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41.
Results of the study of mineral, chemical, and isotopic compositions of carbonate rocks and ores from the Hukh Tag manganese ore manifestation suggest its hydrothermal origin. Secondary manganese carbonates and oxides were probably formed during several stages of tectonic reactivation with the participation of atmospheric (meteoric) waters. 相似文献
42.
The results of isotope-geochemical studies of carbonates of different mineral types from manganese and host rocks of the Famennian manganiferous formation of Pai-Khoi are reported. Kutnahorite ores are characterized by δ13C values from–6.6 to 1.3‰ and δ18O from 20.0 to 27.4‰. Rhodonite–rhodochrosite rocks of the Silovayakha ore occurrence have δ13C from–5.2 to–2.9 and δ18O from 25.4 to 24.3‰. Mineralogically similar rocks of the Nadeiyakha ore occurrence show the lighter carbon and oxygen isotopic compositions: δ13C from–16.4 to–13.1 and δ18O from 24.8 to 22.5‰. Similar isotopic compositions were also obtained for rhodochrosite–kutnahorite rocks of this ore occurrence: δ13C from–13.0 to–10.4‰ and δ18O from 24.6 to 21.7‰. Siderorodochrosite ores differ in the lighter oxygen and carbon isotopic compositions: δ18O from 18.7 to 17.6‰ and δ13C from–10.2 to–9.3‰, respectively. In terms of the carbon and oxygen isotopic compositions, host rocks in general correspond to marine sedimentary carbonates. Geological-mineralogical and isotope data indicate that the formation of the manganese carbonates was related to the hydrothermal ore-bearing fluids with the light isotopic composition of oxygen and carbon dissolved in CO2. The isotopic features indicate an authigenic formation of manganese carbonates under different isotopegeochemical conditions. 相似文献
43.
New isotope and mineral data on manganese carbonates of the Mazul deposit (Krasnoyarsk region) in combination with morphology of ore bodies suggest that the ores were formed in several stages with the involvement of meteoric solutions through infiltration and, possibly, exfiltration mechanisms. Based on the geological–geochemical data, manganese carbonates of the Mazul deposit may be ascribed to a new genetic subtype of the catagenesis (epigenesis) zone. 相似文献
44.
Lithology and Mineral Resources - The study of structural features along with carbon and oxygen isotope compositions made it possible to discriminate lithological rocks in deposits of the Karatau... 相似文献
45.
Brusnitsyn A. I. Kuleshov V. N. Sadykov S. A. Perova E. N. Vereshchagin O. S. 《Lithology and Mineral Resources》2020,55(6):445-467
Lithology and Mineral Resources - The Ushkatyn-III deposit is located 300 km west of Karaganda (Central Kazakhstan). It is classified as a weakly metamorphosed Atasu-type hydrothermal-sedimentary... 相似文献
46.
A quasi-constant hydrological front is found to form in the Pregolya River, flowing through Kaliningrad and Kaliningrad oblast, in the convergence zones of the slightly salt waters of the Vistula Lagoon and fresh river waters under the conditions circulation caused by positive and negative setups. Its formation and position are found to coincide with zones of hypoxia, especially in the places (hollows) within the city boundaries where the river depth is relatively large. A thick layer of liquid and semiliquid silts rich in organic carbon, especially in hollows; the dynamics of mobile exchange layer in bottom sediments at high temperature in summer; and the formation of the hydrological front with characteristic hydrophysical features along with an increase in the input of pollutants with municipal wastewater is a cause and a source of secondary pollution and deterioration of the environmental situation in the Pregolya River. 相似文献
47.
Lithology and Mineral Resources - Carbon and oxygen isotope compositions were determined in the pedogenic, sedimentary, and organogenic carbonates from Upper Permian (Vyatkian Stage) and Lower... 相似文献
48.
A. I. Brusnitsyn V. N. Kuleshov E. N. Perova A. N. Zaitsev 《Lithology and Mineral Resources》2017,52(3):192-213
The paper presents the results of study of ferromanganese carbonate rocks in the Sob area (Polar Urals), which is located between the Rai-Iz massif and the Seida–Labytnangi Railway branch. These rocks represent low-metamorphosed sedimentary rocks confined to the Devonian carbonaceous siliceous and clayey–siliceous shales. In terms of ratio of the major minerals, ferromanganese rocks can be divided into three varieties composed of the following minerals: (1) siderite, rhodochrosite, chamosite, quartz, ± kutnahorite, ± calcite, ± magnetite, ± pyrite, ± clinochlore, ± stilpnomelane; (2) spessartite, rhodochrosite, and quartz, ± hematite, ± chamosite; (3) rhodochrosite, spessartite, pyroxmanite, quartz ± tephroite, ± fridelite, ± clinochlore, ± pyrophanite, ± pyrite. In all varieties, the major concentrators of Mn and Fe are carbonates (rhodochrosite, siderite, kutnahorite, Mn-calcite) and chlorite group minerals (clinochlore, chamosite). The chemical composition of rocks is dominated by Si, Fe, Mn, carbon dioxide, and water (L.O.I.): total SiO2 + Fe2O 3 tot + MnO + L.O.I. = 85.6?98.4 wt %. The content of Fe and Mn varies from 9.3 to 55.6 wt % (Fe2O 3 tot + MnO). The Mn/Fe ratio varies from 0.2 to 55.3. In terms of the aluminum module AlM = Al/(Al + Mn + Fe), the major portion of studied samples corresponds to metalliferous sediments. The δ13Ccarb range (–30.4 to–11.9‰ PDB) corresponds to authigenic carbonates formed with carbon dioxide released during the microbial oxidation of organic matter in sediments at the dia- and/or catagenetic stage. Ferromanganese sediments were likely deposited in relatively closed seafloor zones (basin-traps) characterized by periodic stagnation. Fe and Mn could be delivered from various sources: input by diverse hydrothermal solutions, silt waters in the course of diagenesis, river discharges, and others. The diagenetic delivery of metals seems to be most plausible. Mn was concentrated during the stagnation of bottom water in basin-traps. Interruption of stagnation promoted the precipitation of Mn. The presence of organic matter fostered a reductive pattern of postsedimentary transformations of metalliferous sediments. Fe and Mn were accumulated initially in the oxide form. During the diagenesis, manganese and iron oxides reacted with organic matter to make up carbonates. Relative to manganese carbonates, iron carbonates were formed under more reductive settings and higher concentrations of carbon dioxide in the interstitial solution. Crystallization of manganese and iron silicates began already at early stages of lithogenesis and ended during the regional metamorphism of metalliferous sediments. 相似文献
49.
I. A. Gotyur Yu. V. Kuleshov A. B. Makov S. S. Suvorov N. V. Shirshov G. G. Shchukin 《Russian Meteorology and Hydrology》2014,39(6):387-394
A complex system of the operational acquisition, processing, and presentation of meteorological data is developed according to the requirements to cosmodrome weather support. The proposed system allows for the high efficiency of space rocket launches by making prompt decisions based on the information provided by the weather support system. 相似文献
50.
V. N. Kuleshov 《Lithology and Mineral Resources》2012,47(4):305-318
The carbon and oxygen isotopic compositions in rocks and ores of the Ulutelyak (Bashkortostan) manganese deposit of the Lower Permian (P1kg) are studied. Values of ??13C, ?? (PDB) and ??18O, ?? (SMOW) show the following range: from ?3.8 to 3.3 and from 22.0 to 29.6, respectively, in manganese oxide-carbonate ores; from 2.7 to 4.1 and from 28.8 to 29.7, respectively, in non-ore carbonate-clayey interbeds of the ore member; and from 2.8 to 4.5 and from 29.5 to 30.0, respectively, in the underlying and overlying limestones. Lithological features and isotope data suggest that manganese carbonates were formed at the postsedimentary stage of rock transformation due to metasomatic replacement of the primary cyanobacterial sedimentary carbonates by the elisional manganiferous solutions. 相似文献