V.YU. ZABRODIN (ITiG FEB RAS)

Main geological features and tectonic position of the Norsko-Sukhotinsky Trough (the Far East)

The Norsko-Sukhotinsky Trough, also known as the Selemdzhinsky Fold System or the Nora-Sukhotinsky Terrane, is a structural element of the Bureya Massif sedimentary cover superimposed on the Oktyabrsky (Mamynsky) and Turansky blocks. It is a northeast segment of the Dasinanling-Selemdzhinsky Fold System, which is outcropped on the continental crust of the massif. The trough occurs as small discrete roof pendants of granitoid plutons with xenoliths in them, and as small basement fragments of the Amur-Zeya Plate in the south. The trough is composed of Middle Riphean (?) through Lower Triassic stratified shallow marine, coastal, lagoonal, and continental terrigenous, carbonate and volcanic deposits, as well as intrusive rocks dated as Ordovician (and, possibly, Late Cambrian) and Mid – Late Carboniferous (Kiviliysky, Oktyabrsky, and Tyrma-Bureinsky complexes). The platform-type folding consists of simple folds replaced by multiple folds in fault zones.
Keywords: Bureya Massif, sedimentary cover, Norsko-Sukhotinsky Trough, stratigraphy, magmatism, tectonics, tectonostratigraphic systems.