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Motuzova G. V. Lukina N. V. Nikonov V. V. Dauval'ter M. V. Zorina A. V. 《Water Resources》2004,31(3):297-302
The concentrations of mobile compounds of S, Cu, and Ni are determined in podzol soils in the Murmansk region taken at different distances from Severonikel Copper–Nickel Plant and their variations are analyzed. The concentrations are found to have an effect on the distribution of these elements in lysimetric and subsoil waters. 相似文献
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P.V. Koval L.D. Zorina N.A. Kitajev A.M. Spiridonov S. Ariunbileg 《Journal of Geochemical Exploration》1991,40(1-3)
Chemical composition, unit cell parameters, and trace elements of tourmalines from Mesozoic gold-quartz-sulphide and gold-bearing copper-porphyry ore-magmatic systems of the Trans-Baikal area and Mongolia show that they belong to the specific schorl-dravite highly ferruginous oxytourmaline series. They are low in alumina (Al2O3 = 16–33%) and have MgO contents (up to 10%) and Fe2O3 (1%). There is a direct correlation of unit cell parameters (a,c,V) with total iron, which permits composition estimates from X-ray diffraction analyses. As a rule, these tourmalines contain high concentrations of Au, Pb and Cu, which are mainly hosted by inclusions of native gold and ore minerals. The highest As abundances are contained in the tourmalines of the copper-porphyry field.Two trends of isomorphic replacement are related to increasing Fe content of oxyferruginous tourmalines:(1) “Acid leaching” trend (less ferruginous part of the series) Mg + Fe2+ + 4Al + 40 4Fe3+ + 2 + 4(OH,F); and (2) “conjugate deposition” trend Mg + 1.5Fe2+ + 1.5Al + 4(OH,F) 4Fe3+ + 4O.These features distinguish tourmalines from gold-bearing systems from schorl-dravites of tin and rare-metal deposits. They may be used in metallogenic analyses, interpretation of the origin of primary and secondary anomalies, and assessment of the type and zonation of ore fields. 相似文献
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S. O. Zorina 《Stratigraphy and Geological Correlation》2007,15(3):267-276
The work is aimed at litho-, bio- and magnetostratigraphic subdivision of the Middle-Upper Jurassic sedimentary succession in the northeast of the Ul’yanovsk-Saratov depression (the East Russian plate). Problems of regional and interregional correlation of distinguished subdivisions are considered. As is shown, the ammonite biostratigraphy is most effective method for solving problems of chronostratigraphy. 相似文献
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V. Yu. Prokof’ev N. S. Bortnikov V. A. Kovalenker S. F. Vinokurov L. D. Zorina A. D. Chernova S. G. Kryazhev A. N. Krasnov S. A. Gorbacheva 《Geology of Ore Deposits》2010,52(2):81-113
The chemistry, REE patterns, and carbon and oxygen isotopic compositions of carbonates from ore veins of the Darasun deposit
are discussed. In addition to the earlier described siderite, calcite, and carbonates of the dolomite-ankerite series, kutnahorite
is identified. The total REE content in Fe-Mg carbonates of the dolomite-ankerite series (2.8–73 ppm) is much lower than in
later calcite (18–390 ppm). δ13C of Fe-Mg carbonates and calcite varies from +1.1 to −6.7‰ and from −0.9 to −4.9‰, respectively. δ18O of Fe-Mg carbonates and calcite varies from +17.6 to 3.6‰ and from +15.7 to −0.5‰, respectively. The REE sum and carbon
and oxygen isotopic compositions reveal zonal distribution relative to the central granodiorite porphyry stock. The correlation
between the carbon and oxygen isotopic compositions and REE sum reflects variations in the physicochemical formation conditions
and composition of ore-forming fluid. The isotopic composition of fluid is calculated, and possible sources of its components
are considered. Earlier established evidence for a magmatic source of ore-forming fluid and participation of meteoric water
in ore formation is confirmed. Geochemical evidence for interaction of ore-forming fluid with host rocks is furnished. The
relationships between the REE sum, on the one hand, and carbon and oxygen isotopic compositions of hydrothermal ore-forming
fluid, on the other, are established. 相似文献
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M. I. Kuz’min Yu. P. Troshin S. M. Boiko E. A. Razvozzhaeva L. D. Zorina D. Kh. Martikhaeva 《Geology of Ore Deposits》2010,52(3):252-259
The carbonaceous matter filling cavities in sulfide-quartz veins at the Kurultyken hydrothermal base-metal deposit in the
Khapcheranga ore district, Transbaikal region, was studied using chromatography/mass spectrometry, X-ray diffraction, thermal
and isotopic analyses, and IR spectroscopy. It was established that carbonaceous matter was a maltha composed of polycyclic
aromatic hydrocarbons (PAHs). Chrysene, pyrene, and benzpyrelene identified among PAHs are evidence for the hydrothermal origin
of the initial carbonaceous matter of maltha. The main mass of carbonaceous matter was synthesized under reductive conditions
and at a low temperature, i.e., at the final stage of base-metal ore formation. Nevertheless, the thermometric data indicate
that part of the carbonic compounds could have formed at 480°C, i.e., at the high-temperature stage of the postmagmatic process.
The contribution of host rocks as a source of carbonaceous matter was minimal. 相似文献
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S.O. Zorina 《Russian Geology and Geophysics》2009,50(5):430-437
The generalized eustatic and tectonoeustatic models developed by the author are tested on Lower Cretaceous deposits of the eastern part of the Russian Plate. The models are applicable to facies analysis of sections of epicontinental basins with mainly slope sedimentation. They demonstrate possible variations in section lithology depending on the rate of eustatic changes and the intensity and direction of epeirogenic movements. It has been revealed that the Lower Cretaceous sections in the east of the Russian Platform formed as a result of the synchronous global eustasy and regional epeirogeny. Superposition of the global eustatic curve onto the Lower Cretaceous chronostratigraphic chart of the eastern part of the platform showed that global eustasy, periodically concealed by regional epeirogeny, played a crucial role in the Early Cretaceous history of the study area. Regional epeirogenic and eustatic curves were constructed. The epeirogenic curve demonstrates the contribution of vertical tectonic movements to the overall eustatic-epeirogenic result recorded on a regional eustatic curve. The latter was constructed from the analysis of the spatial and temporal changes in the stratigraphic position of formations and strata and transgressive surfaces ranking. Eustatic cycles of different ranks, from elementary (systems tracts) to regional scale, have been recognized. In the rank of largest lithostratigraphic units, three sequences are revealed: Valanginian (RP-1K), Upper Hauterivian–Upper Aptian (RP-2K), and Albian (RP-3K), which reflect the crucial stages of the Early Cretaceous evolution of the eastern Russian Plate. The eustatic-epeirogenic processes during accumulation of formations and strata from Early Berriasian to Late Albian (145.5–99.6 Ma) are considered. It is shown that the division of the studied composite section into sequences permits precise prediction of diverse solid minerals. 相似文献
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Dmitry A. Ruban Svetlana O. Zorina Clinton P. Conrad Nadezhda I. Afanasieva 《Proceedings of the Geologists' Association. Geologists' Association》2012,123(1):7-18
Chronostratigraphically-justified records of regional transgressions and regressions are important for understanding the nature of the Paleocene shoreline shifts on a global scale. Review of previously synthesized data from 7 tectonically “stable” regions, namely the eastern Russian Platform, Northwestern Europe, Northwestern Africa, Northeastern Africa, the Arabian Platform, the northern Gulf of Mexico, and Southern Australia, allows a comparison of transgressions and regressions interpreted in these regions. No common patterns are found in the early Danian and late Selandian, which reflects small or zero eustatic fluctuations that are overwhelmed locally on coastlines by regional tectonic motions and local changes in dynamic support of surface topography by mantle flow. Sea level was stabilized during these stages by a warm climate and a lack of planetary-scale tectonic changes. We have detected a middle–late Danian regression that occurred in 5 of 7 study regions, and can be explained by glacial advance at ～62–63 Ma or by concurrent subduction of the Izanagi–Pacific ridge beneath eastern Asia. An early–middle Selandian transgression also occurred in 5 regions, probably, as a result of a hyperthermal at ～61 Ma that coincided with emplacement of large igneous provinces in the oceanic domain. Both events are characterized by significant diachroneity, which can also be explained by the influence of regional tectonic subsidence or uplift. Results of the present study permit us to propose a tentative framework for a new Paleocene eustatic curve that is constrained globally using available records of transgressions and regressions. 相似文献
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S. O. Zorina 《Doklady Earth Sciences》2012,444(2):702-705
A methodical approach to assessment of the role played by vertical tectonic movements in the of tectonic-eustatic cyclicity and the facial appearance of the Middle Jurassic-Lower Cretaceous deposits on the eastern part of the East European Craton has been suggested. Resulting from comparison between the global and regional eustatic curves, the modeling of probable versions of the lithological composition for sediments during eustatic oscillations, and the comparison of modeling results with the chronostratigraphic scheme, the global eustatic component and regional ??tectonic noise?? have been identified. It has been found that the vertical tectonic movements formed the boundaries of the most distinguished cyclites on the eastern part of the East European Craton. The spatial-temporal uniformity in the material composition of cyclites, related to the long periods of stable high-stand sea level, caused their mineralogenic specialization for a broad range of non-ore mineral resources. 相似文献
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Doklady Earth Sciences - Based on the results of studying the lithological–geochemical features of the Upper Jurassic–Lower Cretaceous mudrocks and black shales in the Eastern Russian... 相似文献