- Riachão Ring
Riachão Ring is a
meteorite crater (astrobleme) inBrazil .It is 4.5 km in diameter and the age is estimated to be less than 200 million years (
Jurassic or younger). The crater is exposed at the surface. [cite web | title=Riachao Ring | work=Earth Impact Database | url=http://www.unb.ca/passc/ImpactDatabase/images/riachao-ring.htm | accessdate=2007-10-22 ]References
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