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
Angola Basin Angola Basin The Angola Basin is located along the West African South Atlantic Margin which extends from Cameroon to Angola. It is characterized as a passive margin that began spreading in the south and then continued upwards throughout the basin. This basin formed during the initial breakup of the supercontinent Pangaea during the early Cretaceous, creating the Atlantic Ocean and causing the formation of the Angola, Cape, and Argentine basins. It is often separated into two units: the Lower Congo Basin, which lies in the northern region and the Kwanza Basin which is in the southern part of the Angola