Today’s Image of the Day from NASA Earth Observatory features an impact crater that was recently uncovered northwest of Yilan in Heilongjiang Province.
“The crater was discovered in the heavily forested Lesser Xing’an mountain range, where local residents knew it as ‘Quanshan,’ or ‘circular mountain ridge,'” reports NASA.
Prior to 2020, the Xiuyan crater in Liaoning province was the only impact crater that had been found in China.
The Yilan crater is slightly larger than Xiuyan. With a length of 1.15 miles, it is the largest crater on Earth under 100,000 years old.
The northern rim rises about 500 feet above the crater floor. While the northern rim is visible in the image, the southern rim is not.
“The researchers continue to investigate the cause of the missing southern rim. However, the presence of lakebed sediments inside the crater suggests the rim was intact long enough for significant deposits to build up on the lake bottom,” explains NASA.
“Such deposits often produce rich, organic soil; some farm fields can be seen inside the southern part of the crater. The rest of the crater interior is covered with swamps and forest wetlands.”
According to NASA, even though the asteroid that created the crater hit the Earth relatively recently in geologic time, the granite rocks it impacted were much older. These rocks had formed about 200 million years ago in the Early Jurassic Period.
The image was captured on October 8, 2021 by the Operational Land Imager (OLI) on Landsat 8.
Image Credit: NASA Earth Observatory