Инд. авторы:	Nastavko A.V., Borodina E.V., Izokh A.E.
Заглавие:	Petrological and mineralogical features of volcanic rocks from the central Kuznetsk Basin (southern Siberia)
Библ. ссылка:	Nastavko A.V., Borodina E.V., Izokh A.E. Petrological and mineralogical features of volcanic rocks from the central Kuznetsk Basin (southern Siberia) // Russian Geology and Geophysics. - 2012. - Vol.53. - Iss. 4. - P.334-346. - ISSN 1068-7971. - EISSN 1878-030X.
Внешние системы:	DOI: 10.1016/j.rgg.2012.02.010; SCOPUS: 2-s2.0-84858732255;
Реферат:	eng: The Kuznetsk Basin volcanic rocks are close in age (from 252.3 ± 0.6 to 246.2 ± 1.4 Ma) to the traps of the West Siberian Plate and Siberian craton, which formed as a result of the Permo-Triassic plume activity. The geologic and petrographic features evidence that the andesitic basalts exposed in the Karakan and Elbak quarries are effusive rocks; most of them are andesitic basalts, and the rest are trachyandesitic basalts. The mineral composition is as follows: olivine Fo 59-66, plagioclase An 47-60, and clinopyroxene En 47-42Fs 25-12Wo 42-33; Mg# = 82-63. Using the COMAGMAT 3.5 program, the magma crystallization conditions during the andesitic-basalt formation were determined: 1109-1105 oC, buffer QFM-NNO. The studied rocks are enriched in LREE ((La/Yb) ch = 4.7-7.5) and are depleted in HREE ((Sm/Yb) ch = 2.0-2.8). A specific geochemical feature of the rocks is strong Nb, Ta, Ti, and Eu negative anomalies ((La/Nb) PM = 4.5-1.6, (La/Ta) PM = 3.2-2.0, Eu/Eu * = 0.7) and a positive U anomaly on their normalized element patterns; e{open} Nd(T) varies from +2.3 to +3.1. The HREE depletion of the Kuznetsk Basin volcanic rock points to the presence of garnet in the mantle source during their generation. The low Mg# indicates that the parental melts are not of the primary-mantle genesis but are probably the product of differentiation in deep-seated intermediate magma chambers. © 2012 Elsevier B.V.
Ключевые слова:	magma chamber; magmatic differentiation; mantle plume; mantle source; mineralogy; Permian-Triassic boundary; petrology; volcanic rock; Kuznetsk Basin; Russian Federation; Siberia; garnet; crystallization; craton; andesite; age determination; Petrology; Permo-Triassic; Mineralogy; Kuznetsk Basin; Geochemistry; geochemistry; Andesitic basalts;
Издано:	2012
Физ. характеристика:	с.334-346