Summary: | We present an atlas of paleogeographic and paleotectonic maps which documents major events in the Arctic for 0–157 Ma. We demonstrate that the Mendeleev Ridge has a continental basement. The following chronology of events in the history of the Arctic Ocean is proposed: (1) Jurassic: continental rifting in the area of the Sverdrup-Banks basins and in the area of the present-day Canada Basin; a system of continental-margin volcanic belts formed in the region of Chukotka and the Verkhoyansk-Omolon; (2) Berriasian-Barremian: formation of the continental-margin Verkhoyansk-Chukotka Orogen; fast opening of Canada Basin (~133–125 Ma); (3) Aptian-Albian: formation of continental igneous provinces, rifting and magmatism in the area of the Alpha-Mendeleev ridges; rifting in the Ust’-Lena, Anisin, North-Chukchi, Podvodnikov and Toll basins; (4) Cenomanian-Campanian: intraplate magmatism in the area of the Alpha-Mendeleev ridges; (5) Campanian-Maastrichtian: a likely start of compressional deformations in the area of the Chukchi Sea; (6) Paleocene: formation of the continental-margin orogen; continental rifting along the present-day Eurasia Basin and the Ust’-Lena Basin; (7) Early-Middle Eocene: onset of opening of the Eurasia Basin started; (8) Middle-Late Eocene: a major restructuring of paleogeography of the Arctic took place at ca. 45 Ma with subaerial emergence of the Barents and Kara Sea shelves and onset of ultra-slow spreading of the Gakkel Ridge, and start of the epoch of formation of normal and strike-slip faults on the Lomonosov and Alpha-Mendeleev ridges and on the shelves of the Chukchi and East Siberian seas. Paleoclimate is discussed in connection with changes in the paleogeography.
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