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Obolon' crater Ukrainian: Оболонь is a 20 km (12 mi) diameter buried meteorite impact crater situated about 200 km (120 mi) southeast of Kyiv in Ukraine (Poltava Oblast).The site has been drilled, which revealed the presence of shocked minerals and impact melt rock; the high chlorine content of the latter suggesting that the area was covered by shallow sea at the time of impact.One estimate puts the age at 169 ± 7 million years (Middle Jurassic).