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Address : U.S. Geological Survey, United States;Pacific Rim Geological Consulting, Fairbanks, United States;University of Texas,, United States;
Celebration date : 20 Saturday September 2008
Author name : Nokleberg, Warren J.1; Bundtzen, Thomas K.2; Scotese, Christopher R.3; Parfenov, Leonid M.4; Monger , James W.H.5; Dawson, Kenneth M.5; Khanchuk, Alexander I.4; Goryachev , Nikolai A.4; Shpikerman, Vladimir I.4

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  • Article title : Metallogenic and tectonic model for the Circum-North Pacific
    Article type : Tectonic & Seismotectonic
    Location : International Geological Congress,oslo 2008

    Fulltext :

    The Phanerozoic metallogenic and tectonic evolution of the Circum-North Pacific (Russian Far East, Alaska, and the Canadian Cordillera) is recorded in the cratons, craton margins, and orogenic collages of the Circum-North Pacific mountain belts that separate the North Pacific from the eastern North Asian and western North American Cratons. The collages consist of tectonostratigraphic terranes with older metallogenic belts that are composed of fragments of igneous arcs, accretionary-wedge and subduction-zone complexes, passive continental margins, and cratons; they are overlapped by continental-margin-arc and sedimentary-basin assemblages with younger metallogenic belts. The metallogenic and geologic history of terranes, overlap assemblages, cratons, and craton margins is highly complicated because of post-accretion dismemberment and translation during strike-slip faulting that occurred subparallel to continental margins. Six processes overlapping in time were responsible for most metallogenic and geologic complexities of the region. (1) In the Late Proterozoic, Late Devonian, and Early Carboniferous, major periods of rifting occurred along the ancestral margins of present-day Northeast Asia and northwestern North American. (2) From about the Late Triassic through the mid-Cretaceous, a succession of island arcs and contained igneous-arc-related metallogenic belts, and tectonically paired subduction zones formed near continental margins. (3) From about mainly the mid-Cretaceous through the present, a succession of igneous arcs and contained metallogenic belts, and tectonically paired subduction zones formed along the continental margins. (4) From about the Jurassic to the present, oblique convergence and rotations caused orogen-parallel sinistral, and then dextral displacements within the upper plate margins of cratons that have become Northeast Asia and the North America. (5) From the Early Jurassic through Tertiary, movement of the upper continental plates toward subduction zones resulted in strong plate coupling and accretion of the former island arcs, subduction zones, and contained metallogenic belts to continental margins. (6) In the middle and late Cenozoic, oblique to orthogonal convergence of the Pacific Plate with present-day Alaska and Northeast Asia resulted in formation of the modern-day ring of volcanoes and contained metallogenic belts around the Circum-North Pacific. To illustrate the Phanerozoic metallogenic and tectonic evolution of the Circum-North Pacific, dynamic computer animation with successive time-stage diagrams for the region is constructed to portray the formation of metallogenic belts and associated tectonic events through geologic space and time.