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Field, seismic, structural, and stratigraphic data were used to reconstruct the geologic history of the Arctic in 10 m.y. time slices from the present to mid-Jurassic--the time of initial opening of the Arctic Ocean. A basic assumption used for the reconstruction is that Lomonosov Ridge, Alpha Ridge, Mendeleyev Ridge, and Chukchi Plateau are all foundered continental plates.
Opening of the Arctic occurred in 2 stages: Late Jurassic-Cretaceous for the Canada basin, and Neogene for the Eurasian basin. Opening was facilitated by 2 subparallel transform shears: the Arctic (Kaltag-Porcupine) on the east and the Chukchi on the west. Deformation was essentially tensional on the Barents side of the Arctic, and shear-compressional on the Alaska side.
The development of Chukotsk, the North Slope, Brooks, Range, northwestern Canada, Seward Peninsula, and central Alaska can be sequentially related to Arctic opening, modified by impingement of allochthonous terranes (the Pacific plates of Tintina, Denali, Orca, Anadyr, Khatyrka, Kolyma) arriving from the south.
The North Slope of Alaska--a passive, rifted, subsided margin--was aligned with a similar margin on Alpha Ridge. Northeastern Alaska (the Romanzoff Mountain area) lined up opposite the north end of the Sverdrup Rim, near Prince Patrick and Borden Islands.
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