Chadron Formation
Chadron Formation is a rock formation in North Dakota, South Dakota and Nebraska. It is named after the town of Chadron, Nebraska. It was mapped out by Carl Vondra in the 1950s.
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Wikipedia
Chadron Formation is a rock formation in North Dakota, South Dakota and Nebraska. It is named after the town of Chadron, Nebraska. It was mapped out by Carl Vondra in the 1950s.