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Dr. D. A. Velikoslavinsky 《Mineralogy and Petrology》1994,50(1-3):35-42
Summary This paper deals with the chemical composition of biotites from rapakivi granites. For this purpose, 61 chemical analyses of biotites from composite anorthosite-rapakivi plutons in the Fennoscandian and Ukranian shields were used. Figurative points of the biotite composition were plotted on diagrams designed for biotites byFoster (1960),Winchell (1949) andVelikoslavinsky (1972). Consideration of the diagrams shows that a) the biotites from rapakivi granites have exotic composition not characteristic of other biotites from other igneous rocks, b) that they belong to the annite-siderophyllite series and c) that they crystallized at low pressures and high temperatures. Model crystallization temperatures range from 760° (early intrusive phases) down to less than 435° (late intrusive phase).
With 3 figures 相似文献
Biotit von Rapakivi
Zusammenfassung Diese Arbeit hat die chemische Zusammensetzung von Biotit aus Rapakivi Graniten zum Thema. 61 Biotitanalysen von Anorthosit-Rapakivi Plutonen aus dem fennoskandischen und ukrainischen Schild werden präsentiert. Die Zusammensetzung der Biotite wird unter Verwendung von Diagrammen, die vonFoster (1960),Winchell (1949) undVelikoslavinsky (1972) entwickelt wurden, diskutiert. Diese Diagramme zeigen, daß a) Biotite aus Rapakivi eine, im Vergleich zu Biotiten aus anderen magmatischen Gesteinen, untypische Zusammensetzung haben, b) diese Biotite der AnnitSiderophyllit Serie zuzurechnen sind und c) diese Biotite bei niedrigem Druck und hoher Temperatur kristallisierten. Die Kristallisationstemperaturen reichen von 760° in den granitischen Frühphasen bis unter 435°C in den intrusiven Spätphasen.
With 3 figures 相似文献
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A. B. Kotov T. M. Skovitina V. P. Kovach S. D. Velikoslavinsky D. V. Lopatin E. V. Sklyarov E. V. Tolmacheva O. V. Bobrovskaya 《Doklady Earth Sciences》2017,475(1):758-761
It has been demonstrated on basis of Sm–Nd isotopic analyses of the Cenozoic sands from the Chara and Tokkin Basins in the eastern flank of the Baikal rift zone that the Chara–Olekma Geoblock of the Aldan Shield is an area of intense crust growing processes occurred not only in the Paleoarchaean but in the Mesoarchaean as well. 相似文献
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S. D. Velikoslavinsky A. B. Kotov E. V. Sklyarov T. M. Skovitina E. V. Tolmacheva O. A. Sklyarova N. S. Prokopov 《Doklady Earth Sciences》2017,474(2):631-635
In terms of chemical composition, the Late Quaternary geyserites of the Olkhon area and Olkhon Island are subdivided into the ferrosiliceous and carbonate–siliceous groups and are commonly characterized by low concentrations of rare elements. In several cases, the geyserites are enriched in Fe, Mn, Cr, Sb, As, and Y. Regardless of the chemical composition of geyserite, the key components of the gas phase are H2O, CO2, and CH4. The parent matter for the geyserites was constituted by aqueous solutions (fluids) of 400°C and higher temperatures, silica-saturated, and enriched in carbon dioxide and hydrocarbons, as well as in some ore components. 相似文献
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Kovach V. P. Kotov A. B. Salnikova E. B. Popov N. V. Velikoslavinsky S. D. Plotkina J. V. Wang K.-L. Fedoseenko A. M. 《Doklady Earth Sciences》2020,494(2):767-772
Doklady Earth Sciences - This work presents new U–Pb ID-TIMS geochronological data obtained for the rocks of the metagabbro–diorite–tonalite complex of the Olondo fragment of the... 相似文献
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I.V. Buchko A.A. Sorokin E.B. Sal''nikova A.B. Kotov A.M. Larin A.E. Izokh S.D. Velikoslavinsky S.Z. Yakovleva 《Russian Geology and Geophysics》2007,48(12):1026-1036
We present new data on the age and geochemistry of the Veselyi and Petropavlovsk ultramafic-mafic massifs of the Selenga-Stanovoy (West Stanovoy) superterrane on the southeastern framing of the North Asian craton. The massifs are composed of rocks of peridotitewebsterite-gabbro and peridotite-gabbro-monzodiorite associations, respectively. The latter combine normal, subalkalic, and alkaline rocks and thus are of diverse composition: from ultrabasites and pyroxenites through gabbroids to monzodiorites. The U-Pb zircon age of these massifs is 154 ± 1 and 159 ± 1 Ma, respectively, which permits them to be referred to as the youngest rocks of ultramafic-mafic complexes on the southern framing of the North Asian craton. The rocks of the studied massifs are enriched in LILE (K, Rb, Sr, Ba, LREE) and are depleted in HFSE (Zr, Nb, Hf, Ta). These rocks formed, most likely, in the rear of subduction zone or in the setting of the subducting-slab detachment. 相似文献
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Rytsk E. Yu. Andreev A. A. Tolmacheva E. V. Kuznetsov A. B. Velikoslavinsky S. D. Fedoseenko A. M. 《Doklady Earth Sciences》2021,498(1):367-371
Doklady Earth Sciences - This article presents the results of U–Pb geochronological study of gneiss-granites of the Mamskaya zone. The age estimate of 1874 ± 9 Ma (SIMS method) obtained... 相似文献
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V. P. Kovach A. B. Kotov D. P. Gladkochub E. V. Tolmacheva S. D. Velikoslavinsky B. M. Gorokhovsky V. N. Podkovyrov N. Yu. Zagornaya Yu. V. Plotkina 《Doklady Earth Sciences》2018,482(1):1138-1141
Results of U–Th–Pb LA–ICP–MS analysis of detrital zircons from metasandstones of the Chiney Subgroup (Udokan Group, Aldan Shield) have been obtained. It has been revealed that rocks of the Paleoproterozoic (about 1.90, 1.98, and 2.50 Ga) and Neoarchean (2.55 and 2.72 Ga) were their provenance sources. Deposition of the Chiney Subgroup occurred in the interval 1.87–1.90 Ga and was separated in time from the accumulation of the Kodar Subgroup siliciclastics (2.1–2.3 Ga). 相似文献