Geologicheskii Vestnik

The paper presents new data on the conditions of formation of igneous rocks in the western slope of the Southern Urals and the adjacent part of the East European platform. Calculations of P-T mantle melting parameters show that the implementation of plume process results in formation of one-type rocks (picrites and picrodolerites), but their genesis may be fundamentally different. One kind is the result of crystallization of undifferentiated mantle melt in the upper layers of the crust, while the other is formed by differentiation in large intracrustal magma chambers.

plume, magmatic melt, P-T parameters of picrites, picrodolerites, the western slope of the Southern Urals, differentiation, olivine, pyroxene geothermometer, Middle Riphean

• Alekseev A.A., Alekseeva G.V., Kovalev S.G. Rassloennye intruzii zapadnogo sklona Urala [Layered intrusions of thewestern slope of the Urals]. Ufa: Gilem, 2000. 188 p. (In Russian).
• Аlekseev А.А., Аlekseeva G.V., Kovalev S.G. Differentsirovannye intruzii zapadnogo sklona Urala [Differentiated intrusions of the western slope of the Urals]. Ufa: Gilem, 2003. 171 p. (In Russian).
• De Hoog Jan C.M., Louise G., Cornell D.H. Trace-element geochemistry of mantle olivine and application to mantle petrogenesis and geothermobarometry // Chemical Geology. 2010. V. 270. Р. 196–215. DOI: 10.1016/j.chemgeo.2009.11.017.
• Dobretsov N.L., Borisenko А.S., Izokh А.E., Zhmodik S.M. Termohimicheskaya model' permotriasovyh mantijnyh plyumov Evrazii kak osnova dlya vyyavleniya zakonomernostei formirovaniya i prognoza medno-nikelevyh, blagorodno- i redkometal'nyh mestorozhdenii [A thermochemical model of Eurasian PermoTriassic mantle plumes as a basis for prediction and exploration for Cu-Ni-PGE and rare-metal ore deposits] // Geologiya i geofizika. 2010. V. 51, No. 9. P. 1159–1187. Doi.org/10.1016/j.rgg.2010.08.002. (In Russian).
• Ernst R.E. Large Igneous Provinces. Cambridge Univ. Press, 2014. 653 p. https://doi.org/10.1017/CBO9781139025300.
• Green D.H. Primary magmas at mid-ocean ridges, ‘hotspots’ and otherintraplate settings: constraints on mantle potential temperatures // Geological Society of America. V. 388. 2005. https://doi.org/10.1130/0-8137-2388-4.217.
• Kholodnov V.V., Bocharnikova T.D., Shagalov E.S. Sostav, vozrast i genezis magnetit-il’menitovykh rud srednerifejskogo stratifitsirovannogo Medvedevskogo massiva (Kusinsko-Kopanskij kompleks YUzhnogo Urala) [Composition, age and genesis of magnetite-ilmenite ores of the Middle Riphean stratified Medvedev massif (Kusino-Kopan complex of the Southern Urals)] // Litosfera. 2012. No. 5. P. 145–165 (In Russian).
• Kovalev S.G., Puchkov V.N., Vysotskiy S.I., Kovalev S.S. Usloviya obrazovaniya magmaticheskikh porod pri plyumovom protsesse (na primere zapadnogo sklona Yuzhnogo Urala) // DAN. 2017. V. 475. No. 2. P. 171–175 (In Russian).
• Kovalev S.G., Snachev V.I., Romanovskaya M.А. Novye geologo-petrogeneticheskie aspekty formirovaniya KusinskoKopanskogo kompleksa [New geological and petrogenetic aspects of the formation of the Kusino-Copan complex] // Vestnik Moskovskogo Universiteta. Ser. 4. Geologiya. 1995. No. 4. P. 81–85 (In Russian).
• Kovalev S.G., Vysotskiy I.V., Puchkov V.N., Maslov A.V., Gareyev E.Z. Geokhimicheskaya spetsializatsiya strukturno-veshchestvennykh kompleksov Bashkirskogo megantiklinoriya [Geochemical specialization of structurally-material complexes of the Bashkir meganticlinorium]. Ufa: DizaynPress, 2013. 268 p. (In Russian).
• Loucks R.R. A precise olivine-augite Mg-Fe-exchange geothermometer // Contrib Mineral Petrol. 1996. V. 125. Р. 140–150. Doi.org/10.1007/s004100050211.
• Nosova A.A., Kargin A.V., Larionova Y.O., Sazonova L.V., Gorozhanin V.M., Kovalev S.G. Mesoproterozoic within-plate igneous province of the western urals: Main petrogenetic rock types and their origin // Petrology. 2012. V. 20. No. 4. P. 356–390. Doi.org/10.1134/s086959111204008x.
• Puchkov V.N. Geologiya Urala i Priural’ya (aktual’nye voprosy stratigrafii, tektoniki, geodinamiki i metallogenii) [Geology of the Urals and the Urals(actual issues of stratigraphy, tectonics, geodynamics and metallogeny)] Ufa: DizajnPoligrafServis, 2010. 280 p. (In Russian).
• Puchkov V.N., Bogdanova S.V., Ernst R., Kozlov V., Krasnobaev A.A., Soderlund U., Wingate M.T.D., Postnikov A.V., Sergeeva N.D. The ca. 1380 Ma Mashak igneous event of the Southern Urals // Lithos. 2013. V. 174. Р. 109–124. Doi.org/10.1016/j.lithos.2012.08.021.
• Puchkov V.N., Kovalev S.G. Plyumovye sobytiya na Urale i ikh svyaz’ s subglobal’nymi ehpokhami riftogeneza [Plume eventsin the Urals and their relationship to the subglobal epochs of rifting] // Kontinental’nyj riftogenez,soputstvuyushhie protsessy. Irkutsk: IZK SO RАN, 2013. P. 34–38 (In Russian).
• Sazonova L.V., Nosova А.А., Larionova Yu.O., Kargin А.V., Kovalev S.G. Mezoproterozojskie pikrity vostochnoj okrainy Vostochno-Evropejskoj platformy i Bashkirskogo megantiklinoriya: petrogenezis i osobennosti sostavov olivina i klinopiroksena [Mesoproterozoic picrites of the eastern margin of the East European platform and the Bashkir meganticlinorium: petrogenesis and features of the compositions of olivine and clinopyroxene] // Litosfera. 2011. No. 3. P. 64–83 (In Russian).
• Sobolev A.V., Krivolutskaya N.A., Kuzmin D.V. Petrology of the parental melts and mantle sources of Siberian trap magmatism // Petrology. 2009. V. 17, No. 3. P. 253–286. https://doi.org/10.1134/s0869591109030047.