Arctic Ocean gas reserves, and the Chukchi shelf forms the border between Russian and the United States as stated in the USSR–USA Maritime Boundary Agreement. The whole area is subject to international territorial claims. An underwater ridge, the Lomonosov Ridge, divides the deep sea North Polar Basin into two oceanic basins: the Eurasian Basin, which is between deep, and the Amerasian Basin (sometimes called the North American, or Hyperborean Basin), which is about deep. The bathymetry of the ocean bottom is marked by fault block ridges, abyssal plains, ocean deeps, and basins. The average depth of the Arctic Ocean is . The
Argentine Basin Antarctic Bottom Water current, which dominates the circulation in the abyssal layer of the southwest Atlantic, enters the southwest part of the Argentine Basin, then is deflected northward along the continental rise. It passes into the Brazil Basin through the Vema Channel (39° 30′ W) to the west of the Rio Grande Rise. Here, the current reaches velocities of 20–25 cm/s. Argentine Basin The Argentine Basin is a region of the Atlantic Ocean floor off the east coast of Argentina, between the Mid-Atlantic Ridge to the east and the Scotia Basin to the west. To the north is the Brazil