Инд. авторы:	Ashchepkov I.V., Zhmodik S.M., Belyanin D.K., Kiseleva O.N., Medvedev N., Travin A.V., Yudin D.S., Karmanov N.S., Downes H.
Заглавие:	Aillikites and Alkali Ultramafic Lamprophyres of the Beloziminsky Alkaline Ultrabasic-Carbonatite Massif: Possible Origin and Relations with Ore Deposits
Библ. ссылка:	Ashchepkov I.V., Zhmodik S.M., Belyanin D.K., Kiseleva O.N., Medvedev N., Travin A.V., Yudin D.S., Karmanov N.S., Downes H. Aillikites and Alkali Ultramafic Lamprophyres of the Beloziminsky Alkaline Ultrabasic-Carbonatite Massif: Possible Origin and Relations with Ore Deposits // MINERALS. - 2020. - Vol.10. - Iss. 5. - Art.404.
Внешние системы:	DOI: 10.3390/min10050404; РИНЦ: 43304684; WoS: 000548343700019;
Реферат:	eng: The 650-621 Ma plume which impinged beneath the Siberian craton during the breakup of Rodinia caused the formation of several alkaline carbonatite massifs in craton margins of the Angara rift system. The Beloziminsky alkaline ultramafic carbonatite massif (BZM) in the Urik-Iya graben includes alnoites, phlogopite carbonatites and aillikites. The Yuzhriaya pipe (YuP) similar to 645 Ma and the 640-621 Ma aillikites in BZM, dated by Ar-40/Ar-39, contain xenoliths of carbonated sulfide-bearing dunites, xenocrysts of olivines, Cr-diopsides, Cr-phlogopites, Cr-spinels (P similar to 4-2 GPa and T similar to 800-1250 degrees C) and xenocrysts of augites with elevated HFSE, U, Th. Al-augites and kaersutites fractionated from T similar to 1100-700 degrees C along the 90 mW/m(2) geotherm. Higher T trend for Al-Ti augite, pargasites, Ti-biotites series (0.4-1.5 GPa) relate to intermediate magma chambers near the Moho and in the crust. Silicate xenocrysts show Zr-Hf, Ta-Nb peaks and correspond to carbonate-rich magma fractionation that possibly supplied the massif. Aillikites contain olivines, rare Cr-diopsides and oxides. The serpentinites are barren, fragments of ore-bearing Phl carbonatites contain perovskites, Ta-niobates, zircons, thorites, polymetallic sulphides and Ta-Mn-Nb-rich magnetites, ilmenites and Ta-Nb oxides. The aillikites are divided by bulk rock and trace elements into seven groups with varying HFSE and LILE due to different incorporation of carbonatites and related rocks. Apatites and perovskites reveal remarkably high LREE levels. Aillikites were generated by 1-0.5% melting of the highly metasomatized mantle with ilmenite, perovskite apatite, sulfides and mica, enriched by subduction-related melts and fluids rich in LILE and HFSE. Additional silicate crystal fractionation increased the trace element concentrations. The carbonate-silicate P-bearing magmas may have produced the concentration of the ore components and HFSE in the essentially carbonatitic melts after liquid immiscibility in the final stage. The mechanical enrichment of aillikites in ore and trace element-bearing minerals was due to mixture with captured solid carbonatites after intrusion in the massif.
Ключевые слова:	TRACE-ELEMENT; SIBERIAN CRATON; COMPLEX; SULFATE MELTS; RUSSIA IMPLICATIONS; LIQUID IMMISCIBILITY; LITHOSPHERIC MANTLE BENEATH; EASTERN SAYAN; plume; subduction; metasomatism; rare metals; mantle; carbonatite aillikites; PARTITION-COEFFICIENTS; HF-PB ISOTOPE;
Издано:	2020
Физ. характеристика:	404