A team of geologists have discovered a crater named “Yilan Crater”, in northwest of Yilan in Heilongjiang Province of China.
Highlights
- Prior to 2020, only one impact crater “Xiuyan Crater” was discovered in Liaoning province, despite China’s large land area.
- Then, in 2021, Yilan crater was discovered in heavily forested Lesser Xing’an mountain range. The local residents knew it as “Quanshan,” or “circular mountain ridge.”
Characteristics of Yilan crater
Yilan crater is slightly larger than Xiuyan. It spans about 1.85 kilometers. Thus, it is the largest crater on Earth under 100,000 years old. Carbon-14 dating sediments suggests that, this crater was formed between 46,000 and 53,000 years ago.
Meteor or Barringer Crater
Meteor or Barringer crater in Arizona is also around 50,000 years old. However, its diameter is 1.2 kilometers.
Findings by researchers
- To investigate the impact structure, the team drilled down 438 meters at the center of the crater. They found hundreds of meters of ancient lake sediments and shattered granite.
- They also found unambiguous evidence that the structure was indeed an impact crater.
- The core revealed shocked quartz, glass containing holes formed by gas bubbles, melted granite, and tear-drop shaped glass fragments. These factors indicate a high-intensity impact event.
- Presence of lakebed sediments inside this crater highlights that, rim was intact long enough for significant deposits for building up on the lake bottom. Such deposits produce rich organic soil.
Yilan crater
Yilan crater is an impact crater in China. It is situated to the northwest of Yilan town in Heilongjiang province. Its southern rim has eroded. However, northern rim is visible on the surface as crescent-shaped ridge.