The Formation Age of Pegmatites of the Mama Mica Belt: New U–Pb (ID-TIMS) Data on Zircons

Doklady Earth Sciences - New geochronological (U–Pb ID-TIMS) data on zircons from pegmatites of the Mama mica belt in the Baikal Highlands are presented. The ages obtained for the plagioclase...     

U–Pb (CA-ID-TIMS) Geochronological Studies of High-Uranium Metamict Zircons

Doklady Earth Sciences - The principal possibility of using high-uranium metamict zircon with a high self-irradiation α-dose for U–Pb geochronological studies (ID-TIMS) is demonstrated....     

Age and Tectonic Setting of Granitoids of the Uda Complex of the Dzhugdzhur Block of the Stanovoy Suture: New Data on the Formation of Giant Magmatic Belts in Eastern Asia

Doklady Earth Sciences - Granitoids of the Uda complex are distributed within the southeastern marginal part of the Siberian craton and its folded framing. Geochemical, isotope (Nd, Sr), and...     

The Upper Age Boundary of the Formation of the Olondo Fragment of the Tokko–Khani Greenstone Belt,Aldan Shield: U–Pb (ID-TIMS) Geochronological Data

Doklady Earth Sciences - This work presents new U–Pb ID-TIMS geochronological data obtained for the rocks of the metagabbro–diorite–tonalite complex of the Olondo fragment of the...     

Age and Thermal History of Eclogites from Tulepsai Complex,Eastern Mugodzhar Range (Western Kazakhstan)

Doklady Earth Sciences - Lenses of eclogites (the Tulepsai complex) that formed at the peak of metamorphism at P = 15 kbar and T = 700–750°C and experienced decompression at 12 kbar...     

Early paleozoic granitoids in the Lesser Khingan terrane, Central Asian Foldbelt: Age, geochemistry, and geodynamic interpretations

The U-Pb zircon dates obtained for the Sutara (480 ± 4 Ma), Kabalinskii (471 ± 10 Ma), and Durilovskii (461 ± 5 Ma) massifs reliably confirm an Early Proterozoic orogenic event, which took place after granulite metamorphism at approximately 500 Ma (Wilde et al., 2003) in the Lesser Khingan (Jiamusi) terrane. The rocks emplaced most shortly after the main metamorphic event are the granites of the Sutara Massif and leucogranites of the Kabalinskii Massif, whose geochemistry is close to that of collision granites. The quartz diorites and subalkaline granites of the Durilovskii Massif, whose geochemistry suggests their origin in a postcollision environment with the participation of an enriched mantle source, were emplaced longer after metamorphic event and after the aforementioned massifs.     

Age and Sources of Metasandstone of the Chiney Subgroup (Udokan Group,Aldan Shield): Results of U–Th–Pb Geochronological (LA–ICP–MS) and Nd Isotope Study

Results of U–Th–Pb LA–ICP–MS analysis of detrital zircons from metasandstones of the Chiney Subgroup (Udokan Group, Aldan Shield) have been obtained. It has been revealed that rocks of the Paleoproterozoic (about 1.90, 1.98, and 2.50 Ga) and Neoarchean (2.55 and 2.72 Ga) were their provenance sources. Deposition of the Chiney Subgroup occurred in the interval 1.87–1.90 Ga and was separated in time from the accumulation of the Kodar Subgroup siliciclastics (2.1–2.3 Ga).     

The Younger Age Limit of Metasedimentary Protolith Formation of the Lower Part of the Udokan Group Rocks (Aldan Shield)

Biotite plagiogranite intruding sediments of the Kodar Sub-Group of the Udokan Group that have both undergone amphibolite grade alterations has been dated by the U–Pb ID TIMS technique using zircon to 2105 ± 6 Ma. This age estimate to a first approximation corresponds to the younger age limit of deposition of the siliciclastics in the lower section of the Udokan Group.