Scientists have found evidence of a catastrophic flood that overwhelmed the upper Yellow River valley in China some 4,000 years ago, an event that they say may confirm the historical basis of China’s semi-legendary first dynasty.
Ancient Chinese texts record a mix of historical events and legends. Some records, such as those relating to China’s second and third dynasties, were confirmed in surprising detail when archaeologists turned up inscriptions on oracle bones and ancient bronzes.
But records of the first dynasty, that of the Xia, contain stories of a Great Flood with a Noah-like savior, the Emperor Yu, who gained the mandate of heaven after dredging canals to dispel the floodwaters and make the land safe. Historians have long wondered whether this flood account was a creation-style myth, the folk memory of a real event, or some mixture of the two. Some have dismissed the story of Emperor Yu as a fiction intended to justify centralized rule and, in the absence of any evidence of a massive flood at the time, many have regarded the stories of the Xia dynasty as more myth than history.
A team of archaeologists and geologists led by Qinglong Wu of Peking University in Beijing has now discovered evidence of a massive flood that they say could be the Great Flood mentioned in the Chinese annals.
The setting for the flood was a landslide, caused by an earthquake, that planted a massive natural dam across the Yellow River where it travels through the Jishi Gorge after emerging from the Tibetan plateau. To judge from the remaining sidewalls, the researchers wrote in Friday’s issue of Science, the dam would have risen some 800 feet above the river’s present level.
For six to nine months, Dr. Wu’s team estimates, the river ceased to flow as water accumulated in the new lake behind the dam. Then, as the water overtopped the dam’s crest, the dam rapidly gave way, releasing up to 3.8 cubic miles of water, one of the largest known floods in the last 10,000 years. The outburst flood wave could have traveled as far as 1,250 miles downstream, breaking the river’s natural banks, causing extensive flooding and even making the Yellow River switch course.
Floods are often hard to date. But the same earthquake that dammed the river provided a date by destroying a village called Lajia some 16 miles downstream. Fissures caused by the earthquake are completely filled with sediment from the outburst flood, with no annual deposit of the windblown earth that is common in the region, which means the flood occurred the same year as the earthquake, Dr. Wu’s team says.
Radiocarbon dating of the bones of three children killed by the earthquake establish that the event took place around 1920 B.C.
The date offers a striking temporal link to the Xia dynasty which, if it existed, is thought to have begun at this time. A modern Chinese chronology project sets the beginning of the dynasty at 2070 B.C. Even closer, two scholars working from Chinese astronomical records — a statement that there was a close conjunction of five planets early in the reign of the Emperor Yu — have calculated that the dynasty began in 1914 B.C.
Chinese annals record that Emperor Yu contrived a recovery from the Great Flood by dredging drainage canals rather than trying to repair breaches in the Yellow River’s dikes, as his predecessor had done. He also laid the foundations for the Chinese civilization that followed by specifying which regions should send tribute. The place where he began his operations is recorded as Jishi, which has the same Chinese characters as that of the gorge where the landslide dam occurred.
Dr. Wu’s team said its reconstruction of the outburst flood from the Jishi Gorge showed that the ancient textual accounts of the Great Flood “may well be rooted in a historic natural event.” The finding also supports the idea, the researchers say, that archaeological remains found at Erlitou, a site about 1,550 miles downstream from the gorge, may have been the Xia capital, given that the Erlitou culture dates to 1900 B.C., the same time as the Jishi Gorge flood.
But historians may require more evidence before signing on to the team’s thesis. It is not so clear how a folk memory of the flood could have been accurately maintained for at least 900 years, as Dr. Wu’s team suggested, given that elements in the texts may begin as early as 1,000 years ago. There were probably many floods, which may have been conflated in popular memory, said Sarah Allan, a historian of ancient China at Dartmouth College. In her view, the Great Flood described in the ancient texts is a myth to explain how the world was made, not a historical event.
“The story begins with water everywhere and the problem is how to make the world habitable,” she said. Even if the myth was centered on a real event, it is a reach to associate this with the Jishi Gorge flood or the flood with the Erlitou culture, she said.
Paul Goldin, who studies China’s Warring States period at the University of Pennsylvania, also sees the stories of Yu and the Great Flood as unlikely to represent historical events. And they date mostly to the fourth century B.C., long after the Jishi Gorge flood. “These are relatively late legends that were propagated for philosophical and political reasons, and it’s inherently questionable to suppose that they represent some dim memory of the past,” he said.
Dr. Goldin remarked on a “kind of fixation” in Chinese archaeology “to prove all the ancient texts and legends have some fundamental truth, which is an overreaction to an earlier period when they were rejected as myth. It shouldn’t be every archaeologist’s first instinct to see if their findings are matched in the historical sources,” he said.
The Jishi Gorge flood occurred at a pivotal time in Chinese history, the boundary between the Neolithic Age and the Bronze Age that followed. Dr. Wu’s team said at a news conference on Wednesday that the story of Yu taming the flood represents the emergence of a new political order. The archaeological record shows some sort of a decline, as would be expected after a great catastrophe, followed in the Bronze Age, first seen in the Erlitou culture, by new levels of development, a large increase in the size of cities, the development of writing and workshops manufacturing bronze.
“If they can show some kind of connection in the archaeological record between the Jishi Gorge flood and the emergence of a culture like Erlitou, that would be a major improvement of our understanding of history,” Dr. Goldin said.
Nicholas Wade/The New York Times