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Warren J. Nokleberg, U.S. Geological Survey (United States)
Leonid M. Parfenov, Russian Academy of Sciences (Russian Federation)
Christopher R. Scotese, University of Texas (United States)
Gombosuren Badarch, Mongolian Academy of Sciences (Mongolia)
Nikolai A. Berzin, Russian Academy of Sciences (Russian Federation)
Alexander I. Khanchuk, Russian Academy of Sciences (Russian Federation)
Mikhail I. Kuzmin, Russian Academy of Sciences (Russian Federation)
Alexander A. Obolenskiy, Russian Academy of Sciences (Russian Federation)
Andrei V. Prokopiev, Russian Academy of Sciences (Russian Federation)
Sergey M. Rodionov, Russian Academy of Sciences (Russian Federation)
Hongquan Yan, Jilin University (China)
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The vast, mountainous terranes of Northeast Asia hold the key to the tectonic and metal-logenic evolution of a major and geologically complicated region of the world. This region stretches from the Ural Mountains and the Arctic Islands of central Russia to the Kamchatka vol-canic arc in the Russian Far East. The region also includes northern Kazakhstan, China, Mongo-lia, the Korean Peninsula, and Japan. The tectonic development of the region is recorded in a se-ries of cratons, craton margins, oceanic plates, active rifts, and orogenic collages of the present-day Northeast Asia continent. The collages consist of tectonostratigraphic terranes that are com-posed of fragments of igneous arcs, accretionary-wedge and subduction-zone complexes, passive continental margins, and cratons. The tectonostratigraphic terranes are overlapped by continen-tal-margin-arc and sedimentary-basin assemblages. The tectonic history of cratons, craton mar-gins, oceanic plates, terranes, and overlap assemblages is complex due to extensional dispersion and translation during strike-slip faulting that occurred subparallel to continental margins.
This talk presents a series of regional tectonic time-slice maps and a computer animation that dynamically illustrate the tectonic assembly and major metallogenic events of Northeast Asia since the late Precambrian. The key events in the tectonic history of Northeast Asia are: (1) the formation of the North Asian Craton during the breakup of a late Precambrian superconti-nent; (2) during the late Precambrian and early Paleozoic, establishment of an active subduction zone along the present-day, southern margin of the North Asian Craton (Mongolian subduction zone); (3) during the late Paleozoic, closure of oceans between Siberia, Baltica, Kazakhstan, and north China; (4) during the Triassic and Jurassic, progressive closure of the Mongol-Okhotsk Ocean between Sino-Korean and the North Asian Cratons to form the core of present-day North-east Asia; (5) during the Late Jurassic through early Cenozoic, accretion of allochtonous terranes along the northern margin of the North Asian Craton, and along the margin of Eastern Asia; (6) for the first time in the early Cretaceous, formation of a continuous continental complex between the Russian Northeast and northwestern North America; and finally (7) in the Cenozoic, forma-tion of continental-margin arcs and back-arc basins along the entire Pacific-facing margin of Northeast Asia. These time-slice maps provide the basis of a preliminary dynamic tectonic and metallogenic model of Northeast Asia that as an animation provides new insights into the geo-logic, tectonic, and metallogenic evolution of this complex region.
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