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The Komsomolsk tin-ore district is located along the Miao-Chan Ridge in the Middle Amur River area (Khabarovsk krai) within the Badzhal accretionary terrane of the Sikhote-Alin orogenic belt. This work presents new results of U–Pb zircon dating of tonalite from the Miao-Chan complex of the Silinka granite pluton (99.7 ± 1.1 Ma) and rhyolites of the lower part of the Kholdami Formation (98.4 ± 1.0 and 98.7 ± 1.2 Ma) from the northeastern part of the Komsomolsk district. The geochemical characteristics of the rocks studied show that granitoids of the Miao-Chan complex are I-type rocks and that synchronous rhyolites of the Kholdami Formation are highly aluminous and correspond to S-type rocks. New data on the composition and early Cenomanian age of the rocks make it possible to consider the ore-magmatic system of the Komsomolsk ore district as part of the previously identified Albian–Cenomanian igneous province of Pacific Asia. [ABSTRACT FROM AUTHOR]

The first results of the geochronological dating of the specific sill-like gabbrodiorite–granodiorite intrusive bodies within the areal extent of the Paleoproterozoic Ladoga complex, singled out at an early stage of the tectono–metamorphic evolution of the Svecofennides in the southeastern part of the Fennoscandian Shield are presented. Their affinity to the fold-and-thrust paragenetic assemblage of the Meyeri zone, which separates the northern and southern domains of the Ladoga region, in the shape of plated or tabular-like magmatic bodies that fill the feather joints of low-angle thrust faults, is shown. The results of zircon dating by two technologies of the U–Pb method, indicating the time span of the early kinematic stage of the Svecofennian tectogenesis and the according plutonic igneous and metamorphic events at ca. 1.87 Ga, as well as the time limit of the imprinted folding event of the second deformation stage at about 1.83 Ga, are compared. [ABSTRACT FROM AUTHOR]

The study of granites in the basement of the Western Siberian platform is highly relevant since they are associated with hydrocarbon deposits, which are located not only above the granite massif, but also within the metasomatically altered upper layer of granites. At the same time, granites are most easily and reliably dated by zircon, which makes the geological structure of the area easier to examine, especially when the latter is overlapped by a thick sedimentary cover. The composition of granitoids from the basement of the Traigorod–Kondakovskii licensed site of the Western Siberian megabasin, located in the northwestern part of Tomsk Region, near the border with the Khanty-Mansi Autonomous Okrug, about 40 km east of the village of Aleksandrovskoye, has been studied. This license area is located within the Aleksandrovskii arch, which is bounded by the Ust-Tymsk Depression in the southeast and the Koltogorskii Trough in the northwest. The Aleksandrovskii Arch has a complex structure, which includes the large Krivolutskii granite batholith enclosed in the Carboniferous–Devonian sedimentary (mainly carbonate) rocks and Ordovician–Silurian shales. It has been established that batholith rocks are leucogranites and granites of normal alkalinity and have undergone metasomatic alterations in the form of propylitization and argillization. Granites belong to the I-type and were probably formed from the island arc substrate. Their age, according to the results of U–Pb zircon dating, is approximately 268 Ma; i.e., the generation and intrusion of granites took place during the beginning of the formation of the Koltogorsk–Urengoi Rift, the central rift of Western Siberia (which, according to Ar–Ar basalt dating, was also formed 268 million years ago). [ABSTRACT FROM AUTHOR]

The U-Pb dating of zircons from the Mazara granite massif (Southern Urals) by means of the SHRIMP II technique resulted in the conclusion that the zircons were constituted of two key generations belonging, respectively, to the substrate and to the intrusion proper. The age of the granite substrate presented by zircon cores is estimated at 1527-1548 Ma; the final stage of the substrate evolution is characterized by a concordant date of 1388 ± 16 Ma. The latter estimate is much closer to the Mesoproterosoic stage of magmatism. The information on the formation of granites of the Mazara intrusion is mainly contained in the outer parts of the crystals, with two stages distinguished within the formation history. The early and final stages are determined by the datings of 746.6 ± 24.3 and 709.1 ± 5.2 Ma, respectively (both estimates conform to the Neoproterozoic). [ABSTRACT FROM AUTHOR]

This paper presents the U-Pb zircon age of pulaskite of the main phase (294 ± 1 Ma) and the rare metal syenite (283 ± 8 Ma) of the Burpala alkaline pluton. The geochronological data show that it was formed in the Early Permian. By age, it is comparable with the Synnyr pluton of the Synnyr rift zone, alkaline granitic rocks and bimodal volcanic associations of the Uda-Vitim rift zone, and carbonatites of the Saizhen rift zone of the Central Asian foldbelt. These intraplate igneous complexes were formed almost simultaneously with crustal granitic rocks of the Angara-Vitim batholite. All of this gives ground to suppose that the origination of their parental melts is a result of the influence of the mantle hot spot or mantle plume on the lithosphere that led to extensive crustal anatexis. [ABSTRACT FROM AUTHOR]

The article focuses on the study on which aims to determine the Riphean age of zircons from alkaline syenites of the Karsakpai massif of South Ulutau in Central Kazakhstan with the uranium-lead (U-Pb) method. It mentions that the granitoids varying in chemical composition associated with Precambrian metamorphic strata were considered as coarse-grained gneissic granites (Zhaunkarskii complex), porphyroblastic granite-gneisses, and sub-alkaline potassic granites (Aktas complex). It states that the characteristics features of syenites of the Karsakpai granites and massif of the Aktas complex are massive structures and an absence of metamorphic transformations. Furthermore, it says that the age of intrusion of the massif allows to consider more ancient metamorphic complexes as Pre-Riphean.

The article presents a study on the lutetium-hafnium (Lu-Hf) and uranium-lead (U-Pb) isotope systems with concepts of geochemical evolution of the crust of the Earth. It says that the study used zircon U-Pb dating for verification due to the material's low sensitivity to greisenization. It discusses the analysis of the age ranges between lithium-fluorine (Li-F) formation, which was characterized by monzonitoids intrusions. It adds that the data obtained show that Li-F granites from the Far East are the youngest in Eurasia.