Here, scientists from China and the U.S. describe the discovery of a major impact structure termed Jinlin Crater in Zhaoqing, Guangdong Province, China. This fab 34 crater is a whopping 900m across! It’s the biggest crater of the Holocene epoch—defined as starting about 11,700 years ago at the end of the last ice age.
The Jinlin Crater located on a picturesque hillside, was formed by a meteorite impact. This is what sets it apart from craters made by comets that are typically more than 10 kilometers across. For a young crater in geological terms, the crater is actually in fine shape. This preservation is particularly remarkable given the severe climate of this desert southern region. It gets pounded by rain and humidity from the monsoon season.
The Jinlin Crater is one of only a little over 200 known today craters around the world. This special designation emphasizes its global significance for the study of extraterrestrial impacts on our planet. This finding is likely to provide more insight into the distribution, geological evolution, and impact history of small celestial bodies.
Ming Chen of UCR, the study’s lead author and research scientist, noted that this finding has huge implications. He noted that extreme shockwaves from astrological impacts produce planar deformation features in quartz found within the crater. This constellation of factors amplifies the damaging forces at work during these events.
“On Earth, the formation of planar deformation features in quartz is only from the intense shockwaves generated by celestial body impacts, and its formation pressure ranges from 10 to 35 gigapascals, which is a shock effect that cannot be produced by any geological process of Earth itself.” – Ming Chen
In particular, Chen emphasized the wider significance of the Jinlin Crater. The purpose of the Geologic Time Scale Act, he noted, is to be a living record of Earth’s impact history.
“The impact crater is a true record of Earth’s impact history.” – Ming Chen
He pointed out that this result means we have recently greatly underestimated the scale of impacts from small extraterrestrial objects during the Holocene.
“This discovery shows that the scale of impacts of small extraterrestrial objects on Earth in the Holocene is far greater than previously recorded.” – Ming Chen