Estimation of specific yields of individual litho-units in a terrain with multiple litho-units: A water balance approach   总被引：1，自引：0，他引：1  

Ranjan Kumar Ray  Arunangshu Mukherjee  Rumi Mukherjee 《Journal of the Geological Society of India》2014,84(2):221-226

In a terrain with more than one litho-unit, the traditional water balance approach provides a single spatially averaged specific yield. A methodology is proposed here, which can be applied to estimate specific yields of individual litho-units in such terrains. This approach is demonstrated here considering two watersheds, which are covered partly by limestone and partly by sandstone. Watershed wise specific yields were estimated using a traditional water balance method. The specific yields thus obtained are the volume-weighted averages of the specific yields of the individual litho-units in the watersheds. Based on the volumes of aquifers desaturated and the watershed wise specific yield values, a set of two linear equations in two variables was formulated. These linear equations were solved to get the specific yields of the individual litho-units. Specific yields of sandstone (Chandarpur Group) and limestone (Charmuria Formation) units in the study area were thus estimated to be 0.004 and 0.037 respectively.  相似文献   

Land Cover Mapping for Namdapha National Park (Arunachal Pradesh), India Using Harmonized Land Cover Legends     

Mahendra S. Lodhi  Prasanna K. Samal  Shivaji Chaudhry  L. M. S. Palni  P. P. Dhyani 《Journal of the Indian Society of Remote Sensing》2014,42(2):461-467

Since last few decades RS-GIS is playing vital role in studying and mapping spatiotemporal responses of land cover, however, as a matter of fact, the mapping outputs largely depend on the expert's/user's preferences because location specific and people specific land cover classification systems are adopted autonomously for image classification in GIS. This may actually lead to an ambiguous definition of a particular land cover type when such different maps are compared at global level. In 1993, FAO and UNEP started efforts for development of a software tool know as LCCS which is a comprehensive standardized tool capable of providing land cover characterization to all possible land cover types in the world regardless of spatial relevance, mapping scale, data collection method etc. Adding to the global efforts of land cover legend harmonization and mapping, this study presents development of harmonized land cover legends for Namdapha National Park located in north-eastern Indian Himalayan region using LCCS and subsequent mapping. The potential of Remote Sensing (RS) and Geographical Information Systems (GIS) in forest/land cover mapping is very well recognized. Therefore, adopting the developed harmonized legends for the study area, land cover mapping was done using RS-GIS approach.  相似文献   

Exact solutions in (2+1)-dimensional anti-de Sitter space-time admitting a linear or non-linear equation of state     

Ayan Banerjee  Farook Rahaman  Kanti Jotania  Ranjan Sharma  Mosiur Rahaman 《Astrophysics and Space Science》2015,355(2):353-359

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Testing isotropy of cosmic microwave background radiation     

Pramoda Kumar Samal  Rajib Saha  Pankaj Jain  John P. Ralston 《Monthly notices of the Royal Astronomical Society》2008,385(4):1718-1728

We introduce new symmetry-based methods to test for isotropy in cosmic microwave background (CMB) radiation. Each angular multipole is factored into unique products of power eigenvectors, related multipoles and singular values that provide two new rotationally invariant measures mode by mode. The power entropy and directional entropy are new tests of randomness that are independent of the usual CMB power. Simulated Galactic plane contamination is readily identified. The ILC– WMAP data maps show seven axes well aligned with one another and the direction Virgo. Parameter free statistics find 12 independent cases of extraordinary axial alignment, low power entropy, or both having 5 per cent probability or lower in an isotropic distribution. Isotropy of the ILC maps is ruled out to confidence levels of better than 99.9 per cent, whether or not coincidences with other puzzles coming from the Virgo axis are included. Our work shows that anisotropy is not confined to the low l region, but extends over a much larger l range.  相似文献   

GIS-based vulnerability mapping of the coastal stretch from Puri to Konark in Odisha using analytical hierarchy process     

Behera  Rashmisikha  Kar  Abhipsa  Das  Manas Ranjan  Panda  Prachi Prava 《Natural Hazards》2019,96(2):731-751

Natural Hazards - The 485-km-long coastline of Odisha, a state in the northeastern part of the Indian peninsula, is potentially vulnerable to several disaster events that take place frequently. In...  相似文献   

Integration of Sparse Geologic Information in Gold Targeting Using Logistic Regression Analysis in the Hutti–Maski Schist Belt,Raichur, Karnataka,India—A Case Study     

Sahoo  Nihar Ranjan  Pandalai  Hari Shankar 《Natural Resources Research》1999,8(3):233-250

Logistic regression has been used in the study to integrate indicator patterns for estimation of the probability of occurrence of gold deposits in a part of the auriferous Archaean Hutti–Maski schist belt. Data used consist of categorical and continuous variables obtained from a coded lineament map and geochemical anomaly maps of the pathfinder elements of gold in soil and groundwater. Main effects and interactions of the variables studied were used in formulating the logistic regression model. Regression models using lineament-proximity data, combined with soil and groundwater geochemical anomalies were tested on parts of the schist belt with data not used in estimation of model parameters. Predicted probabilities greater than 0.9 identified known deposit locations in the area.  相似文献   

Axial behavior of tapered piles using cavity expansion theory     

Singh  Sonal  Patra  Nihar Ranjan 《Acta Geotechnica》2020,15(6):1619-1636

Acta Geotechnica - This paper presents a procedure for evaluating the load–displacement behavior of tapered piles under static axial compressive loads. The response of tapered piles under...  相似文献   

Probabilistic seismic hazard assessment for some parts of the Indo-Gangetic plains,India     

Keshri  Chhotu Kumar  Mohanty  William Kumar  Ranjan  Pratul 《Natural Hazards》2020,103(1):815-843

Natural Hazards - Indo-Gangetic plains are seismically most vulnerable due to the proximity of adjacent great Himalayan earthquakes and thick alluvium deposits of the Ganga River system. As the...  相似文献   

Calibration and validation of a general infiltration model     

Surendra Kumar Mishra  Shashi Ranjan Kumar  Vijay P. Singh 《水文研究》1999,13(11):1691-1718

A general infiltration model proposed by Singh and Yu (1990) was calibrated and validated using a split sampling approach for 191 sets of infiltration data observed in the states of Minnesota and Georgia in the USA. Of the five model parameters, f_c (the final infiltration rate), S_o (the available storage space) and exponent ‘n’ were found to be more predictable than the other two parameters: m (exponent) and a (proportionality factor). A critical examination of the general model revealed that it is related to the Soil Conservation Service (1956) curve number (SCS‐CN) method and its parameter S_o is equivalent to the potential maximum retention of the SCS‐CN method and is, in turn, found to be a function of soil sorptivity and hydraulic conductivity. The general model was found to describe infiltration rate with time varying curve number. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   

Comparative analysis of contributing parameters for rainfall-triggered landslides in the Lesser Himalaya of Nepal   总被引：6，自引：0，他引：6  

Ranjan Kumar Dahal  Shuichi Hasegawa  Minoru Yamanaka  Santosh Dhakal  Netra Prakash Bhandary  Ryuichi Yatabe 《Environmental Geology》2009,58(3):567-586

In the Himalaya, people live in widely spread settlements and suffer more from landslides than from any other type of natural disaster. The intense summer monsoons are the main factor in triggering landslides. However, the relations between landslides and slope hydrology have not been a focal topic in Himalayan landslide research. This paper deals with the contributing parameters for the rainfall-triggered landslides which occurred during an extreme monsoon rainfall event on 23 July 2002, in the south-western hills of Kathmandu valley, in the Lesser Himalaya, Nepal. Parameters such as bedrock geology, geomorphology, geotechnical properties of soil, and clay mineralogy are described in this paper. Landslide modeling was performed in SEEP/W and SLOPE/W to understand the relationship of pore water pressure variations in soil layers and to determine the spatial variation of landslide occurrence. Soil characteristics, low angle of internal friction of fines in soil, medium range of soil permeability, presence of clay minerals in soil, bedrock hydrogeology, and human intervention were found to be the main contributing parameters for slope failures in the region.  相似文献