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.
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. Some minor kukersite resources occur in sedimentary basins of Michigan, Illinois, Wisconsin, North Dakota, and Oklahoma in North America and in the Amadeus and Canning basins of Australia.
==Baltic Oil Shale Basin== thumb|250px|Location of the kukersite deposits within the Baltic Oil Shale Basin in northern Estonia and Russia The Baltic Oil Shale Basin covers about . Main kukersite deposits are Estonian and Tapa deposits in Estonia, and Leningrad deposit in Russia (also known as Gdov or Oudova deposit). Other occurrences in Russia are Veimarn and Chudovo–Babinskoe deposits. The Estonian deposit, which covers about , is exploited industrially; the Tapa deposit is not accounted as reserves due its lower value which makes its extraction economically inexpedient. The Leningrad deposit was exploited industrially but operations have ceased.
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