| Реферат: | eng: The data on the chemical composition of microinclusions in zircon grains from rocks of the polygenic Berezovskii mafic-ultramafic massif (Sakhalin Island), obtained using the JEOL JXA-8100 electron probe microanalyzer, is presented. In the massif structure has a protrusion of restitogenic ultramafic rokcs, intruding its intrusion of ortomagmatic gabbros, and the two contact-reaction zones along with contact of gabbroid intrusion with ultramafic protrusion (hybrid olivine gabbro and ultramafic), and with enclosing strata (hybrid quartz-bearing gabbros and diorite). Zircons are divided into four varieties: relict, xenogenic, syngenetic, and epigenetic. Microinclusions with an apparent size of 10-20 mu m were found mainly in syngenetic zircon grains from hybrid gabbro-diorites, diorites, and quartz diorites. They are represented by more common carbonate and K-Na feldspars, as well as more rare quartz, albite, mica and unidentified phases. In isolated cases, the microinclusions of grossular, siderite and iron oxide were encountered. Microinclusions did not occur in zircon grains from ultramafic and olivine gabbroids, for which the determinations showed an ancient U-Pb isotopic age.
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