Mizarai
Key facts
- Country
- Lithuania
- Diameter
- 5 km
- Age
- about 500 ± 20 million years
- Location
- 54.02° N, 23.90° E
Nothing: the crater is buried beneath forest and farmland in southern Lithuania, near the border with Poland and Belarus.
Mizarai is a buried impact crater about 5 km across in Alytus district, southern Lithuania, close to the borders with Poland and Belarus.
Discovery. The structure first appeared as a round gravity and magnetic anomaly in geophysical surveys. Drilling found broken crystalline rock and breccia beneath younger sediments. Quartz grains in the breccia contain planar deformation features, the microscopic signature of shock, confirming an impact.
What it hit. The impactor struck crystalline basement rocks, ancient granites and gneisses about 1.8 billion years old, probably covered by a thin layer of early Palaeozoic sediment, possibly on the floor of a shallow sea.
Age. The age, about 500 million years with an uncertainty of about 20 million years, comes from the sediments that filled the crater soon after it formed, which are of Cambrian to Ordovician age.
Why it matters. Mizarai is one of Lithuania's two known impact structures, with Vepriai. Both are hidden beneath the plains and were found only because the country's ancient basement has been explored with many boreholes. The impactor is unknown.
Did you know?
Mizarai was first noticed as a gravity and magnetic anomaly.
It lies close to the borders with Poland and Belarus.
The crater filled with sea-floor sediments about 500 million years ago.