Salvage operations on a sunken Southern Song Dynasty (1127-1279)
ship started Thursday as a specially designed steel structure was
lowered into the sea at about 12 a.m. near Yangjiang, in south
China's
Guangdong Province.
The rectangular structure was pulled by a 900-ton tug to a
position just above the ill-fated ship. At 11:45 AM., it was
released and began to slowly sink.
Weighing 530 tons, the double-box structure is 35.7 meters long,
14.4 meters wide and 12 meters high. It took engineers from
Guangzhou Salvage Bureau more than a month to make.
The engineers have filled the gaps between the two steel boxes
with sand, in order to increase the weight of the steel structure
and cope with the effect of gravity under static pressure.
A score of frogmen assisted with underwater operations on
Thursday. The sunken ship is expected to be hoisted out of the
seawater in July.
According to the salvage plan, the upper part of the steel
structure will be brought out of the seawater together with the
sunken ship, while the lower part will stay on the seabed forever,
said Wu Jiancheng, who is in charge of the salvage operation.
Experts spent three years planning the salvage, considered to be
a world first for underwater archaeology.
Archaeologists normally excavate the relics on the sunken boat
first and then salvage the boat.
The sunken ship was found accidentally in 1987 by Guangzhou
Salvage Bureau and a British underwater salvage company. The first
ancient vessel to be discovered on the "Marine Silk Road" in the
South China Sea, it was named "Nanhai No.1," meaning South China
Sea No.1.
The ship is located some 30 nautical miles west of Hailing
Island of Yangjiang City, and lies at a depth of more than 20
meters. About 30 meters long, the vessel is the largest Song
Dynasty cargo ship ever discovered.
Archaeologists estimate that there are probably 60,000 to 80,000
relics on the sunken ship.
It is believed that a successful salvage of the sunken ship will
offer important material evidence for restoring the "Silk Road on
the Sea," and for the study of China's history in seafaring, ship
building, and ceramics making.
According to Wu, workers have cleared away 25 tons of silt
around the sunken ship and have brought out of the seawater 390
cultural relic items. They include green glazed porcelain plates,
tin pots and shadowy blue porcelain objects.
(Xinhua News Agency May 18, 2007)
