An ancient Chinese legend tells the story of a hero who saved China from a devastating Great Flood of the Yellow River that left people homeless and destroyed farmlands.
With the help of a dragon and a magical water-absorbing dirt, Yu the Great dredged the river bed and controlled the floodwaters saving the people. He eventually went on to establish the Xia Dynasty, the first in China's traditional history.
The elements of the story indicate that it is a myth but researchers have now found evidence that China's legendary "Great Flood" really happened. A catastrophic flood that occurred around 1920 B.C. could be the basis of this legend.
In a new study published in the journal Science on Aug. 4, geologist Qinglong Wu, from Peking University in Beijing, and colleagues reconstructed ancient events along the Yellow River that led to the disastrous flood following a discovery of ancient lakebed sediments in the Jishi Gorge, an upstream river valley for the Yellow River, which hinted that at some point in time, the river may have been blocked.
Based on evidence gathered from sedimentary deposits, ancient texts, skeletons in collapsed caves and earthquake-triggered landslides, Wu and colleagues described an event in which an ancient landslide created a dam 200 meters high that blocked the Yellow River, the third longest river in Asia, for six to nine months.
When the dam burst, waters flooded the lowlands downstream. Scientists calculated that these waters rushed forward at a rate of up to 500,000 cubic meters per second resulting in damage that could have likely extended as far as 2,000 kilometers (1,243 miles) downstream.
"That's roughly equivalent to the largest flood ever measured on the Amazon River, the world's largest river," said geologist Darryl Granger, from Purdue University. "It's among the largest known floods to have happened on Earth during the past 10,000 years."
By using radiocarbon dating on human bones, the researchers estimated that the flood happened in 1920 B.C., which suggests that the Xia dynasty started much later than previously thought. The Xia dynasty is originally believed to have started in 2070 B.C. but there was insufficient evidence to support this.
"This would place the beginning of Xia at ~1900 BCE, several centuries later than traditionally thought," the researchers wrote in their study.
"This date coincides with the major transition from the Neolithic to Bronze Age in the Yellow River valley and supports hypotheses that the primary state-level society of the Erlitou culture is an archaeological manifestation of the Xia dynasty."