排序方式： 共有46条查询结果，搜索用时 15 毫秒
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Priyanka Raja Hema Achyuthan K. Geethanjali Pankaj Kumar Sundeep Chopra 《Journal of the Geological Society of India》2018,91(5):547-553
A study involving grain size analysis was carried out from the Parsons valley lake deposit, Nilgiris, India to determine the depositional environments and paleoflood events since late Pleistocene period (～29,838 cal yr BP). A 72 cm lacustrine core was collected from the lake and eight organic rich sediment samples were AMS radiocarbon dated. The study reveals variations in the grain size distribution chiefly influenced by regional climatic conditions. Paleoflood events have been identified by the individual sedimentary flood signatures of varying changes in the magnitude of sediment supply from the background silty sediment matrix around ～29,838 and ～8405 cal yr BP. 相似文献
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Arjun Pandey Ishwar Singh Rajeeb Lochan Mishra Priyanka Singh Rao Hari B Srivastava R Jayangondaperumal 《Journal of Earth System Science》2018,127(5):66
The Assam Seismic Gap has witnessed a long seismic quiescence since the \({ Mw}{\sim }8.4\) great Assam earthquake of AD 1950. Owing to its improper connectivity over the last decades, this segment of the Himalaya has long remained inadequately explored by geoscientists. Recent geodetic measurements in the eastern Himalaya using GPS document a discrepancy between the geologic and geodetic convergence rates. West to east increase in convergence rate added with shorter time span earthquakes like the 1697 Sadiya, 1714 (\({ Mw}{\sim }8\)) Bhutan and 1950 (\({ Mw}{\sim } 8.4\)) Tibet–Assam, makes this discrepancy more composite and crucial in terms of seismic hazard assessment. To understand the scenario of palaeoearthquake surface rupturing and deformation of youngest landforms between the meizoseismal areas of \({ Mw}{\sim }8.1\) 1934 and 1950 earthquakes, the area between the Manas and Dhanshiri Rivers along the Himalayan Frontal Thrust (HFT) was traversed. The general deformation pattern reflects north-dipping thrust faults. However, back facing scarps were also observed in conjugation to the discontinuous scarps along the frontal thrust. Preliminary mapping along with the published literature suggests that, in the eastern Himalayan front the deformation is taking place largely by the thrust sheet translation without producing a prominent fault-related folds, unlike that of the central and western Himalayas. 相似文献
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Priyanka Singh Sameer Saran Dheeraj Kumar Hitendra Padalia Ashutosh Srivastava A. Senthil Kumar 《Journal of the Indian Society of Remote Sensing》2018,46(10):1725-1737
In this era of rapid global change, biodiversity monitoring and improving species repository to meet requirements toward conservation is costly affairs and needs a practical solution to identify and locate species with habitats. The integrated approach of citizen science and information technologies has proven to be effective solution for geographical and taxonomical data collection with public engagement, covering local to national scale. As a first step, a mobile app is designed and developed for the IBIN (Indian Bioresource Information Network), a digitized collection of the biological resources of India that serves as a common platform to access spatial and non-spatial information on biorecources can host their data through this single and intuitive platform with full privileges and authenticity. IBIN mobile app can be seen as an efficient and rapid solution to record data on species, utilizing GPS and camera features of mobile devices. Present paper deals with the citizen science approaches, its contribution in biodiversity field, outlines the design and development of IBIN mobile app and its first case study carried out at foothills of Himalaya. 相似文献
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Upper bound solutions of bearing capacity of strip footing by pseudo-dynamic approach 总被引：1，自引：0，他引：1
Priyanka Ghosh 《Acta Geotechnica》2008,3(2):115-123
This paper presents the pseudo-dynamic analysis of seismic bearing capacity of a strip footing using upper bound limit analysis.
However, in the literature, the pseudo-static approach was frequently used by several researchers to compute the seismic bearing
capacity factor theoretically, where the real dynamic nature of the earthquake accelerations cannot be considered. Under the
seismic conditions, the values of the unit weight component of bearing capacity factor N
γE are determined for different magnitudes of soil friction angle, soil amplification and seismic acceleration coefficients
both in the horizontal and vertical directions. The results obtained from the present study are shown both graphically as
well as in the tabular form. It is observed that the bearing capacity factor N
γE decreases significantly with the increase in seismic accelerations and amplification. The results are thoroughly compared
with the existing values in the literature and the significance of the present methodology for designing the shallow footing
is discussed. 相似文献
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M. V. S. GUPTHA Ran adip BANERJEE Lina P. MERGULHAO Priyanka BANERJEE G. PARTHIBAN Manish TEWARI 《《地质学报》英文版》2007,81(4):614-621
Planktic foraminifera from the calcareous substrate of a ferromanganese crust in the Vityaz Fracture Zone （VFZ）, Central Indian Ridge were studied to reconstruct the early Pliocene paleoceanography of this region. Eleven species of planktic foraminifera were encountered, among them Globorotalia menardii, Neogloboquadrina dutertrei, Globigerina bulloides and Globigerinoides tuber are prominent. Predominance of N. dutertrei in the top 3 cm of the carbonate substrate is attributed to an influx of fresh water which eventually triggered their productivity by increasing the nutrient level. The presence of G. bulloides and G. menardii in significant proportions in deeper layers suggests the prevalence of open ocean upwelling. The bulk chemical compositions of the substrate at different depth intervals indicates higher enrichment of trace metals in the upper sections which could have been supplied through oceanic water by the chemical weathering of terrestrial matter during the peak of Pliocene Asian monsoon. Thus, it is concluded that during the early Pliocene the biogenic components of the substrate were distinctly contributed by both upwelling and productivity triggered by an influx of fresh water originating from the intensification of the Asian monsoon during the early Pliocene Period. 相似文献