submarine basin of the southern Arabian Sea, rising to meet the submerged Carlsberg Ridge to the south, the Maldive Islands to the southeast, India and Pakistan to the northeast, Iran to the north, and the Arabian Peninsula to the west. It has a maximum depth of 19,275 feet (5,875 metres) and is separated by the Carlsberg Ridge from the deeper Somali Basin to the south and west. The sill depth between the Arabian and Somali basins is about 9,800 feet (3,000 metres). The floor of the basin, except along the southeastern edge, is covered by sediment deposited by the Indus River in the form of a great alluvial fan—the Indus Cone—whose thickness diminishes to the south.