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51.
Geology of Ore Deposits - Niobium minerals in zwitter and lithium–fluorine granite of the Verkhneurmiysky granitic massif in the Amur River region—fergusonite-(Y), euxenite-(Y),...  相似文献   
52.
Geology of Ore Deposits - The paper discusses the concepts of pegmatitic rocks, pegmatite and pegmatoid bodies, and classification of granitic pegmatites and their relationships with various types...  相似文献   
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Theoretical and Applied Climatology - In the last decades, anthropogenic drivers have significantly influenced the natural climate variability of Earth’s atmosphere. Climate change has become...  相似文献   
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The Groapa Vântului (Wind’s Dip) landslide, situated in the Buz?u Carpathians, on the right-hand slope of the Siriu Reservoir, occurred in April 2006, after the first local movements were signaled in September–October 2005. It represents a reactivation of an older, apparently relict (and well covered by a secular beech forest) landslide, which blocked Siriu Reservoir for several weeks and caused a major change in the sedimentation regime downstream of it. The volume of the displaced material reached almost 2.5 million m3, affecting a surface of more than 250,000 m2 and reducing the reservoir’s volume by almost 2 million m3. The landslide developed on a lithological contact of Paleogene flysch formations and features steep (40–50°) and high (up to 30 m) scarps, as well as complex inner sectors, of rotational, translational, and compresional movement. The assessment of landslide’s morphodynamic behavior is based on repeated geomorphological field mapping and measurements, differential Global Positioning System, and total station profiles, and mobile and fixed landmarks. This preliminary assessment contributes to the understanding of the behavior of old, peri-glacial landslide reactivations and also represents progress towards a better hazard assessment.  相似文献   
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A study of the orbital period variation of the W UMa system CK Bootis is made using an extended observational time base. The biperiodicity of the orbital period modulation is emphasized. Both detected periodicities (24.14 yr and 10.62 yr) cannot be explained through the light-time effect unless the companion would be a white dwarf as suggested by other authors, too. Moreover, we also argue that, nowadays at least, it seems that there is no causal relation between the orbital period variation and the recently discovered visual companion. Consequently, we infer that at least one of the two periodicities may be related to the magnetic activity cycles in the component stars of CK Boo, while the other periodicity could be related to the presence of a fourth companion in the system.  相似文献   
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New data from isotope geochronology (U-Pb, Sm-Nd) petrological study provide evidence of the Svecofennian age (~1.9 Ga) for eclogitization in the Fe-gabbro dyke inductile shear zones of Gridinrea. P-T estimates of eclogitization were computed using the THERIAK/DOMINO software. A close timing relationship between dyke magmatism and eclogitization is inferred.  相似文献   
58.
Wolframoxiolite with a sectorial distribution of components is described from Li-F granite. The ontogenetic features provide evidence for the primary origin of wolframoixiolite and geochemical evolution of the mineral-forming medium.  相似文献   
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