A recently uncovered impact crater in China’s Heilongjiang province is likely the youngest major impact structure on Earth, according to researchers. The nearly circular depression, spanning approximately 1.15 miles (1.85 km) across, was first identified in satellite imagery in , though locals had long known of the unusual geological formation, referring to it as “Quanshan,” or “circular mountain ridge.”
The Yilan crater, located in the Lesser Xing’an mountain range, is approximately 12.5 miles (20 kilometers) northwest of the town of Yilan. Its ringed walls rise up to 500 feet (150 meters) above the crater floor, though the southern third of the rim appears to be missing.
Carbon-14 dating of charcoal and organic lake sediments suggests the crater formed between and years ago. This places it in the same age range as the Meteor Crater (also known as Barringer Crater) in Arizona, which formed around years ago. Researchers are currently investigating whether the Yilan crater is definitively younger.
The discovery is significant because relatively few impact craters have been identified in China, despite its large land area. Prior to , only the Xiuyan crater in Liaoning province had been confirmed. The Xiuyan crater, approximately 1.1 miles (1.8 km) in diameter, is considerably older, dating back between 330,000 and 1.1 million years.
What initially drew researchers to the Yilan structure was evidence of “shocked quartz, melted granite, glass containing holes formed by gas bubbles, and tear-drop-shaped glass fragments” found during drilling operations that reached a depth of 1,440 feet (440 meters). These features are telltale signs of a high-velocity impact event.
The identification of the Yilan crater as an impact structure adds to our understanding of Earth’s geological history and the ongoing threat posed by near-Earth objects. While large impacts are rare, they can have significant consequences for the planet and its inhabitants. The Yilan crater is now considered the largest impact crater on Earth under 100,000 years old.
The discovery wasn’t immediate. While the geological feature was known to local residents, its extraterrestrial origin wasn’t recognized until a team of Chinese geologists investigated in mid-. The crater’s location within a heavily forested area likely contributed to it remaining unnoticed for so long.
Further research has continued to uncover additional impact structures in China. In , scientists announced the discovery of a third crater, also approximately 1.85 kilometers in diameter, carved into a mountaintop near the North Korean border. More recently, in , the Jinlin crater was confirmed near Zhaoqing in Guangdong province, though it is significantly smaller, measuring around 900 meters (3,000 feet) in diameter. The age of the Jinlin crater remains unconfirmed, but it may be relatively recent, potentially dating to the current geological epoch, the Holocene, which began approximately 11,700 years ago.
The increasing number of impact crater discoveries in China suggests that the region may have experienced a higher frequency of impact events than previously thought, or that improved detection methods are simply revealing previously unknown structures. Continued research and monitoring will be crucial to further understanding the impact history of our planet.
