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1.
N. G. Makarenko Yu. A. Nagovitsyn L. M. Karimova O. A. Kruglun 《Geomagnetism and Aeronomy》2013,53(7):882-886
The possibility to apply long-term regional series to reconstruct the Earth’s global temperature in the past is considered. It is shown using symbolic analysis methods that significant (on the so-called order patterns) are relations of time series of St. Petersburg temperature with certain regional and global series. New sets of global temperature reconstructions, starting from the mid-18th century, are constructed on the basis of the previously proposed MSR and DPS methods. 相似文献
2.
N. V. Chukanov A. A. Mukhanova R. K. Rastsvetaeva D. I. Belakovsky S. M?ckel O. V. Karimova S. N. Britvin S. V. Krivovichev 《Geology of Ore Deposits》2011,53(7):583-590
Oxyphlogopite is a new mica-group mineral with the idealized formula K(Mg,Ti,Fe)3[(Si,Al)4O10](O,F)2. The holotype material came from a basalt quarry at Mount Rothenberg near Mendig at the Eifel volcanic complex in Rhineland-Palatinate,
Germany. The mineral occurs as crystals up to 4 × 4 × 0.2 mm in size encrusting cavity walls in alkali basalt. The associated
minerals are nepheline, plagioclase, sanidine, augite, diopside, and magnetite. Its color is dark brown, its streak is brown,
and its luster is vitreous. D
meas = 3.06(1) g/cm3 (flotation in heavy liquids), and D
calc = 3.086 g/cm3. The IR spectrun does not contain bands of OH groups. Oxyphlogopite is biaxial (negative); α = 1.625(3), β = 1.668(1), and
γ = 1.669(1); and 2V
meas = 16(2)° and 2V
calc = 17°. The dispersion is strong; r < ν. The pleochroism is medium; X > Y > Z (brown to dark brown). The chemical composition is as follows (electron microprobe, mean of 5 point analyses, wt %; the ranges
are given in parentheses; the H2O was determined using the Alimarin method; the Fe2+/Fe3+ was determined with X-ray emission spectroscopy): Na2O 0.99 (0.89–1.12), K2O 7.52 (7.44–7.58), MgO 14.65 (14.48–14.80), CaO 0.27 ((0.17–0.51), FeO 4.73, Fe2O3 7.25 (the range of the total iron in the form of FeO is 11.09–11.38), Al2O3 14.32 (14.06–14.64), Cr2O3 0.60 (0.45–0.69), SiO2 34.41 (34.03–34.66), TiO2 12.93 (12.69–13.13), F 3.06 (2.59–3.44), H2O 0.14; O=F2 −1.29; 99/58 in total. The empirical formula is (K0.72Na0.14Ca0.02)(Mg1.64Ti0.73Fe0.302+ Fe0.273+Cr0.04)Σ2.98(Si2.59Al1.27Fe0.143+ O10) O1.20F0.73(OH)0.07. The crystal structure was refined on a single crystal. Oxyphlogopite is monoclinic with space group C2/m; the unit-cell parameters are as follows: a = 5.3165(1), b = 9.2000(2), c = 10.0602(2) ?, β = 100.354(2)°. The presence of Ti results in the strong distortion of octahedron M(2). The strongest lines of the X-ray powder diffraction pattern [d, ? (I, %) [hkl]] are as follows: 9.91(32) [001], 4.53(11) 110], 3.300(100) [003], 3.090(12) [112], 1.895(21) [005], 1.659(12) [−135], 1.527(16)
[−206, 060]. The type specimens of oxyphlogopite are deposited at the Fersman Mineralogical Museum in Moscow, Russia; the
registration numbers are 3884/2 (holotype) and 3884/1 (cotype). 相似文献
3.
Regional Estimation of Fresh Groundwater Vulnerability: Methodological Aspects and Practical Applications 总被引：1，自引：0，他引：1
Two independent methods for estimating groundwater vulnerability to pollution are described. The methods are used for regions with different geological and hydrogeological conditions. A new combined approach taking into account the physicochemical processes that take place in all parts of the protected zone is proposed. 相似文献
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A. E. Zadov V. M. Gazeev O. V. Karimova N. N. Pertsev I. V. Pekov E. V. Galuskin I. O. Galuskina A. G. Gurbanov D. I. Belakovsky S. E. Borisovsky P. M. Kartashov A. G. Ivanova O. V. Yakubovich 《Geology of Ore Deposits》2011,53(8):775-782
A new mineral of the neptunite group, magnesioneptunite KNa2Li(Mg,Fe)2Ti2Si8O24, a Mg-dominant analogue of neptunite and manganoneptunite, has been found in the Upper Chegem caldera near Mount Lakargi, Kabardino-Balkaria, the North Caucasus, Russia in a xenolith of altered sandstone located between skarnified carbonate xenoliths and ignimbrite. Magnesioneptunite occurs as nearly isometric grains and aggregates up to 0.1 mm in size in the cores of some grains of a Mg-rich variety of neptunite with Mg/(Fe + Mn) = 0.7?1.0. The chemical composition of magnesioneptunite with a maximum Mg content is as follows, wt %: 3.63 K2O, 8.21 Na2O, 1.73 Li2O, 6.47 MgO, 0.04 MnO, 5.87 FeO, 0.07 Al2O3, 18.73 TiO2, 56.88 SiO2, 99.62 in total. The empirical formula is (K0.67Na0.32Ca0.01)Σ1.00Na2.06Li1.00 · (Mg1.39Fe 0.71 2+ )Σ2.10(Si7.90Al0.01)Σ7.91O24. Grains of magnesioneptunite are dark brown to red-brown, translucent, with vitreous luster. D calc = 3.15 g/cm3, and the Mohs hardness is 5–6. Cleavage parallel to the (110) is perfect. The new mineral is optically biaxial, positive, α = 1.697(2), β = 1.708 (3), γ = 1.725(3), 2V meas = 45(15)°. The mineral is associated with quartz, alkali feldspar, rutile, aegirine, and neptunite. Magnesioneptunite and the Mg-rich variety of neptunite were formed as products of ilmenite alteration. Magnesioneptunite is monoclinic, C2/c; unit-cell parameters: a = 16.327(7), b = 12.4788(4), c = 9.9666(4) Å, β = 115.6519(5)°, V = 1830.5(1) Å3, Z = 4. The type specimen is deposited at the Fersman Mineralogical Museum of the Russian Academy of Sciences, Moscow. 相似文献
6.
A decadal historical satellite data analysis for flood hazard evaluation: A case study of Bihar (North India) 
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下载免费PDF全文 Panchagnula Manjusree Chandra Mohan Bhatt Asiya Begum Goru Srinivasa Rao Veerubhotla Bhanumurthy 《Singapore journal of tropical geography》2015,36(3):308-323
Flood is one of the major recurrent natural disasters faced by the state of Bihar in north India. In the present study the authors assess the severity of flood hazard in Bihar, using 128 decadal historical satellite datasets acquired during different flood magnitudes during 1998 to 2010. The satellite‐based observations have been analysed in conjunction with the hydrological data, for assessing the frequency of inundation, severity of flood hazard and cropped land under flood hazard. This study assesses the spatial distribution of flooding and creation of systematic flood hazard database, which can be analysed from a spatial dimension in GIS. It is observed that about 24.56 lakh ha of the state's area and about 15.85 lakh ha of the cropped area are vulnerable to flood hazard. North Bihar is more vulnerable to flooding; 8 of the 10 areas identified as worst flood‐affected districts lie in this region. 相似文献
7.
We reformulate the original model of Hatchell and Bourne and Røste, Stovas and Landrø that couples fractional velocity change to subsurface strain via a fundamental constant R. The new model combines elastic compressibility of a dual‐porosity system for a sand–shale mixture with horizontal planes of inter‐granular weakness. The majority of observed R‐factor magnitudes from post‐stack 4D seismic data in both the reservoir and overburden can thus be explained. R is predicted to depend strongly on lithology and also initial strain state. The model is also extended to predict the observed angle‐dependence of time‐lapse time‐shifts from pre‐stack data. An expression for the gradient of time‐shift with incidence angle is obtained in terms of the background VP/VS, and also the ratio of tangential to normal compliances BT/BN representing loss or creation of inter‐granular coupling. If accurately estimated from data, this compliance ratio can be used as an additional parameter to assess the post‐production state of the overburden. It is concluded that whilst R remains the over‐arching parameter controlling the magnitude of time‐shifts measured from 4D seismic data, BT/BN is a subtler parameter that may also prove of future value. 相似文献
8.
Themain purpose of this paper is to describe the evolution of the magnetic field of active regions of the Sun in the context of Minkowski functionals: the Euler characteristic and perimeter calculated on the excursion set for a specified level. Themethods of geometry of random fields was applied to the MDI SOHO magnetogram, containing flaring active regions. The results demonstrated that morphological functional tracked the dynamic scenarios of the magnetic fields preceded by flares or accompanying them. 相似文献
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Mordvinov A.V. Salakhutdinova I.I. Plyusnina L.A. Makarenko N.G. Karimova L.M. 《Solar physics》2002,211(1-2):241-253
We investigate the topological properties and evolution of background magnetic fields on synoptic maps from Wilcox Solar Observatory using mathematical morphology methods in terms of the Minkowski functionals. The total length of the neutral line, the total areas occupied by positive and negative polarities, and the Euler characteristics of background magnetic fields vary over an eleven-year cycle. Changes in the length of the neutral line that separates the polarities of the background magnetic field correlate well with flare activity. A time–longitude analysis of solar flare activity revealed a complicated organization and rotation of the entire flare ensemble. On the time–longitude diagram, flare activity is organized into the patterns which follow the rearrangements in background magnetic field and exhibit coexisting and alternating modes of rigid rotation. The character of rotation of the entire flare ensemble is similar to the rotation of background magnetic fields. The emergence of background magnetic fields and changes in their topology and rotation are often accompanied by enhancements in flare activity. A comparative analysis of the topological changes in background magnetic fields and flare activity reveals their causal relation. 相似文献