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Lithology and Mineral Resources - The results of long-term studies of the localization conditions, morphology, structure, mineral and chemical compositions of modern ocean sulfide ores, carbonate... 相似文献
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I. F. Gablina L. L. Demina O. B. Dmitrenko N. S. Os’kina E. A. Popova T. A. Khusid V. V. Shilov 《Oceanology》2011,51(3):476-490
The first thorough analysis of microfossils from ore-bearing sediments of the Ashadze-1 hydrothermal field in the Mid-Atlantic
Ridge sampled during cruise 26 of the R/V Professor Logachev in 2005 revealed the substantial influence of hydrothermal processes on the preservation of planktonic calcareous organisms,
as well as on the preservation and composition of the benthic foraminifers. From the lateral and vertical distribution patterns
and the secondary alterations of the microfossils, it is inferred that the main phase of the hydrothermal mineralization occurred
in the Holocene. Heavy metals (Cu, Co, Cr, and Ag) were accumulated by foraminiferal tests and in their enveloping Fe-Mn crusts.
The distribution of authigenic minerals replacing foraminiferal tests demonstrates local zoning related to the hydrothermal
activity. There are three mineral-geochemical zones defined: the sulfide zone, the zone with an elevated Mg content, and zone
of Fe-Mn crusts. 相似文献
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T.?A.?KhusidEmail author N.?S.?Os’kina N.?P.?Lukashina I.?F.?Gablina N.?V.?Libina A.?G.?Matul 《Stratigraphy and Geological Correlation》2018,26(1):109-120
Comparison of benthic foraminiferal assemblages from the core obtained within the Peterburgskoe ore field (Mid-Atlantic Ridge) and from the core taken five kilometers away from the ore field revealed evident differences in their composition, in the appearance of their shells, and also in the benthic–plankton species ratio. It was noted that the foraminiferal assemblage from the ore-bearing sediments of the Petersburg field was characterized by a higher relative content of benthic species and a large number of chemically altered and broken shells. The first occurrence of the species Osangularia umbonifera, which is able to exist in lowoxygen and CaCO3-undersaturated bottom waters at the boundary of biogenic sediments surrounding the ore field and in the ore-bearing sediments, was established. In the core section sampled beyond the ore field, the composition of foraminiferal assemblages differs insignificantly from typical oceanic ones. 相似文献
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Gablina I. F. Dmitrenko O. B. Khusid T. A. Libina N. V. 《Lithology and Mineral Resources》2019,54(6):511-523
Lithology and Mineral Resources - Based on materials obtained during Cruise 37 of the R/V Professor Logatchev in the Russian exploration area, the species composition, distribution, and... 相似文献
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V. Yu. Rusakov V. V. Shilov B. N. Ryzhenko I. F. Gablina I. A. Roshchina T. G. Kuz’mina N. N. Kononkova I. G. Dobretsova 《Geochemistry International》2013,51(8):646-669
New material from eight columns recovered during Cruise 32 of the R/V Professor Logachev in 2009 was used to explore the lithological facies, biostratigraphy, mineralogy, and geochemistry of sediments from the northwestern (active) and eastern (inactive) hydrothermal vent fields of the Semenov cluster. Mineral types of sediments were distinguished, and a general scheme was proposed for the vertical structure of the hydrothermal-sedimentary sequence overlying massive sulfide ores. It was found that the ore-bearing sediments exhibit a vertical zoning in the distribution of mineral assemblages, which are controlled by oxygen activity. The mechanisms of the formation of atacamite, CuCl2 · 3Cu(OH)2, which is a widespread mineral in red iron-oxide bodies replacing sulfides (gossans), were evaluated. 相似文献
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I. F. Gablina I. G. Dobretsova E. V. Narkevskii A. N. Gustaitis T. A. Sadchikova N. V. Gor’kova A. T. Savichev A. D. Lyutkevich O. M. Dara 《Lithology and Mineral Resources》2017,52(5):335-357
Based on materials obtained in Cruises 33 and 34 of the R/V Professor Logachev, the paper addresses formation conditions, morphology, structures, mineral composition of the present-day oceanic sulfide ores, and their relationships with the host (biogenic carbonate) bottom sediments in the 19°–20° N MAR (Zenith-Victoria and Petersburg hydrothermal fields) region. The grain size distribution, mineral composition of the carbonate (background) and ore-hosting sediments, as well as physicochemical parameters of their interstitial waters, are examined. The results suggest a significant role of hydrothermal-metasomatic processes in the formation of ores and ore-bearing sediments. A model is proposed for the formation of sulfide mineralization in oceanic sediments at the geochemical barrier in the zone of their interaction with the acid hydrothermal (diffuse-type) ore-bearing solutions delivered from rocks of the ocean floor. 相似文献
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N. N. Mozgova Yu. S. Borodaev I. F. Gablina G. A. Cherkashev T. V. Stepanova 《Lithology and Mineral Resources》2005,40(4):293-319
The composition of ore minerals in MAR sulfide occurrences related to ultramafic rocks was studied using methods of mineragraphy, electron microscopy, microprobe analysis, and X-ray analysis. The objects are located at various levels of the maturity of sulfide mounds owing to differences in age, duration, and degree of activity of the following hydrothermal systems: generally inactive Logatchev-1 field (up to 66.5 ka old), inactive Logatchev-2 field (3.9 ka), and generally active Rainbow field (up to 23 ka). Relative to MAR submarine ore occurrences in the basalt substrate, mineralization in the hydrothermal fields mentioned above is characterized by high contents of Au, Cd, Co, and Ni, along with the presence of accessory minerals of Co and Ni. The studied mounds differ in quantitative ratios of major minerals and structural-textural features of ores that suggest their transformation. Ores in the Logatchev-1 field are characterized by the highest Cu content and the development of a wide range of multistage contrast exsolution structures of isocubanite and bornite. In the Logatchev-2 field, sphalerite-chalcopyrite and gold-arsenic exsolution structures are present, but isocubanite exsolution structures are less diverse and contrast. The Rainbow field is marked by the presence of homogenous isocubanite and the subordinate development of exsolution structures. We have identified four new phases in the Cu-Fe-S system. Phases X and Y (close to chalcopyrite and isocubanite, respectively) make up lamellae among isocubanite exsolution products in Logatchev-1 and Logatchev-2. Phase Y includes homogenous zones in zonal chimneys of the Rainbow field. Phases A and B are formed in the orange bornite domain at low-temperature alteration of chalcopyrite in the Logatchev-1 field. Mineral assemblages of the Cu-S system are most abundant and diverse in the Logatchev-1 field, but their development is minimal in the Logatchev-2 field where mainly Cu-poor sulfides of the geerite-covellite series have been identified. Specific features of mineral assemblages mentioned above reflect the maturity grade of sulfide mounds and can serve as indicators of maturity.__________Translated from Litologiya i Poleznye Iskopaemye, No. 4, 2005, pp. 339–367.Original Russian Text Copyright © 2005 by Mozgova, Borodaev, Gablina, Cherkashev, Stepanova. 相似文献
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Physicochemical conditions of the migration and concentration of Cu in sedimentary rock, specific features of the formation of large and unique deposits of cupriferous sandstones and shales, distribution of copper deposits in the stratigraphic scale, and causes responsible for the reduction of Cu accumulation from Proterozoic to Cenozoic are considered. Genetic link of cupriferous sandstones and shales with arid red molassic rocks is shown. Conditions and periodicity of formation of the ore-generating red rocks are considered. An explanation for periodicity of maximum Cu accumulation in the Earth’s history is proposed. 相似文献
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New hydrothermal ore fields in the Mid-Atlantic Ridge: Zenith-Victoria (20°08′ N) and Petersburg (19°52′ N) 总被引：1，自引：0，他引：1