> "If found to be true, the wannabe petroglyph could be as much as 10,000 years old – coincident with the post-Ice Age presence of both humans and mastodons in

> "If found to be true, the wannabe petroglyph could be as much as 10,000 years old – coincident with the post-Ice Age presence of both humans and mastodons in the upper midwest. The formation, if authenticated, wouldn’t be completely out of place. Stone circles and other petroglyph sites are located in the area." But if it's under 40 ft of water wouldn't that mean it was constructed (?) during the Ice Age? Not after?