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T. C. Devaraju R. P. Viljoen R. H. Sawkar T. L. Sudhakara 《Journal of the Geological Society of India》2011,78(6):601-602
News and Notes
Workshop on Precambrian Tectonics and Related Mineralization in South India — P. Krishnamurthy (Email: gsocind@gmail.com) 相似文献2.
News and Notes
Penrose Conference — 2011 on Deformation Localization in Rocks: New Advances — Manish A. Mamtani (IIT, Kharagpur; Email: mamtani@gg.iitkgp.ernet.in) 相似文献3.
Sisir K. Mondal 《Journal of the Geological Society of India》2011,78(4):390-391
News and Notes
National Seminar on Orissa’s Mineral, Environment and Geosciences Assessment — 2011 (OMEGA-2011) and Golden Jubilee of Geological Survey of India, Orissa — M. Mohanty and K. C. Sahoo (Email: manoranjanmoha@gmail.com) 相似文献4.
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Thea Vogt 《Comptes Rendus Geoscience》2012,344(10):535-537
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Richard Mbatu 《GeoJournal》2010,75(5):443-458
This paper characterizes changes in land use and forest cover in southern Cameroon. In doing so, we use remotely sensed data
to define the rates and area of forest loss and cover change in two reference areas over a period of 16 years (from 1984 to
2000)—the Buea-Limbe area in the southwest province and the Bertoua area in the east province. We relate socio-economic data
of these study areas with results from the empirical spatial analysis to explain causes of deforestation. A second set of
explanations, which we call the theoretical perspective, attributes deforestation in southern Cameroon to the intricacies
of modernization, world-systems, and neo-Malthusian theories. 相似文献
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S. Ladage 《Journal of the Geological Society of India》2011,78(6):603-604
News and Notes
International Earth Science Olympiad — 2011: A Report — R. Shankar (National Coordinator, Earth Science Olympiad; Email: rshankar_1@yahoo.com) 相似文献12.
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Experimental studies on the two solid solutions franckeite s.s. and cylindrite s.s. yielded among others thePb-free endmembers of franckeite and cylindrite respectively. In these endmembers the lead content of the twomineral phases are completely substituted by bivalent tin. A third phase, ottemannite s.s. with (Fe. Sb)-bearingcompositions, was further identified in the Pb-free 4-component system Fe-Sn-Sb-S. Pb-free franckeite andcylindrite could only be synthesized as homogeneous phases at high temperatures. The ottemannite s.s. was ob-tained at 600℃ but an extensive existing range was also confirmed at temperatures below 500℃. The phase relations were discussed in the pseudoternary subsystem SnS-SnS_2-FeSb_2S_4. The following se-quence of Pb-free phases and phase assemblages were observed under increasing Sn~(4+) content at 600℃:herzenhergite (SnS)+franckeite, franckeite, franckeite+cylindrite, cylindrite, cylindrite+(Fe, Sb)-ottemannite.(Fe, Sb)-ottemannite. (Fe. Sb)-ottemannite+berndtite (SnS_2). The assemblage cylindrite+berndtite was identi-fied in synthetic systems involving Pb. The phase Fe. Sb-ottemannite s.s. appears to be stable only under Pb-de-ficient and high sulfur fugacity conditions. 相似文献
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Elisabetta Rampone Giovanni B. Piccardo Albrecht W. Hofmann 《Contributions to Mineralogy and Petrology》2008,156(4):453-475
Spinel and plagioclase peridotites from the Mt.Maggiore (Corsica, France) ophiolitic massif record a composite asthenosphere–lithosphere
history of partial melting and subsequent multi-stage melt–rock interaction. Cpx-poor spinel lherzolites are consistent with
mantle residues after low-degree fractional melting (F = 5–10%). Opx + spinel symplectites at the rims of orthopyroxene porphyroclasts indicate post-melting lithospheric cooling
(T = 970–1,100°C); this was followed by formation of olivine embayments within pyroxene porphyroclasts by melt–rock interaction.
Enrichment in modal olivine (up to 85 wt%) at constant bulk Mg values, and variable absolute REE contents (at constant LREE/HREE)
indicate olivine precipitation and pyroxene dissolution during reactive porous melt flow. This stage occurred at spinel-facies
depths, after incorporation of the peridotites in the thermal lithosphere. Plagioclase-enriched peridotites show melt impregnation
microtextures, like opx + plag intergrowths replacing exsolved cpx porphyroclasts and interstitial gabbronoritic veinlets.
This second melt–rock interaction stage caused systematic chemical changes in clinopyroxene (e.g. Ti, REE, Zr, Y increase),
related to the concomitant effects of local melt–rock interaction at decreasing melt mass, and crystallization of small (<3%)
trapped melt fractions. LREE depletion in minerals of the gabbronoritic veinlets indicates that the impregnating melts were
more depleted than normal MORB. Preserved microtextural evidence of previous melt–rock interaction in the impregnated peridotites
suggests that they were progressively uplifted in response to lithosphere extension and thinning. Migrating melts were likely
produced by mantle upwelling and melting related to extension; they were modified from olivine-saturated to opx-saturated
compositions, and caused different styles of melt–rock interaction (reactive spinel harzburgites, vs. impregnated plagioclase
peridotites) depending on the lithospheric depths at which interaction occurred.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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《Proceedings of the Geologists' Association. Geologists' Association》2022,133(6):501-517
Loess was first identified in England as early as the mid-19th century, although these deposits were later mapped as ‘brickearth’ or ‘head-brickearth’ by the British Geological Survey. Much of this material was subsequently recognised and named as loess again by soil scientists, most notably by J.A. Catt. The early reports of loess were mostly located in southeast England, however, more recently loessic deposits have also been reported from the north of England, possibly in Scotland, and as far west as western Ireland. Catt also appreciated that these deposits are the western limits of a broad cover of loess stretching across Eurasia. Here, contrasting models for the possible origin, transport pathways and reworking of these deposits are presented. While some of these British deposits are primary in situ loess, a range of processes has likely affected many of them, including periglaciation, Holocene climatic, and human impacts. Luminescence dating has confirmed British loess to be primarily of late Pleistocene age, however, examples of older loess are also reviewed. Deposits in southeast England are the thickest and best expressed today, and these have yielded significant insight into both the mechanism of the hydroconsolidation (collapse) of loess and landscape evolution in northwest Europe during the Last Glacial Period. The thin and regional nature of British and Irish loess may make it an excellent material for studying loess formation, with advantages over the thicker deposits of typical loess of central Europe, where the impact of smaller scale landscape processes may be less obvious. 相似文献
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