A major breakthrough has been made in underwater archaeology on the mainland, and the overall salvage of the "Yangtze River Estuary No. 2" ancient ship has started——
"Carry" the century-old ship out of the water
Guangming Daily reporter Yan Weiqi
The "Yangtze River Estuary No. 2" ancient ship, which has been sleeping for about 150 years, is about to surface and lift the mystery - on March 2, on the "Power" ship of the Shanghai Salvage Bureau of the Ministry of Transport docked at waigaoqiao wharf, the "Yangtze River Estuary No. 2" ancient ship archaeology and cultural relics protection project was officially launched.
Since it was first discovered in 2015, archaeologists and scientific and technological workers have carried out nearly 8 years of meticulous underwater archaeological work around the "Yangtze River Estuary No. 2" and formulated a set of scientific, safe and efficient overall salvage programs. This will be the world's largest ancient ship archaeology and cultural relics protection project so far, and it is also the world's first archaeological excavation, overall relocation, cultural relics protection and museum construction at the same time as the implementation of archaeology and cultural relics protection projects, so it has attracted much attention.
What is the value of the "Yangtze River Estuary No. 2" ancient ship? How is the overall salvage and migration plan determined? What technical difficulties need to be broken through in the meantime? Why did the overall salvage start nearly 8 years after the discovery of the ancient ship? After the ancient ship comes out of the water, how to carry out follow-up protection and utilization? With these questions in mind, the reporter conducted an interview at the salvage site.
Discover the "Underwater Treasures"
"For a long time, the muddy water environment has been the bottleneck of China's underwater archaeology development, and the waters of the Yangtze River estuary in Shanghai are particularly prominent." Zhai Yang, deputy director of the Shanghai Cultural Relics Protection and Research Center, told reporters. To this end, the Shanghai Municipal Bureau of Cultural Heritage organized researchers from the Shanghai Cultural Relics Protection Research Center, Shanghai University, the National Underwater Cultural Heritage Protection Ningbo Base and other institutions to carry out joint research, independently developed the "Muddy Waters Underwater Imaging Device" that won the national patent, and developed the "Key Technology and Application of Robot Underwater Archaeological Equipment" that won the second prize of the Shanghai Science and Technology Award. Marine geophysical surveying equipment such as unmanned boats, multi-beam, side-sweep sonar, shallow stratigraph profiler and magnetometer were comprehensively used to carry out underwater joint surveys of the waters of the Yangtze River estuary.
Ancient ship out of the water artifacts. Courtesy of Shanghai Municipal Bureau of Cultural Heritage
In 2015, when the Shanghai Municipal Bureau of Cultural Relics organized the Shanghai Municipal Cultural Relics Protection and Research Center to carry out a key underwater archaeological survey in the Chongming Hengsha waters at the mouth of the Yangtze River, a relatively well-preserved iron shipwreck was found through sonar scanning and other technologies, and the archaeological number was "Yangtze River Estuary No. 1". After diving exploration, it was confirmed that the wreck was an iron warship of the Republic of China period. Subsequently, archaeologists expanded the scope of surveying and exploration, and found another large and well-preserved wooden ancient shipwreck in the north of the shipwreck, the archaeological number is "Yangtze River Estuary No. 2". Since then, the prelude to decoding the "Yangtze River Estuary No. 2" ancient ship has been opened.
Li Qun, vice minister of culture and tourism and director of the State Administration of Cultural Heritage, said that the newly revised "Regulations of the People's Republic of China on the Protection of Underwater Cultural Relics" will be implemented soon, and the archaeological and cultural relics protection work of the "Yangtze River Estuary No. 2" ancient ship marks a major breakthrough in underwater archaeology on the mainland and will contribute Chinese technology, Chinese experience and Chinese solutions to the world's underwater archaeology.
Ancient ships are waiting for people to decode
The "Yangtze River Estuary No. 2" ancient ship is another milestone major discovery in China's underwater archaeology after the wreck of the "Nanhai No. 1" ship of the Song Dynasty in Guangdong Province discovered 35 years ago.
The "Nanhai No. 1" is about 24 meters long and has more than 180,000 cultural relics. The "Yangtze River Estuary No. 2" ancient ship is larger than the "Nanhai No. 1", and is one of the ancient wooden shipwrecks with the largest volume, the most complete preservation and a huge number of shipboard cultural relics found in China and even in the world, and has extremely important historical, scientific and artistic value.
Zhai Yang still can't forget the excitement when he first learned that the ancient ship "Yangtze River Estuary No. 2" was discovered. Further investigation of the hull and its surroundings has made underwater archaeologists look forward to the moment when the ancient ship as a whole comes out of the water.
On March 2, the launching ceremony of the salvage of the "Yangtze River Estuary No. 2" ancient ship was held at the Waigaoqiao Wharf in Shanghai. Xinhua News Agency
"The ancient ship is a precious 'time capsule', containing a large amount of social, economic, natural, humanities and other information at that time, which has scientific value for the study of shipbuilding history, science and technology history, maritime communication history, ceramic history, economic history and other disciplines." Zhai Yang told reporters that from the current survey situation, the ancient ship type is suspected to be a flat-bottomed sand boat widely used in Shanghai water transportation during the Ming and Qing dynasties. The length of the ancient ship is about 38.5 meters, the width of the ship is about 7.8 meters, and 31 cabins have been discovered. The upper part of the wreck has a complete structure, such as the pointed bow, pile, main mast, left and right sides, and upper deck. By selecting 4 of the cabins before and after the small-scale cleaning, it was found that there were cultural relics such as Jingdezhen kiln porcelain stacked neatly in the cabin.
A large number of artifacts such as purple sand ware, Hookah jars from Vietnam, fragments of wooden buckets, masts, large hardwood ship timber, iron anchors, brown cables, pulleys, metal drill bits, drill pipes and black minerals have also been unearthed in and around the hull. From July to September 2021, the Shanghai Municipal Bureau of Cultural Heritage once again organized professional institutions to conduct underwater surveys of the ancient ship and its surroundings, and cleaned up large-scale whole vessels such as Yuan Dynasty porcelain and 60 cm high complete bean blue glaze blue and white vases that had not been found in previous surveys. In particular, the "Tongzhi Year System" section of the bottom book of some of the water porcelain in the ancient ships provides an important basis for the ancient ships to break the generation.
Experts believe that the "Yangtze River Estuary No. 2" ancient ship fills the gap for the discovery of large wooden shipwrecks in this historical period of the mainland, and also provides further empirical evidence for the study of the "Maritime Silk Road" and the "Golden Waterway" of the Yangtze River.
"This is a physical testimony of modern Shanghai as a trade and shipping center in East Asia and even the world and an important node of the 'Belt and Road'." The "Great Discovery of Underwater Archaeology" of Yangtze River Estuary No. 2 has extended the historical axis for us, enhanced the credibility of history, enriched the historical connotation, and activated the historical scene. Fang Shizhong, director of the Shanghai Municipal Bureau of Culture and Tourism and director of the Shanghai Municipal Bureau of Cultural Heritage, said.
The ancient ship will be salvaged in an integral "wrapping"
With the ancient vessel found under the water with almost zero visibility, the next question is how to salvage it to maximize the protection of this precious underwater cultural heritage?
According to experts, underwater archaeological surveys in recent years have shown that the "Yangtze River Estuary No. 2" ancient ship has been seriously washed by the current, especially with the change of the flow direction of the Yangtze River estuary, the riverbed has changed from silt to rapid downward cutting, resulting in the acceleration of the ancient ship to expose the surface of the riverbed, and the hull is facing a serious safety threat.
The ancient ship "out of the water" is imminent. At present, there are three main ways of salvage of global underwater shipwreck archaeology: one is to extract the cultural relics on the ship and dismantle and salvage the shipwreck; the second is to use the cofferdam to pump water for archaeological excavation and then salvage the shipwreck; the third is the special caisson to salvage the shipwreck, cultural relics and the surrounding seawater and sediment in accordance with the original state of one-time suspension and transportation.
Due to the extremely high turbidity of the estuary of the Yangtze River, the underwater visibility is almost zero, and the working time of the flat tide is very short, it is impossible to complete the scientific underwater archaeological mapping and photography operations; the time and cost of underwater archaeology and the construction of the cofferdam are huge, and the archaeology after the cofferdam will obstruct the waterway for a long time. The overall salvage can migrate the shipwreck in the shortest time, the lowest cost, and the greatest retention of historical information.
In view of the particularity of the "Yangtze River Estuary No. 2" ancient ship and its surrounding environment, the Shanghai Municipal Bureau of Cultural Relics and the Shanghai Salvage Bureau of the Ministry of Transport and other professional institutions have carried out research. Zhou Dongrong, deputy director of the Shanghai Salvage Bureau of the Ministry of Transport, said that due to the high sediment content and fast water flow speed at the mouth of the Yangtze River, it is impossible to use the salvage method of the "Nanhai No. 1" sectional caisson - that is, the caisson is inserted into the shipwreck, and the bottom is dug and the steel beam is hoisted. To this end, the Shanghai Salvage Bureau of the Ministry of Transport organized a team to carry out joint research and pioneered the overall migration technology of non-contact cultural relics of curved beams. In January this year, the Shanghai Salvage Bureau has used the technology to successfully complete the offshore equal proportion salvage test.
After the official salvage started, 22 giant "arc beams" will be driven by the top-entry transmitter frame, forming a huge arc-shaped caisson at the bottom of the "Yangtze River Estuary No. 2" ancient ship, the caisson is 51 meters long, 19 meters wide and 9 meters high, which can wrap the "Yangtze River Estuary No. 2" ancient ship and its attached thick sediment and seawater "without leaking", plus the weight of the salvage equipment itself, the total weight of the caisson is nearly 10,000 tons.
Zhou Dongrong told reporters that the overall salvage combines the nuclear power arc beam processing technology, the tunnel shield boring process, and the immersed tube tunnel docking process. This salvage is also the first time that these high-tech technologies have been applied to the field of cultural relics protection and archaeology, realizing the integration and development of cultural relics protection and scientific and technological innovation.
After the caisson came out of the water, in order to escort the ancient ship to the Huangpu Riverside storage site, the Shanghai Salvage Bureau also tailored a "central opening" engineering ship, and the caisson could be tightly embedded in its open middle. Subsequently, the engineering ship will "embrace" the ancient ship to the destination. According to the plan, the "Yangtze River Estuary No. 2" ancient ship is expected to complete the salvage and relocation tasks by the end of 2022.
Let the ancient ship archaeology become a public science popularization
The underwater archaeological work of "Yangtze River Estuary No. 2" has made key technological breakthroughs and achievements in the environment of zero visibility, which provides a new method for underwater archaeological research in complex muddy waters along the estuary coast, opens up new ideas, sets a new benchmark for the world's muddy underwater archaeological technology, and becomes one of the important symbols of China's underwater archaeology entering the world-class level.
What is more expected is that the "Yangtze River Estuary No. 2" ancient ship archaeology will also become the world's first ancient ship archaeological excavation, overall migration, cultural relics protection and museum construction and display project at the same time.
The preservation of the "Yangtze River Estuary No. 2" ancient ship is extremely complete, and the number of cultural relics on board is large, which is enough to support the construction of a highly influential ancient ship museum. The reporter learned that at present, Shanghai has determined the site of the yangpu riverside Shanghai shipyard site, using two old docks and preserved historical buildings to build the "Yangtze River Mouth No. 2" ancient ship museum.
In the future, archaeologists will gradually unveil the many unsolved mysteries of this ancient shipwreck of the Qing Dynasty here. At the same time, it will become a living museum, simultaneously carrying out archaeological excavations, cultural relics protection and display education, as well as archaeological and intangible cultural heritage living experience and international underwater cultural heritage scientific research. This will enhance the influence and discourse power of Chinese archaeology, especially underwater archaeology, in the international archaeological community.
"We will insist on leaving the best resources to the people, and build the Ancient Ship Museum into a cultural landmark of 'life show belt', so that more citizens and tourists can experience the charm of underwater archaeology, understand the profound nourishment of Chinese civilization, and feel the warm expression of the people's city." Fang Shizhong said.
Guangming Daily ( 2022-03-03 09 edition)
Source: Guangming Network - Guangming Daily