The Arctic Ocean margin of the North American plate in Asia forms a continental shelf up to 800 km wide, which underlies the East Siberia Sea (Fig. 1). The New Siberian Islands separate the East Siberian Sea from the Laptev Sea on the west, and Wrangel Island (Ostrov Vrangelya) separates the East Siberian Sea from the Chukchi Sea on the east. The area of the East Siberian Sea is about 1,500,000 km², and it is connected to the Chukchi Sea by Long Strait (Proliv Longa) and to the Laptev Sea by several straits through the New Siberian Islands.

The shelf of the East Siberian Sea is shallow, less than 50 m deep, and flat. The shelf is cut by two valleys, a few tens of meters deeper than the surrounding shelf, which are extensions of the Indigirka and Kolyma rivers (Naugler and others, 1974). The continental slope of the East Siberian Sea is gentle (slope ~1°), and alluvial cones spread out into the adjacent abyssal plain from submarine canyons (Lastochkin, 1980). The shelf appears to be connected to the Arlis Plateau, but is separated from the Lomonosov Ridge by a sediment-filled trough (Dementiskaya and Hunkins, 1971) (Fig. 2).

Since the geology of the East Siberian Shelf is poorly known, most tectonic and geologic models are extrapolations of the geology of the New Siberian Islands. Wrangel Island, and northern Eurasia. Rather than present the details of these speculations, in this chapter we summarize the known geology of