Xiuyan
Key facts
- Country
- China
- Diameter
- 1.8 km
- Age
- about 50,000 years
- Location
- 40.35° N, 123.45° E
A round, wooded bowl about 1.8 km across and about 150 m deep in the hills of Xiuyan County, Liaoning Province, north-eastern China. Its floor is farmland.
Xiuyan is a simple bowl-shaped impact crater about 1.8 km across in Liaoning Province, north-eastern China. In 2009 it became the first impact crater confirmed in China.
What can be seen. The crater is a round bowl in the hills, with a rim about 150 m above its floor. The floor is flat because the bowl has been partly filled by lake and stream sediments, and it is now used for farming.
What it hit. The impactor struck ancient metamorphic rocks, mainly marble, gneiss and schist about 2 billion years old.
Proof of impact. Chinese scientists drilled into the crater floor and recovered a core more than 300 m long. Beneath the sediments lay a thick layer of breccia, broken and partly melted rock that fell back into the crater. In it they found quartz with planar deformation features and coesite, a dense form of silica that forms only at very high pressures. These proved an impact.
Age. The age is not precisely known. The sediments filling the crater suggest it is about 50,000 years old, in the late Pleistocene.
Why it matters. Xiuyan showed that impact craters could be found in China, a country with few known examples at the time, and encouraged searches that have since found Yilan and Jinlin. The impactor is unknown.
Visiting. The crater is in farmland and forest. Ask permission before entering private land.
Did you know?
Xiuyan was the first impact crater confirmed in China, in 2009.
A drill core more than 300 m long was recovered from the crater floor.
The crater floor is now farmland.