Arctic ocean geophysical studies; the southern half of the Siberia Basin

In 1962, ice island Arlis II drifted over a portion of the southern half of the Siberia Basin. Depth recordings made between 81°N, 170°E and 82°30′N, 160°E show that the ocean floor in this area is an abyssal plain at about 2,825 m depth dissected by several interplain channels. This abyssal plain, here called the Wrangel Abyssal Plain, is bounded on the north by Arlis Gap, which joins it with the Siberia Abyssal Plain at about 3,946 m depth. The Siberia Abyssal Plain occupies the northern half of the Siberia Basin. Seismic reflection profiles show that a prominent subbottom basement ridge exists in the vicinity of Arlis Gap. This ridge strikes in an approximately northwest direction and appears to connect with Alpha Ridge, which bounds the Siberia Basin on the east and north, and with Lomonosov Ridge, which bounds the Siberia Basin on the west. The seismic reflection profiles also show that at least 3.5 km of subhorizontal, stratified sediments underlie Wrangel Abyssal Plain south of the ridge. Each laye...