A New Chapter in Deep-sea Archaeology

Today, we’ll talk about the discovery and exploration of two 500-year-old shipwrecks in the South China Sea as well as some of the history of China’s underwater archaeology and its recent technological advancements.

On May 21, a stunning archaeological discovery was made public in Sanya, a popular tourist destination in southern China’s Hainan Province. Not one, but two Ming Dynasty shipwrecks were found on the northwest continental slope of the South China Sea at a depth of about 1,500 meters.

Director of the archaeology department of the National Cultural Heritage Administration, Yan Yalin, said at the news conference that “the wrecks are both relatively well-preserved and a large number of relics have been uncovered.”

He added that “the well-preserved relics are of high historical, scientific and artistic value. It may constitute a world-class deep-sea archaeological discovery.”

The two wrecks are named by researchers as Northwest Continental Slope No 1 and No 2 Shipwrecks in the South China Sea, and they are expected to provide important clues about the trade routes of the Maritime Silk Road.

At present, China has begun to investigate and map the two five-century-old shipwrecks, and while their exact locations have not been released, images from the initial searches have been made public, and a metal surveying marker has been placed on the seabed of shipwreck No 1 to facilitate further research.

Preliminary investigations showed that relics from the No 1 shipwreck were scattered across about a 10,000-square-meter area. It is estimated that over 100,000 cultural relics, mainly porcelains, are sealed on the spot. As for the No 2 shipwreck, numerous processed wooden logs are neatly arranged together with a small number of ceramics.

Now, you may be interested in hearing how were these two shipwrecks were discovered.

It was just last fall, in October of 2022, that the Institute of Deep-sea Science and Engineering under the Chinese Academy of Sciences was on a research mission, and when it reached a depth of about 1,500 meters on the northwest continental slope of the South China Sea, there suddenly appeared a 3-meter-high “hill” made of densely packed porcelain. Not far away, the team also spotted another wreck, which featured a large number of logs.

The research team immediately reported the news to the national and local cultural heritage departments. After studies by archaeologists, it was determined that the first wreck was from the reign of Zhengde Emperor of the Ming Dynasty, who ruled from 1506 to 1521, and the No 2 wreck was from the reign of Hongzhi Emperor, lasting from 1488 to 1505.

Underwater archaeologists will spend about a year to investigate the two shipwrecks in three phases. The first phase lasted from May 20 to June 10, using a manned submersible to search and map out the distribution of the wrecks, conduct data collection and recording work on the site, and extract specimens and testing samples. The second phase will be implemented from August to September of this year and the third phase is planned for March through April of 2024. After the investigation is completed, the preservation status and technical conditions of the wrecks will be assessed so the next phases of archaeology and site protection can be implemented.

Deep-sea archaeology cannot realize the overall salvage of these wrecks, so in order to bring historians as well as the general public closer to the deep-sea relics, the team will carry 4K and 8K camera equipment to the ocean floor to shoot the underwater relic sites. Meanwhile, the team will use dynamic 3D laser scanning technologies to generate a distribution map of relics in the core area of the No 1 wreck, and provide basic data for the future application of virtual reality technology to digitize them.

China has an ancient civilization and a large number of its precious cultural relics have been buried at sea, and particularly the South China Sea is richly imbued with artifacts from its maritime history.

In 1984, British explorer and shipwreck salvage expert Michael Hatcher found an East India Company merchant ship, the Geldermalsen, in the South China Sea. It had been sunk for more than 200 years and was full of porcelain and gold. More than one million pieces of cultural relics such as blue and white porcelain were salvaged. However, in order to maximize profits, he only inventoried 239,000 pieces of blue and white porcelain, 125 gold ingots, and two bronze cannons engraved with the initials of the Dutch East India Company; meanwhile, the remaining pieces of blue and white porcelain and other cultural relics that were considered to have little circulation value were destroyed.

In 1986, Hatcher obtained the auction permit under the pretext that the Geldermalsen was unclaimed by any nation. He commissioned the Dutch auction house Christie’s to conduct an auction of the artifacts. The Chinese embassy in the Netherlands then sent the news home, but when the National Cultural Heritage Administration wanted to stop the auction, it looked through the UN Convention on the Law of the Sea, but couldn’t find any valid legal basis to force the return of the relics to China.

Buying them back was the only feasible way. The Heritage Administration dispatched two experts, Feng Xianming and Geng Baochang, to Amsterdam with US$30,000 in their pockets. But the starting price of the relics was far beyond their imagination, and the duo could not even afford to enter a single bid during the entire three-day auction. In the end, every one of the nearly 240,000 pieces of treasure were sold to overseas bidders.

This incident was a wake-up call to Chinese archaeologists. So, in March 1987, the National Cultural Heritage Administration took the lead in establishing the National Coordination Group for Underwater Archaeology, and thus underwater archaeology in China was officially launched. Since then, the Administration has sent staff to countries including Japan, the Netherlands, and Australia to study diving and other cutting-edge techniques, and initially built up a team of more than 10 experts in underwater archaeology.

Also in 1987, when the British searched the archives of the East India Company, they found that a ship named Rheinberg sank in the Taishan and Yangjiang waters of Guangdong Province. It carried six chests of silver and more than 300 tons of tin ingots.

In August of that year, China Rescue & Salvage decided to cooperate with a British maritime expedition and salvage company to excavate this shipwreck, and the Guangzhou Salvage Bureau, a subsidiary of China Rescue & Salvage, took the job.

During the joint search for the Rheinberg shipwreck, they accidentally discovered an ancient wooden wreck from the early Southern Song Dynasty. Later named Nanhai No 1, it had been transporting mostly porcelain when it sank 24 meters below the surface. This was the first shipwreck site found in China representing the Maritime Silk Road. And since its discovery, over 60,000 precious cultural relics have been recovered.

Nanhai No 1 was sailing from Quanzhou Port when it sank in the waters of Yangjiang City of Guangdong Province. And although this wooden shipwreck had been sleeping on the seabed for more than 800 years, it was covered by a blanket of silt, which greatly slowed the decomposition of its hull and cargo by seawater and microorganisms. In the 13 compartments, archaeologists have unearthed hundreds of tons of goods, including a large number of porcelains, coins, gold and silver, lacquerware, metal products, and other popular export commodities, many of which are valuable treasures. 

Nanhai No 1 is the earliest, largest and best-preserved ocean-going merchant ship among the maritime shipwrecks found in the world so far, and more than 200,000 pieces of cultural relics have been salvaged, which is very important for studying the ancient history of shipbuilding, ceramics, and trade in Southeast Asia.

The porcelain on the shipwreck is from the Song and Yuan dynasties, lasting from the 10th century to 14th century. In the collecting world, even fragments of porcelain during this period are great treasures that collectors compete for. In the eyes of the archaeologists, however, protecting the hull of this Southern Song wreck is more important than excavating the artifacts.

According to international practices at that time, the salvage work would often focus on the shipborne artifacts first, then take the ship apart, fish them up for protection and then reassemble it. If that had been the case, the whole ship structure would have been damaged. So, the archaeological team, after many arguments, innovatively proposed a whole salvage plan. Simply put, they created a huge tin box, sank it to the salvage area, encased the hull, added steel beams across the bottom, and used the crane to lift it up as a single unit. In the history of underwater archaeology around the world, this approach had never been attempted, but it worked!

In December 2007, Nanhai No 1 was pulled out of the water and moved into the Maritime Silk Road Museum of Guangdong, which was built just for it. This huge “crystal palace” also became the archaeological excavation site, and visitors can see the relics while watching how they were excavated. This approach to conservation, salvage, and display is the first of its kind in the world.

The successful recovery of Nanhai No 1 has greatly encouraged Chinese underwater archaeologists. And in the ocean depths, there are many shipwreck sites waiting to be brought to the surface.

In 2011, the Shanghai Municipal Bureau of Cultural Heritage launched a census of underwater cultural heritages, first exploring the waters of the Yangtze estuary, where visibility is almost nil.

In 2015, a relatively well-preserved iron shipwreck was discovered in the waters of Chongming Hengsha water zone in Shanghai, and it was assigned the archaeological number Changjiangkou No 1. Subsequently, another large and well-preserved wooden wreck was found to the north of the iron wreck and given the archaeological number Changjiangkou No 2. From then on, the prelude of decoding the wreck of Changjiangkou No 2 began.

After several years of underwater exploration, the basic situation of Changjiangkou No 2 was discovered. The wreck is a wooden sailing ship, confirmed to be in the reign of Tongzhi period of the Qing Dynasty, who ruled from 1862 to 1875. The ship is a flat-bottomed vessel widely used for water transportation in Shanghai during the Ming and Qing dynasties.

The wreck is located at a water depth of 8 to 10 meters, and the hull is buried in 5.5 meters of deep silt. It’s 38.1 meters long, 9.9 meters wide, and 31 compartments have been identified. To this day, a large number of fine cultural relics such as Jingdezhen kiln porcelain have been found, along with purple sand wares, water pipe jars from Vietnam, and remnants of wooden water buckets.

After the Nanhai No 1 wreck, the Changjiangkou No 2 wreck marks another milestone in Chinese underwater archaeology as it is one of the largest, most complete and well-preserved ancient wooden shipwrecks both in China and abroad, with a huge number of artifacts found on board.

However, the archaeological work of the wreck of Changjiangkou No 2 still belongs in the category of shallow water operation.

Due to the limitations of deep diving technology, Chinese underwater archaeology used to be active in waters only within 50 meters of depth, with scuba diving as the main mode of operation. For example, in the early archaeological investigation of Nanhai No 1, archaeologists could dive to more than 20 meters underwater several times, touch the hull with their own hands, and take clear images of Nanhai No 1. But when the water depth exceeds 50 meters or even 100 meters, the difficulty of scuba diving operations  soars, and efficiency plummets.

In the vast South China Sea along the ancient Maritime Silk Road, a large number of ancient merchant ships are known to have sunk, but how to enter the deep sea to obtain information about these shipwrecks has become an urgent task for China’s underwater archaeology. Where Chinese underwater archaeologists were once helpless in the face of the South China Sea’s average depth of 1,200 meters and an area of more than 2 million square kilometers, the solution has been found in continuous technological innovations.

From 2009 to 2012, China’s first manned deep submersible Jiaolong achieved successful deep dives one after another. Shortly afterwards, the aptly named submersible Shenhai Yongshi, or Deep-sea Warrior, has significantly slashed deep-water diving costs. In 2020, the Fendouzhe, or Striver, successfully sat at the bottom of the Mariana Trench at a depth of 10,000 meters, which not only set a new record for manned deep diving in China, but also marked the formation of China’s all-sea deep diving capabilities.

The discovery of the wrecks of Northwest Continental Slope No 1 and No 2 Shipwrecks is a perfect example of applying cutting-edge deep-sea technologies in the field of underwater archaeology. For example, to ensure their safety, soft robotics, which are based on biomechanics and material science, were adopted to salvage the fragile relics. Other new technical approaches were used for scanning, photography, and supervision surrounding the shipwrecks.

Cui Yong, former team leader of the Nanhai No 1 protection and excavation project, said during an interview with Science and Technology Daily that a shipwreck site is like a time capsule in that it preserves nearly intact a certain sliver of time in some bygone era. It reflects not only the ship’s cargo, but also temporal and spatial information serving as a window into the political and social ecology of the time.

He added that “compared to a particular individual ritual or burial site that is the object of field archaeology, a shipwreck can bring more diverse and comprehensive historical information.”

Deep-sea archaeology has greatly expanded the scope of underwater archaeology, extending its reach to previously inaccessible areas and enabling the precious heritage that used to lie dormant at the depths of the ocean to be presented to us directly and in three dimensions.

Well, that’s the end of our podcast. Our theme music is by the famous film score composer Roc Chen. We want to thank our writer Lü Weitao, translator Du Guodong, and copy editor Pu Ren. And thank you for listening. We hope you enjoyed it, and if you did, please tell a friend so they, too, can understand The Context.