Fourteen skeletons of victims killed by an ancient earthquake excavated in 2000. Credit: Cai Linhai

Researchers have provided geological evidence for China’s “Great Flood,” a disastrous event on the Yellow River from which the Xia dynasty is thought to have been born.

Geological surveys in China have uncovered new evidence that may imply that China’s ancient history and beginnings need to be rereviewed and the period during which its most famous dynasty reigned might need to be adjusted.

According to oral and later written stories of the famous and mythical Xia Dynasty under its first emperor Yu – it began with a gigantic flood. The story of Yu was handed down for a millennium before entering the historical record, however.

A map of China depicting the Yellow River’s path (shown in blue in the upper half of the map) in the early 19th century.

The legend tells the story of how Yu saved China from flooding by digging and constructing channels. He did this with the help of a ‘channel-digging dragon’ and ‘magical, water-absorbing dirt’.

The Great Flood of Gun-Yu, also known as the Gun-Yu myth (traditional Chinese: 鯀禹治水), was a major flood event that continued for at least two generations, it plagued the Chinese heartland with frequent floods that prevented further economic and social development.

The legend tells us how Yu successfully devised a system of flood control. “According to the Shiji, Yu’s father labored unsuccessfully for 9 years to tame the flood before Yu took over for 13 more years. Yu’s success led to his mandate to become founding king of the Xia 22 years after the flood started.” Instead of directly damming the rivers’ flow, Yu made a system of irrigation canals which relieved floodwater into fields, as well as spending great effort dredging the riverbeds.

Some scholars have argued that the story is either a historicized version of an older myth or propaganda to justify the centralized power of imperial rule. But geologists are now finding that at least some parts of the story appear to be real.

If this enormous flood really happened has been disputed. An international team of researchers was mapping ancient sediments along the Yellow River when they stumbled across sedimentological records indicating that a powerful flood did indeed deluge the land thousands of years ago.

This was one of the largest floods to have happened on Earth in the last 10,000 years,” study co-author Darryl Granger, professor in the department of earth atmospheric planetary sciences at Purdue University, said in a press conference. The flood was likely to have destroyed settlements as far as 2,000 kilometers (1,240 miles) downstream.

“The … flood shares the main characteristics of the Great Flood described in ancient texts,”

– The study authors write.

If their flood is indeed the event that came to be known as the Great Flood, researchers could propose a new start date for the Xia dynasty. Using radiocarbon dating on a couple of skeletons, of a people killed by an earthquake and then buried by the flood, they determined that it occurred in the year 1920 BCE. This is between 200 and 300 years later than previously thought.

It appears as if a natural dam collapsed – initially caused by an earthquake and landslide. These hypothesized events began with an earthquake that caused a landslide and thus a dam, while a village downstream was destroyed and people died in the earthquake – they were then buried in sediments when the dam burst.

Taken together, these results reveal how the concurrence of these major natural and sociopolitical events may be an “illustration of a profound and complicated cultural response to an extreme natural disaster that connected many groups living along the Yellow River”.
Qinglong Wu et al. Outburst flood at 1920 BCE supports historicity of China’s Great Flood and the Xia dynasty. Science 4 augusti 2016. Doi: 10.1126/science.aah4040.