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11.
Spatial modeling using high resolution image for future shoreline prediction along Junput Coast,West Bengal,India 总被引:1,自引:0,他引:1
National policies and legal decisions are very much dependent on the position of the shoreline. Shoreline change rates are frequently employed to summarize historical shoreline movements. This also helps to predict the future position of the shoreline based on the perceived historical trends. In this regard, the future shoreline positions at both the long-term, that is 2050, and short-term, that is 2015, time interval was predicted using the End Point Rate (EPR) model along the Junput Coast of West Bengal, India. The whole project work was divided into five parts. The first part showed the detection of shoreline from satellite data like IRS LISS Ⅳ and Landsat 7 ETM+ and from the Survey of India Toposheet. The second part gave the glimpse of the dynamic segmentation of the shoreline to get the dynamically segmented nodal points along the shoreline. Shoreline prediction for the years 2015 and 2050 using End Point Rate (EPR) model was done in the third part. In the fourth part, Coastal Terrain Model (CTM) was prepared, and the digital shoreline estimated. The model result was validated and accuracy assessed with respect to the GPS data collected from the field at the fifth stage. Finally at the end of the present work, limitations of the project and the future scope of the work was sited. 相似文献
12.
Saibal Gupta Jagatbikas Nanda Sumit Kumar Mukherjee Manasij Santra 《Gondwana Research》2005,8(3):403-419
Linear domains of deformed alkaline rocks and carbonatites have recently been identified as representing sites of ancient suture zones. In peninsular India, the western margin of the Proterozoic Eastern Ghats Belt (EGB) is characterized by a series of alkaline plutons that are aligned close to the contact with the Archaean Craton. Most of the complexes were deformed and metamorphosed during a subsequent orogenic event. Unlike other plutons in the belt, the alkaline complex at Koraput reportedly escaped deformation and granulite facies metamorphism forming an anomalous entity within the zone. Multiply-deformed country rocks hosting this complex underwent syn-D1CR granulite facies metamorphism followed by D2CR thrusting, with pervasive shearing along a NE-SW trending foliation. A second granulite facies event followed localized D3CR shearing. Within the Koraput Complex, strain partitioning was responsible for preserving igneous textures in the gabbroic core, but aligned magmatic amphibole needles and plagioclase laths occasionally define a S1AC fabric. Along the margins, S1AC is rotated parallel to a NE-trending, east-dipping S2AC fabric in the gabbro, fringing syenodiorite and nepheline syenite bands. Locally, D3AC shearing follows D2AC deformation; S2AC and S3AC parallel S2CR and S3CR in the country rocks. High-grade metamorphism represented by recrystallization of amphibole and plagioclase, and breakdown of amphibole and biotite to garnet, pyroxene and K-feldspar in the complex follows D3AC. Unlike earlier reports, therefore, the Koraput body is also deformed and metamorphosed. The aligned alkaline complexes in the EGB probably represent deformed alkaline rocks and carbonatites formed by rifting related to an earlier episode of continental break-up that were deformed during subsequent juxtaposition of the EGB with the Archaean Craton. This supports the contention that the western margin of the EGB and its contact with the Archaean Craton is a suture zone related to the Indo-Antarctica collision event. 相似文献
13.
Priyabrata Das Kaushik Das Partha Pratim Chakraborty S Balakrishnan 《Journal of Earth System Science》2011,120(2):223-236
Besides offering significant clues towards tracking the geochemical evolution of the mantle and architectural reconstruction
of different ‘supercontinent’, geochronological and geochemical appraisal of igneous inputs are also important to bracket
the depositional time frame of any lithopackage, particularly, the unfossiliferous sedimentary successions. The present study
deals with diabasic intrusive within Mesoproterozoic Saraipalli Formation, which is an argillaceous constituent present at
the basal part of nearly 400 m thick four-tiered unmetamorphosed but deformed sedimentary succession of Singhora Group, Chhattisgarh
Supergroup, central India. The SE–NW trending intrusive comprises mainly of plagioclase and augite together with minor orthopyroxene,
biotite and opaque minerals. Though some plagioclase laths are partially sericitized, the ophitic-to-subophitic texture of
the rock is well preserved. Major and trace element geochemical data indicate that this intrusive is basalt-to-basaltic andesite
in character and of subalkaline basalt affinity. Multi-element plot shows overall LILE-enrichment and enrichment of Pb and
slight depletion of Nb and P, coupled with moderate La/Nb and Th/Nb ratios. Zr, Y and Nb ternary diagrams plot in the fields
of within plate basalt. Selected HFSE ratios indicate a non-plume source with crustal assimilation/sediment mixing. Sm–Nd
and Rb–Sr isotope data show that the intrusive has Srinitial and Ndinitial of 0.709377–0.706672 and 0.510919–0.510815, respectively. Positive ε
t
Nd [t = 1420 Ma] values (+0.3 to + 2.3) indicate depleted isotopic nature of their protolith. The calculated T
DM age is 1.7–1.9 Ga. The mineral-whole rock isochron data (Sm–Nd systematics) of the intrusive implies an emplacement age of
ca. 1420 Ma. Considering synchronous terrain boundary shear zone development in Bastar craton on the southeastern part of
the Singhora basin, mafic magmatism in Eastern Ghats and large-scale basic intrusion in Sausar mobile belt, a major tectono-thermal
event around 1400 Ma is surmised that affected eastern Indian craton. Moreover, geochronology of a bedded porcellanite unit
(ca. 1500 Ma) at the base and a discordant basic intrusive (ca. 1420 Ma) allowed a unique opportunity to qualitatively offer
an upper bound of time bracket for the deposition of Saraipalli Formation, i.e., ∼80 Ma. 相似文献
14.
Indrani Choudhury M. Chakraborty S. C. Santra J. S. Parihar 《Journal of the Indian Society of Remote Sensing》2006,34(1):23-37
Information on various agricultural resource parameters at various levels is essential for proper management and efficient
resource allocation for sustainable agricultural development. Limitations in ground-based method have encouraged the use of
satellite data coupled with geographical information system (GIS) in providing spatial as well as temporal information over
large and inaccessible areas. In the present study, an attempt has been made to generate raster maps using remote sensing
and GIS techniques to characterize the agroecosystem of South 24 Paraganas district of West Bengal, based on land utilization
indices. Information on multi-season landcover derived from the analysis of the multi-temporal RADARSAT-1 SAR and IRS-ID LISS
III data as well as other ancillary information in GIS environment are the basic inputs used in the study. The present analysis
shows that northern and northwestern parts are more diverse in terms of agricultural intensification as compared to the southern
and northeastern parts whereas the central parts show moderate density. In terms of carrying capacity, the high carrying capacity
has been observed in the southern to northeastern parts whereas the northwestern and central parts show moderate and northern
parts show low carrying capacity. Overall, the characterization of agroecosystem using land utilization indices can be identified
as major input to formulate a management plan for sustainable agriculture with concerns for the environment. 相似文献
15.
AbstractThe objective of this study is to measure the balance of water demand versus water resource availability in an interfluve of West Bengal, India to support water resource planning, particularly of inter-basin transfers. Surface water availability was modelled using the US Soil Conservation Service curve number (SCS-CN) approach, whilst groundwater availability was modelled based on water-level fluctuations and the rainfall infiltration method. Water use was modelled separately for the agricultural, industrial, and domestic sectors using a predominantly normative approach and water use to availability ratios calculated for different administrative areas within the interfluve. Overall, the approach suggested that the interfluve receives 327 × 106 m3 year-1 of excess water after satisfying these sectoral demands, but that the eastern part of the study area is in deficit. However, a sensitivity analysis carried on the approach to several assumptions in the model suggested changed circumstances would produce surplus/deficit ranging from ?215 × 106 to 435 × 106 m3 year-1 . The approach could have potential for localised water balance modelling in other Indian catchments.
Editor D. Koutsoyiannis; Associate editor D. Hughes 相似文献