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This paper presents the results of Sm-Nd isotopic-geochemical and U-Pb geochronological studies of metamorphic (Ilikan Sequence) and associated igneous rocks from the Ilikan lithotectonic zone (terrane) located in the Dzhugdzhur-Stanovoi Superterrane from the Central Asian Foldbelt. The Nd model age, T Nd(DM), of metamorphic rocks from the Ilikan Sequence is 2.6–3.2 Ga pointing to the likelihood that the lower boundary of their protolith formation probably does not exceed 2.6 Ga. The age of detrital zircons from metasedimentary rocks of the Ilikan Sequence is 2700–2900 Ma, which absolutely agrees with Sm-Nd isotopic-geochemical results. The U-Pb zircon age of metagabbro that intruded the rocks of the Ilikan Sequence and underwent high-temperature amphibolite metamophism with subsequent structural transformations is 2635 ± 4 Ma. The obtained results allow us to conclude that the age of the Ilikan Sequence is 2630–2700 Ma. All this gives grounds to state that the Dzhugdzhur-Stanovoi Superterrane in the Central Asian Foldbelt was formed due to amalgamation of non-Siberian terranes as is assumed for the Argun, Bureya, and Mamynskii terranes of the Amur Superterrane from the Central Asian Foldbelt.  相似文献   
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Izvestiya, Physics of the Solid Earth - Abstract—Based on the common-mid-point (CMP) seismic data on the 3-DV reference profile, using dynamic conversion of refracted waves into time...  相似文献   
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The Hercynian mobile belts in Central Asia comprise the Hercynian proper and the Late Hercynian (Indosinian) belts separated by the South Gobi microcontinent, the origin of which is related to the evolution of the South Mongolian and Inner Mongolian basins with the oceanic crust. Crystalline complexes within these belts occur as tectonic sheets of a variety of sizes. At the early stages, the metamorphic grade of these complexes reached conditions of high-temperature subfacies of amphibolite and locally developed granulite facies. In tectonic terms, the Hercynian belt of metamorphic rocks is situated at the margin of the North Asian Caledonian continent and extends from the southeast to the northwest along the southern slope of the Gobi, Mongolian, and Chinese Altai to East Kazakhstan, where metamorphic rocks are localized in the Irtysh Shear Zone. All these rocks are combined into the South Altai metamorphic belt of more than 1500 km in extent. Another belt of isolated outcrops of crystalline rocks conventionally combined into the Indosinian South Gobi metamorphic belt is traced along the junction of the Hercynides with the South Gobi microcontinent. The high-grade metamorphic rocks within both belts are not fragments of an ensialic Caledonian or older basement. These rocks were formed 390–360 and 230–220 Ma ago as a result of the closure of the Tethian South Mongolian and Inner Mongolian oceanic basins (Paleotethys I and Paleotethys II). The spatial position of the South Altai and South Gobi metamorphic belts is caused by the asymmetric structure of the Tethian basins, where active continental margins are expressed most distinctly along their northern parts, while passive margins extend along the southern parts (in present-day coordinates).  相似文献   
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