Johnson South Reef Johnson South Reef Johnson South Reef (; ), also known as Chigua Reef in China, Gạc Ma Reef in Vietnam and Mabini Reef in the Philippines is a reef in the southwest portion of the Union Banks in the Spratly Islands of the South China Sea. It is controlled by the People's Republic of China (PRC), but its ownership is disputed by the PRC, the Philippines, Taiwan, and Vietnam. Johnson South Reef lies adjacent to the Vietnamese-controlled Collins Reef (also known as Johnson North Reef) which lies to the northwest. It is naturally above water only at low tide. Prior
Kenn Reef 500 km to the southwest. Kenn Reef is part of a submerged continental block, called the Kenn Plateau. The Kenn Plateau lies off the north eastern Australian coast and is a region characterised by a series of prominent, bathymetric troughs and marginal plateaux. And is submerged by 1000 m to over 3000 m of water. The Kenn Plateau, covers around 100,000 km², an area larger than the Tasmanian landmass. Various islands and reefs, whose origin is thought to be related to the Tasmantid Seamount Chain, lie along the western margin of the Kenn Plateau and include the well known Kenn