摘要 : The South Anyui Fold System was formed at the end of the Early Cretaceous at the site of a closed oceanic basin as a result of the collision of the Chukotka microcontinent with the structures of the active margin of the Siberian c... 展开 The South Anyui Fold System was formed at the end of the Early Cretaceous at the site of a closed oceanic basin as a result of the collision of the Chukotka microcontinent with the structures of the active margin of the Siberian continent. There are two distinct stages in the tectonic history of the oceanic basin. At the first stage (Late Paleozoic-Early Mesozoic), there was the Proto-Arctic Ocean, which united the South Anyui and Angayucham basins. The second stage (Volgian-Hauterivian-Barremian) began with cessation of spreading, the shortening of the oceanic basin, and accumulation of turbidites. In the west, the South Anyui Suture ends in the Khroma Loop and, like the Kolyma Loop, the suture is a package of allochthons composed of fragments of the Proto-Arctic Ocean. In the central part, the suture is the result of the collision of the Chukotka micro continent with the active margin of the Kolyma-Omolon microcontinent. The eastern end of the collisional suture is formed by ophiolites in the Matachingai River basin. The Late Triassic-Early Jurassic ensimatic island arcs of the Velmay Terrane accreted to the Chukotka microcontinent in eastern Chukotka. In this area, the Proto-Arctic Ocean connected with the Meso-Pacific Ocean, from where the island-arc terranes were transported. The South Anyui Suture is the border of the Verkhoyansk-Kolyma and Chukotka fold regions and, accordingly, the border of the Pacific and Arctic structures. There are significant differences in the tectonic evolution of these structures, which are determined by the different history and age of the Proto-Arctic and Oymyakon paleoceans, fragments of which were preserved in the Khroma and Kolyma structural loops, as well as the patterns of sedimentation on the Verkhoyansk and Chukotka passive margins, which belonged to the Siberia and Laurentia paleocontinents. 收起