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K. Satish Kumar S. Parveen Begum G. S. Srinivas M. Shri Hari Rao P. Prabhakara Prasad T. Seshunarayna R. K. Tiwari 《Journal of the Geological Society of India》2018,92(3):368-372
Ajmer-Sambar sector of Delhi fold belt, North-Central Rajasthan has got importance due to its litho characters, structure, metamorphism, magmatism, migmatisation, metallogeny and rich potential of base metal mineralization. This sector is comprised of Delhi sequence of rocks hosted by the Banded Gneisses Complex (BGC). In view of the significance of this region, ground magnetic survey was conducted along six regional profiles to understand the structural features, magnetic nature of the basement and depth to the basement. Analysis of the magnetic data has clearly identified two magnetic lineaments (a) L1 in WNW-ESE direction that appears to represent litho-contact between Kalyanpura sequences in the south to Anasagar migmatite in the north and (b) L2 in NNW to SSE direction south of Parvatsar which is inferred to be a structural control about which the quartzite rocks of Taragarh Formation culminate. An average depth to basement of 3.7 km is estimated through spectral analysis of magnetic data. The maximum depth of the basin 4.5 km is estimated in central part of the study area. The obtained depth results are in good agreement with the Cummulative Total Intensity Magnetic Anomaly field (CTIMAF) and Deep seismic stuides. 相似文献
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A decadal historical satellite data analysis for flood hazard evaluation: A case study of Bihar (North India) 
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下载免费PDF全文 Panchagnula Manjusree Chandra Mohan Bhatt Asiya Begum Goru Srinivasa Rao Veerubhotla Bhanumurthy 《Singapore journal of tropical geography》2015,36(3):308-323
Flood is one of the major recurrent natural disasters faced by the state of Bihar in north India. In the present study the authors assess the severity of flood hazard in Bihar, using 128 decadal historical satellite datasets acquired during different flood magnitudes during 1998 to 2010. The satellite‐based observations have been analysed in conjunction with the hydrological data, for assessing the frequency of inundation, severity of flood hazard and cropped land under flood hazard. This study assesses the spatial distribution of flooding and creation of systematic flood hazard database, which can be analysed from a spatial dimension in GIS. It is observed that about 24.56 lakh ha of the state's area and about 15.85 lakh ha of the cropped area are vulnerable to flood hazard. North Bihar is more vulnerable to flooding; 8 of the 10 areas identified as worst flood‐affected districts lie in this region. 相似文献
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Damage and management of cyclone Sidr-affected homestead tree plantations: a case study from Patuakhali, Bangladesh 总被引：1，自引：0，他引：1
Md. Zamiul Haq Mahbub Robbani Mohammad Ali Md. Mainul Hasan Md. Mahmudul Hasan Md. Jashim Uddin Monjila Begum Jaime A. Teixeira da Silva Xiao-Ying Pan Md. Rezaul Karim 《Natural Hazards》2012,64(2):1305-1322
Geographically, Bangladesh is considered to be one of the most cyclone-prone areas in the world. The super cyclone Sidr in 2007 was one of the most devastating disasters to have ever occurred in Bangladesh, having wind speeds of 223?km/h with a tidal surge of 6.1?C7.6?m high. In order to draw a pre- and post-Sidr damage and management scenario, a survey was conducted at Dumki upazila, Patuakhali district in Bangladesh with a pretested questionnaire. Primary data were collected through a questionnaire, while secondary data were collected from pertinent offices as well as academic journals. The major focus of this study was to assess the state of pre-Sidr tree plantations (woody and fruit trees), the devastation caused by Sidr on these tree plantations, and post-Sidr recovery and further sustainable management initiatives to counteract a possible future neo-Sidr. The post-Sidr study showed that about 16.84 million woody and fruit trees were uprooted by Sidr. A total of 3,120 rain tree (Samanea saman L.), 7,548 mahogany (Swietenia mahagoni L.), 1,444 royal siris (Albizzia richardiana L.), 702 white siris (Albizzia procera L.), 1,214 mango (Mangifera indica L.), 1,092 coconut (Cocos nucifera L.), 1,380 jackfruit (Artocarpus heterophyllus L.), and 7,640 betel nut (Areca catechu L.) trees were sampled among which 922, 1,662, 382, 210, 106, 38, 362, and 1,652 trees, respectively, were markedly damaged by Sidr. Sexually propagated woody trees with a damaged taproot were vulnerable to heavy wind during the cyclone. Fruit trees were more resistant to the cyclone than other types of trees, and the lack of proper tree training and pruning was one of the principal causes of the severe damage to woody trees. Hence, plantations of woody tree saplings with damaged taproots are strongly discouraged. However, proper training and pruning of homestead trees together with plantation of fruit trees rather than woody trees is suggested as a possible effective management strategy to protect the homestead ecosystem from devastation by future cyclones in Bangladesh. 相似文献
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S. S. Sreekumar P. Vinod Essy Samuel J. P. Malkar A. R. Rao M. K. Hingar V. P. Madhav D. Debnath T. B. Kotoch Anuj Nandi S. Shaheda Begum Sandip Kumar Chakrabarti 《Experimental Astronomy》2011,29(1-2):109-133
The onboard software and data communication in the RT-2 Experiment onboard the Coronas?CPhoton satellite is organized in a hierarchical way to effectively handle and communicate asynchronous data generated by the X-ray detectors. A flexible data handling system is organized in the X-ray detector packages themselves and the processing electronic device, namely RT-2/E, has the necessary intelligence to communicate with the three scientific payloads by issuing commands and receiving data. It has direct interfacing with the Satellite systems and issues commands to the detectors and processes the detector data before sending to the satellite systems. The onboard software is configured with several novel features like (a) device independent communication scheme, (b) loss-less data compression and (c) Digital Signal Processor. Functionality of the onboard software along with the data structure, command structure, complex processing scheme etc. are discussed in this paper. 相似文献
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Pedo and biogeochemical studies of mafic and ultramfic rocks in the Mingora and Kabal areas,Swat, Pakistan 总被引：1，自引：0，他引：1
This study highlights the heavy metals (HMs) distribution in soils and their uptake by wild plants grown in the soils derived
from the mafic and ultramafic terrains. Plant and soil samples were analyzed for Cu, Pb, Zn, Cr, Ni and Cd using atomic absorption
spectrophotometer. The data indicate that almost all the HMs in the soil samples collected from the study area exceeded the
reference and normal agricultural soils. Greater variability was noticed in the uptake of HMs by various plants grown on the
studied soils. High concentrations of Cu and Zn in Cannabis sativa L. (seft hemp), Pb in Ailanthus altissima (Mill.) (Ailanto), Ni and Cr in Indigofrra gerardiana Wall. ex Baker (sage), and Saccharum griffihii Munro ex Boiss. (plume grass) were noticed among the studied plants. The multifold enrichments of Cr and Ni in the Indigofrra gerardiana and Saccharum griffihii as compared to the other plants of the study area suggested that these plants have the ability to uptake and translocate
high concentrations of Cr and Ni. The excessive concentrations of Cr and Ni in these plants can be used for mineral prospecting
but their main concern could be of serious environmental problems and health risks in the inhabitants of the study areas. 相似文献
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Ayesha Begum Jayaram N. Chengalur 《Monthly notices of the Royal Astronomical Society》2005,362(2):609-611
We present a deep Giant Metrewave Radio Telescope (GMRT) search for H i 21-cm emission from three dwarf galaxies, viz. POX 186, SC 24 and KKR 25. Based, in part, on previous single-dish H i observations, these galaxies have been classified as a blue compact dwarf (BCD), a dwarf irregular and a transition galaxy, respectively. However, in conflict with previous single-dish detections, we do not detect H i in SC 24 or KKR 25. We suggest that the previous single-dish measurements were probably confused with the local Galactic emission. In the case of POX 186, we confirm the previous non-detection of H i but with substantially improved limits on its H i mass. Our derived upper limits on the H i mass of SC 24 and KKR 25 are similar to the typical H i mass limit for dwarf spheroidal (dSph) galaxies, whereas in the case of POX 186, we find that its gas content is somewhat smaller than is typical of BCD galaxies. 相似文献
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