Tizard Bank

The Tizard Bank, (Filipino: Pampang ng Bayani); (Vietnamese: Cụm Nam Yết); (Chinese: 鄭和群礁; pinyin: Zhènghé Qúnjiāo), 10°15′N 114°30′E is a partially sunken atoll and one of the significant maritime features of the north-western part of the Spratly Islands. It is claimed by Vietnam, the People's Republic of China (PRC), and the Republic of China (ROC), and various parts of it are occupied by these states. It was named after Thomas Henry Tizard (1839 – 17 February 1924), a British oceanographer and surveyor who surveyed the bank from aboard HMS Rifleman in the 1860s. In 1947 the Republic of China government gave the bank the name Zheng He Archipelago after the famous Ming-era admiral, although there is no evidence that he ever visited Tizard Bank. From before the 1870s the islands were used by fishermen from Hainan with Itu Aba Island having a semi-permanent settlement of Chinese fishermen. The bank rises steeply from surrounding depths ranging from 500 to 700 metres (1,600 to 2,300 ft). It is 32.05 nautical miles (59.36 km; 36.88 mi) in length, and extends west from the Gaven Reefs to the northwest of Dangerous Ground. The atoll is up to 11.36 nautical miles (21.04 km; 13.07 mi) wide. The total area is 953 square kilometres (368 sq mi), and the greatest depth of the central lagoon is 80 metres (260 ft). The central lagoon generally is 10 to 40 metres (33 to 131 ft) deep, although many coral heads have much shallower depths. There are several entrances into the lagoon. The bank contains a number of features along the rim of the reef, including shoals, reefs, islands, and cays, numerous wrecks, some lighthouses, and an ammunition dumping ground in about 2,000 metres (6,600 ft) of water to the north of Itu Aba. Several coral heads with depths...