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911.
Anil Kumar Singh Virendra Singh K. K. Singh Jayant Nath Tripathi Amit Kumar Anil Kumar Soni M. Sateesh Chinmay Khadke 《Journal of the Indian Society of Remote Sensing》2018,46(6):927-935
India Meteorological department (IMD) used INSAT-3D Metrological Satellite Imager data to drive two type rainfall estimation products viz-Hydro Estimate (HE) and INSAT Multi-Spectral Rainfall Algorithm (IMSRA) on half hourly rainfall rate and daily accumulated rainfall in millimeter (mm). Integrated Multi-Satellite Retrieval for GPM (IMERG) product is being derived by NASA and JAXA by using Global Precipitation Mission (GPM) satellites data. IMSRA and GPM (IMERG) are gridded data at 10 km spatial resolution and HE is available at pixel level (4 km at Nadir). IMD provides gridded rainfall data at 0.25° × 0.25° resolution which is based on wide coverage of 6955 actual observation. In present study, validation of INSAT-3D based Hydro Estimator (HE), INSAT Multi-Spectral Rainfall Algorithm (IMSRA) and Integrated Multi-Satellite Retrieval for GPM (IMERG) of Global Precipitation Mission (GPM) satellites are carried out with IMD gridded data set for heavy rainfall event during winter monsoon, over peninsular India (November–December 2015). In validation, Nash–Sutcliffe efficiencies (NSE), RMSE, Correlation, Skilled scores are calculated at grid level for heavy and very heavy rain categories and the values of NSE of HE (? 32.36, ? 3.12), GPM (? 68.67, ? 2.39) and IMSRA (? 0.02, 0.28) on 16th November 2015 and HE (? 13.65, ? 1.69), GPM (? 43.79, ? 2.94) and IMSRA (? 1.08, ? 1.60) on 2nd Dec 2015, for heavy and very heavy rainfall. On both days, HE is showing better rainfall estimate compare to GPM for Heavy rainfall and GPM showing better estimation for very heavy rainfall events. In all the cases IMSRA is underestimating, if daily rain fall exceeded 75 mm. 相似文献
912.
Ajeet Kumar Vishwakarma Rajendra Prasad Dileep Kumar Gupta Pradeep Kumar Varun Narayan Mishra 《Journal of the Indian Society of Remote Sensing》2018,46(6):973-980
The present study describes the ground based bistatic scatterometer measurements of ladyfinger crop at its various growth stages in the specular direction with the azimuthal angle (\( \phi = 0 \)) for the angular incidence angle ranging from 20° to 60° at the interval of 10° at HH and VV polarization. An outdoor ladyfinger crop bed of an area 4 × 4 m2 was specially prepared for the ground based bistatic scatterometer measurements. The crop growth variables like vegetation water content, leaf area index, fresh biomass, and plant height were also measured at the time of each bistatic scatterometer measurement. The specular bistatic scattering coefficients were found to be decreasing with the crop growth variables up to the maturity stage and then after it increased slightly. The linear regression analysis was carried out between specular bistatic scattering coefficient and crop growth variables at all the incidence angles for HH and VV polarization to select the optimum angle of incidence and polarization for the estimation of crop growth variables. The potential of subtractive clustering based adaptive neuro-fuzzy inference system was applied for the estimation of crop growth variables. The estimated values for different crop growth variables were found almost close to the observed values. 相似文献
913.
Stutee Gupta Arijit Roy Dhruval Bhavsar Rajkanti Kala Sarnam Singh A. Senthil Kumar 《Journal of the Indian Society of Remote Sensing》2018,46(6):945-955
The hills of Uttarakhand witness forest fire every year during the summer season and the number of these fire events is reported to have increased due to increased anthropogenic disturbances as well as changes in climate. These fires cause significant damage to the natural resources which can be mapped and monitored using satellite images by virtue of its synoptic coverage of the landscape and near real time monitoring. This study presents burnt area assessment caused by the fire episode of April 2016 to the forest vegetation. Digital classification of satellite images was done to extract the burnt area which was found to be 3774.14 km2, representing 15.28% of the total forest area of the state. It also gives an account of cumulative progression of forest fire in Uttarakhand using satellite images of three dates viz. 23rd, 27th May and 2nd June, 2016. Results were analyzed at district, administrative and forest division level using overlay analysis. Separate area statistics were given for different categories of biological richness, forest types and protected areas affected by forest fire. The burnt area assessment can be used in mitigation planning to prevent drastic ecological impacts of the forest fire on the landscape. 相似文献
914.
The Singrauli region is known for fluoride contamination and its effect on human population. In this work the possible sources of fluoride contamination in Rihand reservoir water is constrained. They include slurry water, fly ash and coal samples of various thermal power plants, coal seams and granites of the region. Petrographic study depicted the presence of fluoride bearing minerals - flour apatite in pink granite. Preliminary scanning electron microscope studies revealed presence of fluorine peak in coal samples. The chemical analysis confirmed the presence of fluoride in fly ash (12.6 mg/kg), drain water (5.34 mg/l), soil (6.1 mg/kg), coal (3.1 mg/kg). They confirmed the source of fluoride from coal of thermal power plant which utilized coal from Singrauli coal seam (1.6 mg/kg). Further the Rihand reservoir water is also enriched by fluoride contaminant (upto 4.7 mg/l). This contaminates groundwater of the area as well. The contaminated water used for drinking and agriculture affects health of inhabitants in the area. It is concluded that the main source of fluoride contamination in the study area is due to coal burnt in thermal power plant and pink granite formation of the area, both anthropogenic and geogenic sources are implied. 相似文献
915.
An ensemble of spatially associated high level magma intrusives comprising dykes, laccolith and vent have been identified near Gani inlier in the Kurnool sub-basin. Geological setting, morphology of igneous intrusives and their relationships with the sediment cover have been documented. Diabase in laccolith, dykes and vesicular basalt in vents are prominent rocks and have been subjected to extensive deuteric alterations viz. saussurtisation and uralitisation. It is envisioned that the basic magma was intruded as dykes in strike-slip fault domain, outpoured through the vents as vesicular basalts at the intersection zones of cross faults. The vertical ascending melt was deflected as a sheet due to fault control at a sub-surface level of ~700m along the lithological discontinuities in country rock sediments. The sheet to laccolith transition has resulted in the uplift of older Tadpatri Formation as an inlier amidst the Neoproterozoic Kurnool sediment cover. The localization of iron ore and copper mineralization adjacent to intrusives is attributed to late stage melt-fluid activity associated with the igneous activity. Based on field relationships it is suggested that the high level magmatic activity had occurred after the Kurnool sedimentation in this part of the Kurnool sub-basin. 相似文献
916.
Girish Gopinath Resmi T. R. Anil Kumar K. S. Anusree N. S. N. B. Narasimha Prasad 《Journal of the Geological Society of India》2018,91(2):198-200
This paper discusses the ancient perennial water abstraction structures—Keni—developed by the tribal communities in Wayanad district, Kerala, southwest coast of India. Keni is shallow wooden abstraction structure built in the soil zone where the water table is near or above the ground level. These traditional water abstraction structures are perfect example of water harvesting and water purification. As a preliminary assessment, a detailed survey of the Keni in the district is conducted and the result of the chemical analysis of water from the Keni is presented in this paper. Water from Kenis meet the drinking water quality standards prescribed by the BIS. 相似文献
917.
B. Nagaraju Sachin S. Ghodke K. Rathna Gaurav J. Kokandakar Laxman B. More Munjaji V. Bhosle K. Vijaya Kumar 《Journal of the Geological Society of India》2018,91(3):263-272
Formation of the fragments of the wall-rock during dyking is one of the important manifestations of instantaneous magmatic events. This process is well documented at shallower depths of Earth’s crust but not at deeper levels. In this paper the in situ xenoliths of host rock nepheline syenite within a micro-shonkinite dyke emplaced at mid-crustal depths is described and the fractal theory applied to evaluate origin of the xenoliths. The nepheline syenite xenoliths are angular to oval shaped and sub-millimetre to ~50 cm long. The xenoliths are matrix supported with clasts and matrix being in equal proportions. Partly detached wall-rock fragments indicate incipient xenolith formation, which suggested that the model fragmentation processes is solely due to dyke emplacement. Fractal analytical techniques including clast size distribution, boundary roughness fractal dimension and clast circularity was carried out. The fractal data suggests that hydraulic (tensile) fracturing is the main process of host rock brecciation. However, the clast size and shape are further affected by postfragmentation processes including shear and thermal fracturing, and chemical erosion. The study demonstrates that dyking in an isotropic medium produces fractal size distributions of host rock xenoliths; however, post-fragmentation processes modify original fractal size distributions. 相似文献
918.
Carbon isotope (δ13C) and rare earth element (REE) concentrations in representative samples of the shallow marine Subathu Formation, explored from the Neelkanth and Dogadda sections of Northwestern Himalaya (India) were determined to infer the palaeo-environmental condition during the late Paleocene and middle Eocene. δ13C values show variation of ~5.0‰ with maximum excursion (?27.34‰) in calcareous sandstone at the basal part and minimum (?22‰) in red shale towards the terminal end. Total REE concentration varies (due to lithology) from 27.23?ppm to 564.35?ppm with an average of 187.60?ppm. The chondrite and PAAS normalized patterns exhibit positive Ce anomaly (0.95–4.45), enriched LREE, and depleted HREE, medium Y/Ho ratio (~30–45) along with positive correlation between Y/Dy and Y/Ho ratio. In addition, calcite veins present in some shale samples indicate redox sensitive trace elements. The overall REE abundance and distribution suggests highly oxygenated environment under the shallow marine regressive phase of deposition. The depositional setting, biostratigraphical constrained age along with δ13C values and lower TOC suggested an intense warm period, that might be coeval with the Paleocene-Eocene Thermal Maxima event (PETM). 相似文献
919.
Sandip More Rajarshi Rit Mahasin Ali Khan Dipak Kumar Paruya Suchana Taral Tapan Chakraborty Subir Bera 《Journal of the Geological Society of India》2018,91(3):301-306
Fossil leaf impressions and pollen grains comparable to modern Sloanea sp. of Elaeocarpaceae collected from the middle part of the Siwalik sediments (Geabdat Sandstone Formation; Pliocene) in Darjeeling foothills of eastern Himalaya are reported in the present communication. On the basis of macro morphological features, leaf remains are described as a new species Sloanea siwalika sp. nov. This is the first authentic record of the occurrence of leaf and pollen grains comparable to the genus Sloanea L. from the Cenozoic sediments of India and Asia as well. The recovery of this species and other earlier-described evergreen taxa from the same formation, suggests the existence of a tropical, warm and humid climatic conditions during the depositional period. The present study further suggests that after Pliocene the taxon might have shifted from Darjeeling Himalayan region to the adjoining southeast Asian land masses, due to possible climate change caused by post-Pliocene orogenic movement of the Himalaya. 相似文献
920.
H. K. Pandey Shivam Dwivedi Kamlesh Kumar 《Journal of the Geological Society of India》2018,92(3):286-290
Flood is common phenomena worldwide since time immemorial. Recently the change in climatic parameters has drastically affected the pattern and magnitude of flood. India being one of the tropical country face flood and drought situations every year, therefore it needs accurate assessment and forecast of flood for proper management of natural resources.An attempt has been made through the present study which consists frequency analysis on maximum daily discharge data in Betwa river at Basoda, Mohana and Shahijina gauging stations in Madhya Pradesh state using Gumbel’s Extreme value distribution and Log Pearson Type-3 distribution for 20 years period (1993-2012).The result shows that Log Pearson Type-3 distribution is better suited for Betwa basin. The results can be used by civil engineers for deciding the dimensions of hydraulic structures such as spillways, dams, bridges etc. Floods are forecasted for the different return periods for Betwa river. 相似文献