Инд. авторы:	Sklyarov E.V., Lavrenchuk A.V., Fedorovsky V.S., Gladkochub D.P., Donskaya T.V., Kotov A.B., Mazukabzov A.M., Starikova A.E.
Заглавие:	Regional, Contact Metamorphism, and Autometamorphism of the Olkhon Terrane (West Baikal Area)
Библ. ссылка:	Sklyarov E.V., Lavrenchuk A.V., Fedorovsky V.S., Gladkochub D.P., Donskaya T.V., Kotov A.B., Mazukabzov A.M., Starikova A.E. Regional, Contact Metamorphism, and Autometamorphism of the Olkhon Terrane (West Baikal Area) // Petrology. - 2020. - Vol.28. - Iss. 1. - P.47-61. - ISSN 0869-5911. - EISSN 1556-2085.
Внешние системы:	DOI: 10.1134/S0869591120010051; WoS: 000523026700003;
Реферат:	eng: The rocks of the Olkhon terrane experienced high-grade regional metamorphism reaching granulite facies. In addition to regional metamorphism, they were subjected to contact metamorphism and autometamorphism (mafic dikes). Three types of regional metamorphism have been distinguished. A terrane collage north of the Orso Zone revealed two stages of regional metamorphism: early-stage granulite metamorphism (T = 750-900 degrees C, P = 8-9 kbar, around 500 Ma) and late-stage amphibolite and low-amphibolite facies (T = 550-710 degrees C, P = 4-6 kbar, 460-470 Ma). The Orso microterrane separating the Krestovsky island-arc subterrane from a collage of other microterranes contains high-pressure mineral assemblages (up to 10 kbar), which are characterized by the presence of high-calcium garnet in metapelites. The Orso microterrane and Krestovsky subterrane are characterized by relatively high-pressure path of metamorphism. An extended zone of contact high-temperature metamorphism related to the emplacement of gabbro of the second phase of the Ustkrestovsky Complex has been mapped in the Krestovsky subterrane. The temperature of formation of two-pyroxene hornfels after metaporphyrites of the Birkhin volcanoplutonic association is estimated at 750-850 degrees C. Beerbachites were formed by autometamorphism of subvolcanic mafic bodies, which compose the northern part of the Tazheran composite massif (syenite, Ne-syenite, subalkaline gabbro), dikes in the Birkhin gabbro massif, as well as dikes and separate blocks in marble melange. The temperature of autometamorphism during formation of beerbachites is estimated from two-pyroxene geothermometer as 700-1000 degrees C.
Ключевые слова:	THERMOMETRY; MA; ROCKS; LAKE BAIKAL; ORTHO-PYROXENE; MARGIN; Olkhon terrane; beerbachite; hornfels; metamorphism; West Baikal Area; PARAMETERS;
Издано:	2020
Физ. характеристика:	с.47-61