Aerial view of the structure site
With a diameter of between 820 and 900 meters and a depth of 90 meters, it is much larger than Russia’s Macha crater at 300 meters, previously the largest known Holocene impact structure.
Nestled on a hillside in Guangdong province, near the city of Zhaoqing, the cratera Jinlin managed to hide in plain sight until, last month, in a study at Matter and Radiaton at Extremesresearchers identified her as a impact crater.
There are only about 200 of these types of confirmed structures worldwide, making each discovery scientifically valuable. But this one, in particular, stands out for its exceptional size and youth.
According to the study, the crater was formed during the Holocene period, when the last ice age ended. about 11,700 years ago.
Based on measurements of soil erosion nearby, researchers estimate that it was excavated somewhere between the early and mid-Holocene.
Common diameter between 820 and 900 meters and a depth of 90 metersis much larger than Russia’s Macha crater, at 300 meters, previously the largest known Holocene impact structure.
As , finding such a massive and well-preserved crater is surprising, given the region’s climate.
Guangdong province experiences heavy rain and high humidity — precisely the conditions that accelerate erosion and which should have long since obliterated any visible crater.
Not so much, Jinlin crater remains remarkably intactpreserved within thick layers of weathered granite that protected its structure from the elements.
The proof that confirms its extraterrestrial origin is in the details. Inside the granite, researchers found numerous quartz fragments that display planar deformation characteristics — microscopic features that serve as geological fingerprints of impact events.
“On Earth, the formation of planar deformation features in quartz occurs only through intense shock waves generated by impacts from celestial bodies,” he explained to Universe Today, Ming Chenleader of the study of Centre for High Pressure Science and Technology Advanced Researchin Shanghai.
No volcanic eruption, earthquake or tectonic movement creates such intense and focused shock waves. Only the hyperfast collision of an extraterrestrial object produces these revealing signatures.
Investigators determined that the impactor was a meteorite and not a comet, since a comet would have excavated a crater at least 10 kilometers wide.
