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Geostatistical and Geospatial Approaches for the Characterization of Natural Resources in the Environment : Challenges, Processes and Strategies
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www.capital-publishing.com
Geostatistical and Geospatial Approaches for the Characterization of Natural Resources
CAPITAL PUBLISHING COMPANY
Edited by N. Janardhana Raju
It is the perspective of these proceedings of IAMG2014 conference in New Delhi to explore the current state-of-the-art development and to apply geostatistical and geospatial based technologies for the assessment and management of natural resource exploration, environmental pollution, hazards and natural disaster research in modern science and technology. The proceedings cover mathematical geosciences and geostatistics, environmental geochemistry and pollution, tectonic activity and natural disaster, modeling and simulation, remote sensing and geoinformatics, and meteorology and climate change.
in the Environment: Challenges, Processes and Strategies
Application of mathematics play a key role in the lithosphere, hydrosphere, biosphere, cryosphere and atmospheric climate change causing natural disasters influencing fundamental aspects of lifesupporting systems and other geological processes affecting 'Planet Earth'. Due to an increase in the complexity of the problems faced by the geoscientists, a common effort is required to establish innovative conceptual and numerical models to develop new paradigms. The transformation from descriptive stage to a more quantitative stage involves qualitative interpretations (i.e. conceptual models) complemented with quantitative interpretations (i.e. numerical models, fast dynamic geologic models, deterministic and stochastic models).
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Geostatistical and Geospatial Approaches………………Challenges, Processes & Strategies, N.J. Raju (ed), © 2014, Capital Publishing Company, ISBN 978-93-81891-25-4
Geothermobarometry and Barrovian Metamorphism of DarjeelingMangpu Region, Eastern Himalaya Suparna Tewari* and Divya Prakash Centre of Advanced Study in Geology, Banaras Hindu University, Varanasi, India (*
[email protected])
Abstract: Along the Darjeeling–Mangpu region, polyphase deformation and barrovian metamorphism has been delineated in relation to the Main Central Thrust (MCT). The different parageneses of pelitic rocks containing chlorite, muscovite, biotite, garnet, staurolite, kyanite, sillimanite, k-feldspar and plagioclase show various texture resulting by the continuous and discontinuous reactions in the different zones. From the Microprobe data of the coexisting minerals show that XMg varies in order garnetgarnet, and XMn decreases in the order: garnet>staurolite> chlorite>biotite. The garnets do not reveal any prograde compositional changes. The X Mg of garnets decreases with an increase in XMn in garnet and increases with rise in Ca/Mn ratio of garnet. Weak zoning in the garnet from the zone C from the sample collected in the vicinity of the staurolite-biotiteisograd has been attributed to the Fe-Mg reaction. On the other hand, the garnets from the zones D and E are characterized by normal growth zoning with ball- shaped Mn and Ca profiles with Mn and Ca decreasing, and Fe, Mg and X Mg increasing from the core towards the periphery. However, near the rim the pattern of zoning is reverse of the growth zoning, i.e. increase in Mn and decrease of XMg and Mg. The normal growth zoning pattern of garnet has been attributed to continuous Fe-MgMn reaction.
4 GEOTHERMOBAROMETRY AND CONCLUSION The metamorphic conditions estimated through the different models of geothermometry and geobarometry and experimentally determined equilibria suggest pressures between 4.6-5 kbar for zone B, 5.5-6 kbar for zone C, 5.5-6.5 kbar for zone D and 7-7.5 for zone E and temperature between 450-550⁰C for zone A, 540-580⁰C for zone B, 580-600⁰C for zone C, 660-700⁰C for zone D and 680-780⁰C for zone E. The reverse metamorphic zoning pattern, with successive higher rocks lying at greater elevation and structural level, has been attributed to migration of metamorphic front due to abnormally high heat flow in the regions of the MCT in the Central Crystalline Zone of Himalaya where the rocks of Daling-Darjeeling group were metamorphosed, prior to their transportation by thrusting to the present position in the Lower Himalaya.
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Geothermobarometry and Barrovian Metamorphism….Eastern Himalaya
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