are discussed in detail. Variation of the displacement with horizontal distance from the fault and with vertical distance from the interface for a vertical strike-slip fault is studied numerically.  相似文献   

The Indus-Tsangpo suture zone in Ladakh, northwest Himalaya: Further palaeomagnetic data and implications     

Chris Klootwijk  Madan Lal Sharma  Jozef Gergan  S.K. Shah  Biras Tirkey 《Tectonophysics》1984,106(3-4)

A total of 81 samples (244 specimens) from Upper Cretaceous Indus Molasse and Middle to Upper Cretaceous Dras Flyschoids of the Indus-Tsangpo suture zone in Ladakh (northwest Himalaya) has been studied by thermal demagnetization methods.Both formations showed a characteristic magnetization component indicative for equatorial to low northern palaeolatitudes of acquisition. Similar palaeolatitudes have been obtained before from secondary magnetization components of Early Tertiary age in the Ladakh Intrusives and in the Tibetan Sedimentary Series of central Nepal. The present characteristic components are interpreted likewise as secondary magnetizations which stabilized between 50 and 60 m.y. ago, during Greater India's collision with Asia's southern margin.The Dras Flyschoids show another magnetic component which, in case of primary origin, indicates acquisition at a low southern palaeolatitude. If correct, this interpretation supports recent suggestions for Late Cretaceous obduction of an island arc on Greater India's northern margin.  相似文献   

Paleo-uplift and cooling rates from various orogenic belts of India, as revealed by radiometric ages—reply (1)     

Kewal K. Sharma  K.D. Bal  Rajinder Prashad  Nand Lal  K.K. Nagpaul 《Tectonophysics》1984,107(1-2)

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Use of aerial photographs in mapping alkali soils with respect to their management in a part of north-west India     

R. C. Sharma  G. P. Bhargava 《Journal of the Indian Society of Remote Sensing》1987,15(1):35-39

An area of 6000 ha covering four villages was adopted by the Central Soil Salinity Research Institute, Karnal under Operational Research Project to transfer the technology of alkali soil reclamation in the farmer’s fields. This necessitated mapping and characterisation of alkali soils of the area. Use of black and white photographs in 1∶25,000 scale proved effective in delineating alkali soils quickly and inexpensively. The physiography and photo elements like tone, landuse, drainage and parcelling facilitated identification and demarcation of four mapping units viz; P₁, P₃, P₄ and C. The unit P represented nearly flat upland alluvial plain while C represented low lying filled up old channel. The alkali soils confined mainly to the upland plain were recorded in white toned barren stretches and accounted for 36.6 percent of surveyed area. In addition, patchy occurrence of alkali soils admist the cultivated fields giving mottled appearance on the photographs was noticed over 11.3 percent area. In this case the photo scale proved limiting for demarcating alkali and non-alkali soils separately. The prtactical utility of the soil inventory in planning reclamation and management of alkali soil in the area has also been discussed.  相似文献