A techno-economic model for optimum regeneration of surface mined land     

Manas K. Mukhopadhyay  Indra N. Sinha 《Environmental Geology》2006,50(5):669-676

The recent global scenario in the mineral sector may be characterized by rising competitiveness, increasing production costs and a slump in market price. This has pushed the mineral sector in general and that in the developing countries in particular to a situation where the industry has a limited capacity to sustain unproductive costs. This, more often than not, results in a situation where the industry fails to ensure environmental safeguards during and after mineral extraction. The situation is conspicuous in the Indian coal mining industry where more than 73% production comes from surface operations. India has an ambitious power augmentation projection for the coming 10 years. A phenomenal increase in coal production is proposed from the power grade coalfields in India. One of the most likely fall-outs of land degradation due to mining in these areas would be significant reduction of agricultural and other important land-uses. Currently, backfilling costs are perceived as prohibitive and abandonment of land is the easy way out. This study attempts to provide mine planners with a mathematical model that distributes generated overburden at defined disposal options while ensuring maximization of backfilled land area at minimum direct and economic costs. Optimization has been accomplished by linear programming (LP) for optimum distribution of each year’s generated overburden. Previous year’s disposal quantity outputs are processed as one set of the inputs to the LP model for generation of current year’s disposal output. From various geo-mining inputs, site constants of the LP constraints are calculated. Arrived value of economic vectors, which guide the programming statement, decides the optimal overburden distribution in defined options. The case example (with model test run) indicates that overburden distribution is significantly sensitive to coal seam gradient. The model has universal applicability to cyclic system (shovel–dumper combination) of opencast mining of stratified deposits.  相似文献   

Prediction of tropical systems over Indian region using mesoscale model     

S. S. Vaidya  P. Mukhopadhyay  D. K. Trivedi  J. Sanjay  S. S. Singh 《Meteorology and Atmospheric Physics》2004,86(1-2):63-72

Summary The Advanced Regional Prediction System (ARPS) model developed at Center for Analysis and Prediction of Storms at Oklahoma State University, USA is used for simulation of monsoon depression and tropical cyclone over Indian region. The radiosonde data are included in the initial analyses and subsequently; the simulations are performed with 50km and 25km grid resolutions. Two sets of forecast experiments produced by two types of analyses (with radiosonde and without radiosonde data) are compared. It is found that predicted mean sea-level pressure of the depression becomes closer to mean sea level pressure reported in Indian Daily Weather Reports when initialized with analyses containing radiosonde data. The precipitation forecast also is improved when initialized with the analyses containing radiosonde data. The simulation of tropical cyclone with 25km grid resolution is able to simulate some subsynoptic scale features of the system.  相似文献   

Deformation and stresses in non-homogeneous earth models with a rigid core     

Mukhopadhyay  A. 《Pure and Applied Geophysics》1974,112(2):506-511

Summary Small-strain theory has been applied to find out the deformation and stresses in the interior of the earth considered as a self-gravitating, non-homogeneous, isotropic sphere of heterogeneous density distribution. Stresses have been compared at different layers due to different density distributions.  相似文献   

Transfer of solar angular momentum by inertial induction     

Amitabha Ghosh 《Earth, Moon, and Planets》1988,42(1):69-75

Transfer of angular momentum from the Sun to the planetary system has been found to be inevitable in all evolutionary models for the origin of the solar system. In cold theories it has been proposed to be achieved through friction whereas electromagnetic forces are considered to be the agent for this transfer in hot theories. In the present paper it has been shown that the required order of magnitude of angular momentum can be transferred by another mechanism based on the principle of inertial induction. In the previous theories most of the transfer had been assumed to have taken place during the pre-Main-Sequence period whereas in this proposed theory most of the transfer takes place during the Main-Sequence period of the Sun. The paper does not intend to go into the details of planet formation and the evolutionary process but confines itself only to the problem of angular momentum transfer.  相似文献   

Implementing a Spatial Model to Derive Potential Fishing Zones in the Northern Bay of Bengal Lying Adjacent to West Bengal Coast,India     

Sandip Giri  Sudip Manna  Abhra Chanda  Avirup Chowdhury  Anirban Mukhopadhyay  Sarbari Chakraborty  Sugata Hazra 《Journal of the Indian Society of Remote Sensing》2016,44(1):59-66

Potential fishing zones (PFZ’s) are those regions where the fishes aggregate due to an abundance of food and they are demarcated by tracing those regions in the ocean, where a sharp sea surface temperature (SST) gradient along with optimal chlorophyll (Chl) concentration co-exists at a given time. In this regard, Indian National Centre for Ocean Information Services (INCOIS) disseminates the daily PFZ forecasts in Bay of Bengal and Arabian Sea to aid the fishermen community. The present study is an endeavor to develop a local spatial model derived Potential Fishing Zone (PFZ) in the northern Bay of Bengal (nBoB) lying adjacent to the West Bengal coast. Satellite derived SST and chlorophyll data obtained for two consecutive winter seasons of 2010–11 and 2011–12 were used to generate line density (LD) raster. Shapefiles of INCOIS predicted PFZs were overlaid on these LD raster to extract the corresponding pixel values. Histogram ranges of the extracted pixels were fixed and same values lying in the LD raster of both SST and chlorophyll other than INCOIS PFZs were detected by a spatial model in ERDAS. The PFZs thus derived were validated against the ground fish catch data and it was observed that good fish catch was seen in the model derived additional PFZs also. The catch per unit effort (CPUE) values was found to be very close to that of the CPUE value of PFZ advisories of INCOIS. However, the CPUE in the non PFZ areas were significantly lower than the former two categories.  相似文献   

Magmatism in western Cuddapahs: The mafic sills and lava flows of Vempalle and Tadpatri formations     

Kasturi Chakraborty  P. K. Mukhopadhyay  Praveer Pankaj 《Journal of the Geological Society of India》2016,87(6):631-660

The western part of Cuddapah basin has been considered as a foreland to the fold-thrust belt represented by eastern Nallamalais and Nellore schist belt. The igneous activities, in the form of lava flows and sills, in western Cuddapahs have been a subject of controversy since tectonogenetic models ranging from a mantle plume to lithospheric extension have been suggested. The present work covers a detailed study of the mafic sills and lava flows of Vempalle and Tadpatri formations in western Cuddapahs, which earlier workers have also noted. A detailed field and laboratory work in this study brings out, for the first time, five distinct petrographic and geochemical varieties of sills. Geochemical studies also suggest that the different sill types have originated from varying degrees of partial melting of a metasomatized subcrustal lithospheric mantle, the metasomatism of source being attributed to older Archaean convergent settings/greenstone belts that the basin unconformably overlies. The possible contribution of any small plume is only heating and doming of overlying mantle that induced incipient crustal rifting. Our geochemical studies on the lava flows of Vempalle Formation also suggest that the magma was derived from small degree of partial melting of spinel-garnet peridotite mantle in a rift setting.  相似文献   

Ancient Surfaces Associated with Gondwana Sequences of Peninsular India     

A.B. Dutt  Avijith Mukhopadhyay 《Gondwana Research》1999,2(4):663

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The Neoproterozoic Cratonic Successions of Peninsular India     

Asru K. Chaudhuri  Joydip Mukhopadhyay  Sarbani Patranabis Deb  S.K. Chanda   《Gondwana Research》1999,2(2):213

The Peninsular India hosts extensive record of Mesoproterozoic, and Neoproterozoic successions in several mobile belts, and cratonic basins. The successions provide excellent opportunities for chronostratigraphic classification, in tune with the chronometric classification adopted by IUGS for inter-regional correlation on a global scale. Major tectono-thermal events at 1000–950 Ma in the mobile belts, correlatable with the Grenville orogeny may be considered as the datum for Meso-Neoproterozoic classification in India. Principles of chronostratigraphic classification, however, can not be applied yet to the cratonic successions of India because of inadequate radiometric data, paucity of biostratigraphic studies, and lack of regionally correlatable stratigraphic or palaeoclimatic datum. The kimberlite magmatism which affected the Peninsular India on a continental scale at about 1100 Ma, holds the key to the identification of Neoproterozoic successions of the cratonic basins. Thus, the stratigraphically confined diamond-bearing conglomerates and/or the tuffs associated with kimberlites, may be considered as the datum to define the base of the Neoproterozoic, fixed at about 1000 Ma. Accordingly, the Rewa, and Bhander Groups in the Vindhyan basin, the Kurnool Group in the Cuddapah basin, the Jagdalpur Formation in the Indravati basin, and the Sullavai Group in the Pranhita-Godavari basin are taken to represent the Neoproterozoic successions in the Peninsular India. The Chattisgarh Group in the central India, the lower part of the Marwar Supergroup in western Rajasthan, the Badami Group in the Kaladgi basin, and the Bhima Group are the other “possible Neoproterozoics” in the Peninsula.The closing phase of the Mesoproterozoic in all these basins are characterised by stable shelf lithologic associations attesting to high crustal stability. The Neoproterozoic basins, by contrast, mark a new phase of rifting, and extension, and the basin fills exhibit signatures of initial instability which evolved with time into a more stable platformal condition. A major episode of sea level rise has been recorded in most of the basins. The riftogenic origin, and evolution of the basins are comparable with the history of Neoproterozoic basins of Australia though there is no unequivocal record of glaciation in the Indian formations.  相似文献   

A balanced cross section across the Himalayan foreland belt, the Punjab and Himachal foothills: A reinterpretation of structural styles and evolution     

Dilip K. Mukhopadhyay  Premanand Mishra 《Journal of Earth System Science》1999,108(3):189-205

The Siwaliks in the foothills of the Himalayas, containing molasse sediments derived from the rising mountain front, represent a foreland fold-thrust belt which was deformed during the continued northward convergence of the Indian plate following the continent-continent collision. In this contribution we present balanced and restored cross sections along a line from Adampur through Jawalamukhi to Palampur in the foothills of the Punjab and Himachal Himalayas using published surface/subsurface data. The cross section incorporates all the rock units of the Sub-Himalaya Zone as well as that of the northern Lesser Himalaya Zone. The structural geometry of the fold-thrust belt in this section is largely controlled by three buried thrusts within the Sundernagar Formation of the Lesser Himalaya Zone. Two of these buried thrusts splay from the basal detachment and delineate a buried horse. Three thrusts towards foreland, including the Main Frontal Thrust (inferred to be a blind thrust in this sector), splay from these buried thrusts. In the hinterland, an anticlinal fault-bend fold was breached by a sequence of break-back thrusts, one of which is the Main Boundary Thrust. A foreland propagating thrust system is inadequate to explain the evolution of the fold-thrust-belt in this section. We show that a “synchronous thrusting” model in whichin-sequence initiation of thrusts at depth combined with continued motion on all the thrusts leading toout-of-sequence imbrication at the upper structural levels better explains the evolution of the fold-thrust belt in the Jawalamukhi section. The estimated shortening between the two chosen pin lines is about 36% (about 72 km).  相似文献   

Finite element analysis of ship structures using a new stiffened plate element   总被引：2，自引：0，他引：2  

Y. V. Satish Kumar  M. Mukhopadhyay   《Applied Ocean Research》2000,22(6):361-374

A new stiffened plate element is developed for the three-dimensional finite element analysis of ship structures. The plate element can accommodate any number of arbitrarily oriented stiffeners and obviates the use of mesh lines along the stiffeners. The new element provides a very economic global analysis of the complete ship structure with fewer elements and without any loss of accuracy. The global analysis of a rectangular box shaped vessel is carried out with the present element and compared with the general-purpose finite element software NISA. An Offshore Tug/Supply Vessel is analysed for crest at perpendiculars.  相似文献