Quasi-static deformation of a poroelastic half-space with anisotropic permeability by two-dimensional surface loads     

Sarva Jit Singh  Sunita Rani  Raman Kumar 《Geophysical Journal International》2007,170(3):1311-1327

An analytical solution is obtained of the fully coupled diffusion–deformation system of equations governing the quasi-static plane strain deformation of a poroelastic half-space with anisotropic permeability and compressible constituents. The stresses and the pore pressure are taken as the basic state variables. Displacements are obtained by integrating the coupled constitutive relations. The problem of surface loads is discussed in detail. Explicit analytical solutions are derived for normal line loading, shear line loading and normal strip loading. The permeability anisotropy is found to have a significant effect on the quasi-static deformation of the half-space. However, in the drained and undrained limits, the anisotropy has no effect. The stresses in the drained and undrained states are independent of the poroelastic parameters. Numerical computation of the pore pressure indicates that ignoring permeability anisotropy may lead to an overestimation of the pore pressure at points vertically below the point of normal loading. Further, anisotropy in permeability may lead to a dilution in the theoretical prediction of the Mandel–Cryer Effect.  相似文献   

Chemical weathering and carbon dioxide consumption in a small tropical river catchment,southwestern India     

Nisha  Baby Krishnan  Balakrishna  Keshava  Udayashankar  Harikripa Narayana  Manjunatha  Busnur Rachotappa 《Aquatic Geochemistry》2021,27(3):173-206

Aquatic Geochemistry - Studies done on small tropical west-flowing river catchments located in the Western Ghats in southwestern India have suggested very intense chemical weathering rates and...  相似文献   

Seismic stratigraphy and the sedimentation history in the Laxmi Basin of the eastern Arabian Sea: Constraints from IODP Expedition 355     

Nisha Nair  Dhananjai K. Pandey  Anju Pandey  R. Prerna 《地学前缘(英文版)》2021,12(3):101111

Detailed interpretation of seismic stratigraphic sequences in the Laxmi Basin of the eastern Arabian Sea are presented in this study using closely spaced high resolution multi-channel seismic (MCS) data. Our stratigraphic interpretation is further corroborated using recent drilling results in the Laxmi Basin, derived from the long sediment cores collected during International Ocean Discovery Program (IODP) Expedition 355. Integrated core-log interpretation discussed in the present study, offer important insights about the lithostratigraphic variations in this region. Analyses of multi-channel seismic reflection data reveal five depositional sequences (ranging from Paleocene to Recent) that led to the development of this marginal basin since the Cenozoic period. Regional igneous basement is successfully imaged, which was also validated by deep sea coring during the IODP Expedition 355. In the present study, we primarily focus on the post-rift sedimentation in the Laxmi Basin and its possible mechanisms. Our detailed interpretation in the prevailing tectonic framework of the basin suggests that near-shelf oldest volcaniclastic sedimentation immediately overlying the acoustic basement is linked to the onset of India–Madagascar and India–Seychelles rifting activities during the Late Cretaceous period. Eventually, during the Early-Mid to Late Miocene, the basin received maximum sedimentation dominantly through an extensive mass transport mechanism implying possible large-scale deformation on the Indian shelf. Subsequent sediment input to the basin appears to have been fed variably via the Indus Fan as well as coastal discharge from the Indian mainland. The total sediment thickness in the Laxmi Basin ranges from 1.1 to 3.5 km. New stratigraphic information and sediment isopach maps presented here provide vital information about syn- and post-rift sedimentation pattern in the region and their long term tectonic implications.  相似文献   

Assessing coastal landscape vulnerability using geospatial techniques along Vizianagaram–Srikakulam coast of Andhra Pradesh,India     

Meenu Rani  Sufia Rehman  Haroon Sajjad  B. S. Chaudhary  Jyoti Sharma  Sandeep Bhardwaj  Pavan Kumar 《Natural Hazards》2018,94(2):711-725

Vizianagaram–Srikakulam coastal shoreline consisting of beaches, mangrove swamps, tidal channel and mudflats is one of the vulnerable coasts in Andhra Pradesh, India. Five site-specific parameters, namely rate of geomorphology, coastal elevation, coastal slope, shoreline change and mean significant wave height, were chosen for constructing coastal vulnerability index and assessing coastal landscape vulnerability. The findings revealed a shift of 2.5 km in shoreline towards the land surface because of constant erosion and that of 1.82 km towards the sea due to accretion during 1997–2017. The rate of high erosion was found in zones IV and V, and high accretion was found in zones II and III. Coastal vulnerability index analysis revealed constant erosion along shoreline and sea level rise in the study area. Most of the coast in zone V has recorded very high vulnerability due to erosion, high slope, significant wave height and sea level rise. Erosion and accretion, significant wave height, sea level rise and slope are attributed to high vulnerability in zones III and IV. Zone II recorded moderate vulnerability. Relatively lower slope, mean sea wave height and sea level rise have made this zone moderately vulnerable. Very low vulnerability was found in zone I, and low vulnerability was recorded in zone II. Accretion, low slope and low sea level rise were found to be causative factors of lower vulnerability. Thus, zones III, IV and V should be accorded higher priorities for coastal management. The findings can be helpful in coastal land planning and management and preparing emergency plans of the coastal ecosystems.  相似文献   

Coastal vulnerability assessment studies over India: a review   总被引：2，自引：2，他引：0  

N. N. V. Sudha Rani  A. N. V. Satyanarayana  Prasad Kumar Bhaskaran 《Natural Hazards》2015,77(1):405-428

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Dynamical instability of cylindrical symmetric collapsing star in generalized teleparallel gravity     

Abdul Jawad  Davood Momeni  Shamaila Rani  Ratbay Myrzakulov 《Astrophysics and Space Science》2016,361(4):141

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Intra-Seasonal Oscillations Associated with Indian Ocean Warm Pool and Summer Monsoon Rainfall and Their Inter-Annual Variability     

P. M. Muraleedharan  P. G. Nisha  P. V. Sathe  K. U. Sivakumar 《Journal of the Indian Society of Remote Sensing》2012,40(1):75-83

Sea surface temperature (SST) and wind speed (WS) derived from Multichannel Scanning Microwave Radiometer (MSMR), onboard IRS-P4 (Oceansat-1) satellite were used to generate spatially averaged (80° to 100° E & 0° to 10° S) daily data during June to September from 1999 to 2001 along with collocated outgoing long wave radiation (OLR) data from NCEP/NCAR reanalysis product. Daily rainfall data over the peninsular India during the above period was taken from the weekly weather report published by the Indian Meteorological Department. The data were then subjected to power spectral analysis. Dominant 30 to 60 days oscillations were observed over both ocean and land during all the 3 years investigated. It is quite interesting to note that the intra-seasonal oscillation with 60 days periodicity dominates in both ocean and land during 1999 and then transforms to 30 and 40 days periodicities in 2000 and 2001 respectively with a phase lag of about 25 to 30 days. It was also observed that the time-latitude section of zonally averaged OLR and TMI derived cloud liquid water data clearly depict the propagation of convection and cloud from the equator to the north at the rate of 0.75° to 1° latitude per day which corroborates well with the rate of propagation derived from the phase lag obtained between the processes occurring at the equatorial Indian Ocean and rainfall recorded at the designated land segments. The results are in good agreement with the observations made by earlier investigators.  相似文献   

Modelling spatial variation of fluoride pollutant using geospatial approach in the surrounding environment of an aluminium industries     

Prem Chandra Pandey  Pavan Kumar  Vandana Tomar  Meenu Rani  Swati Katiyar  Mahendra Singh Nathawat 《Environmental Earth Sciences》2015,74(12):7801-7812

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Modified Chaplygin gas inspired inflationary model in braneworld scenario     

Abdul Jawad  Shamaila Rani  Sidra Mohsaneen 《Astrophysics and Space Science》2016,361(5):158

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Chaplygin gas inspired scalar fields inflation via well-known potentials     

Abdul Jawad  Sadaf Butt  Shamaila Rani 《Astrophysics and Space Science》2016,361(8):258

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