Geology of Estonia

thumb|Outcrop of Ordovician kukersite oil shale, northern Estonia Kukersite is a light-brown marine type oil shale of Ordovician age. It is found in the Baltic Oil Shale Basin in Estonia and North-West Russia. It is of the lowest Upper Ordovician formation, formed some 460 million years ago. It was named after the German name of the Kukruse Manor in the north-east of Estonia by the Russian paleobotanist Mikhail Zalessky in 1917.

natural phenomenon