Lake Yanisyarvi

Impact craters

The Janisjarwi (Russian Янисъярви; Finnish term Jänisjärvi ) is located north of Lake Ladoga in Russia, a 200 km ² large lake in the Republic of Karelia.

The lake is drained by the Jänisjoki and drained to the south Lake Ladoga. The catchment area of the lake covers 3660 km ².

The basin of the approximately circular lake is the result of a meteor impact before 700 ± 5 million years ago (according to other sources 698 ± 22 million years) during the Cryogeniums.

The impact crater has a diameter of 14 km.

Before the Second World War, still assumed that this was the second known volcanic caldera in Finland - the other was the lake Lappajärvi. Later it turned out that both lakes have formed in impact craters.