Ilyinets
Key facts
- Country
- Ukraine
- Diameter
- 8.5 km
- Age
- about 378 ± 5 million years
- Location
- 49.12° N, 29.10° E
A low, partly eroded structure in farmland near the town of Illintsi in Vinnytsia Oblast, central Ukraine. Impact rocks are exposed in a few outcrops and quarries.
Ilyinets is an impact structure about 8.5 km across near the town of Illintsi (Ilyinets) in Vinnytsia Oblast, central Ukraine.
What it hit. The impactor struck the Ukrainian Shield, a region of ancient crystalline rocks, granites and gneisses about 2 billion years old. The impact melted and shattered the target, forming breccias and impact melt rock.
Proof of impact. In the 1970s geologists recognised that unusual rocks in the area were impact breccias and melt rocks. Quartz and feldspar in these rocks show shock features, including planar deformation features. The structure has been drilled.
Age. Argon dating of the impact rocks gives an age of about 378 million years, in the Late Devonian, with an uncertainty of about 5 million years.
Why it matters. Ilyinets is one of more than half a dozen impact structures on the Ukrainian Shield, which, like the Canadian and Baltic shields, is an old, stable region where craters survive well. The impactor is unknown.
Visiting. Impact rocks can be seen in some outcrops and quarries. Ask permission before entering, and take care near quarry faces.
Did you know?
Rock melted by the impact survives at Ilyinets.
It is one of several impact structures on the Ukrainian Shield.
It formed in the Late Devonian, about 378 million years ago.