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91.
92.
Rajat M. Thomas Saleem Zaroubi Benedetta Ciardi reas H. Pawlik Panagiotis Labropoulos Vibor Jeli Gianni Bernardi Michiel A. Brentjens A. G. de Bruyn Geraint J. A. Harker Leon V. E. Koopmans Garrelt Mellema V. N. Pandey Joop Schaye Sarod Yatawatta 《Monthly notices of the Royal Astronomical Society》2009,393(1):32-48
93.
Geraint Harker Saleem Zaroubi Gianni Bernardi Michiel A. Brentjens A. G. de Bruyn Benedetta Ciardi Vibor Jeli Leon V. E. Koopmans Panagiotis Labropoulos Garrelt Mellema ré Offringa V. N. Pandey Joop Schaye Rajat M. Thomas Sarod Yatawatta 《Monthly notices of the Royal Astronomical Society》2009,397(2):1138-1152
94.
Santosh Kumar S. Raju Manjari Pathak Abhishek Pandey 《Journal of the Geological Society of India》2010,75(3):539-548
Late Archaean to Palaeoproterozoic felsic magmatic lithounits exposed in the central part of the Bundelkhand massif have been
mapped and their redox series (magnetite vs ilmenite series) evaluated based on magnetic susceptibility (MS) data. The central
part of Bundelkhand massif comprises of multiple felsic magmatic pulses (∼2600–2200 Ma), commonly represented by coarse grained
granite (CGG-grey granite, CPG-pink granite), medium grained pink granite (MPG), fine grained pink granite (FPG), grey and
pink rhyolites and granite porphyry (GP). However, the pink colour of these felsic rocks is the result of hydrothermal fluid-flushing
leading to potassic alteration of grey granites. MS values of CGG vary from 0.058 to 14.75×10−3 SI with an average of 6.35×10−3 SI, which mostly represent oxidized type, magnetite series (73%) granites involving infracrustal (igneous) source materials.
CPG (av. MS=3.95×10−3 SI) is indeed a pink variety of CGG, the original oxidizing nature of which must have been similar to the bulk of CGG, but
has been moderately to strongly reduced because of distinctly more porphyritic nature together with partial assimilation of
metapelitic (supracrustal) materials, surmicaceous enclaves, carbonaceous material included in the source materials, and to
some extent, induced by hydrothermal and later deformational processes. MPG (av. MS= 1.15×10−3 SI) as lensoidal stock-like bodies intrudes the CPG and represent both magnetite series (18%) and ilmenite series (82%) granites,
which are probably formed by heterogeneous (mixed) source rocks. GP (av. MS=6.26×10−3 SI) occur as dykes (mostly trending NE-SW) intrudes the MPG, CPG and migmatites and bears the nature similar to oxidized
type, magnetite series granite. FPG (av. MS= 0.666×10−3 SI) trending NE-SW occur as lensoid bodies including a large outcrop, is intrusive into both CPG and MPG, and is moderately
to very strongly reduced type, ilmenite series granites, which may be derived by the melting of metapelitic crustal sources.
FPG hosting microgranular (mafic magmatic) enclaves commonly exhibit high MS values (7.31–10.22×10−3 SI), which appear induced by the mixing and mingling of interacting felsic and mafic magmas prevailed in an open system.
Grey (av. MS=10.30×10−3 SI) and pink (av. MS=6.72×10−3 SI) rhyolites represent oxidized type, magnetite series granites, which may have been derived from infracrustal (magmatic)
protoliths. Granite series evaluation of felsic magmatic rocks of central part of Bundelkhand massif strongly suggests their
varied redox conditions (differential oxygen fugacity) mostly intrinsic to magma source regions and partially modified by
hydrothermal and tectonic processes acting upon them. 相似文献
95.
96.
The pre‐calibrated and validated physically based watershed model, water erosion prediction project (WEPP) was used as a modelling tool for the identification of critical watersheds and evaluation of best management practices for a small hilly watershed (Karso) of India. The land use/cover of the study area was generated using IRS‐1C LISS‐III (linear imaging self scanner) satellite data. The watershed and sub‐watershed boundaries, drainage, slope and soil map of the study area were generated using ARC/INFO geographic information system (GIS). The WEPP model was finally applied to the Karso watershed which lies within Damodar Barakar catchment of India to identify the critical sub‐watersheds on the basis of their simulated average annual sediment yields. Priorities were fixed on the basis of ranks assigned to each critical sub‐watershed based on the susceptibility to erosion. The sub‐watershed having the highest sediment yield was assigned a priority number 1, the next highest value was assigned a priority number 2, and so on. Subsequently, the model was used for evaluating the effectiveness of best management practices (crop and tillage) for conservation of soil for all the sub‐watersheds. On the basis of this study, it is realized that cash crops like soyabean should be encouraged in the upland portion of the sub‐watersheds, and the existing tillage practice (country plough/mould board plough) may be replaced by a field cultivation system for conservation of soil and water in the sub‐watersheds. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
97.
Atmospheric temperature profiles have been derived using 53·74 GHz, 54·96 GHz and 57·95 GHz channels data from the Microwave Sounding Unit onboard TIROS-N. For this purpose regression coefficients have been derived using MONEX-79 radiosonde data during the period May to July 1979. The temperature profiles derived at a few selected places were closer to radiosonde profiles than the profiles derived using standard regression coefficients for the tropical region supplied by NOAA. 相似文献
98.
Om Prakash Pandey 《Journal of Volcanology and Geothermal Research》1981,10(4):309-316
Large variations in terrestrial heat flow from 21 to 209 mW/m2 have been observed over the North Island, New Zealand. This is generally in good agreement with the pattern of existing geological and geophysical observations. A high heat flow zone with a value of 92 ±3 mW/m2, which corresponds to melting temperatures near the base of the crust, is delineated in the northern part of the Taranaki Basin. In the rest of the island, heat flow appears to be low to normal, but some isolated high values are also found. Observed results are interpreted in terms of crust and mantle structure in a region of plate subduction. 相似文献
99.
100.
Janardan G. Negi Pramode K. Panda Om Prakash Pandey 《Earth and Planetary Science Letters》1974,21(2):143-148
Correlation coefficients are calculated from the available geothermic data for the sedimentary basins of India to reveal some significant association between: (1) heat flow and thermal conductivity, (2) heat flow and geothermal gradient, (3) geothermal gradient and thermal conductivity, and (4) heat flow and related crustal thickness. The observed negative correlationship between heat flow and thermal conductivity for all Indian sedimentary basins suggests corresponding changes in crustal thickness. 相似文献