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The article discusses the geochronological study of the trachyrhyolites of the Ulkan Group. It states that the volcanic deposits overlie metamorphic rocks of the Early Proterozoic era. It mentions that Riphean deposit sequence is considered as Siberian hypostratotype. It adds that isochronous Rb-Sr method was used to identify the age of the crust located at the base of Lower Riphean Uyan Group. Furthermore, the chemical composition of volcanites correspond to igneous rocks while associated granites and acid volcanites correspond to granites which are A-type.

The article presents a study which discusses uranium (U)-lead (Pb) geochronological dating of Paleozoic era granitoide rock formation of the Kiviliyskii complex in the Bureya Terrane in Russia. It says that porphyroblastic granites and rare quartz diorites from the Kiviliyskii massif were used as samples, in which accessory zircon crystals were selected and were subjected to multiple removal of surface contamination with ethanol, acetone, and nitric acid (HNO3). It says that Krogh's modified procedure was used for the chemical decomposition of zircon and U and Pb separation and isotope analyses were performed with the use of the MAT 261 multicollector mass spectrometer from Finnigan Corp. Results show that the granitoides in the site have an early Paleozoic era age.

The article presents a study that investigates the age of granitoids and the ancient basement of the Western Siberian Platform. Data were gathered in an interfluve of the Elogui and Vakh rivers in the east of Western Siberian Plate and granitoids were in the alkaline granites field. Potassium-argon dating (K-Ar) of all rocks showed that Tyn'yarskii rhyolite'granite massif's age was probably Early Permian. Extraction and analysis of zircons from Samples Tyn-101/2590 meters (m) and Tyn-100/2204 m were performed. Results show that dipyramidal and molten resorbed zircon crystals in the samples had an age range of 270-280 mya (Ma). The study concludes that the basement may be ancient granite-metamorphic.