Wikimedi'Òc

Ophitic basalt (Scales Creek Flow, Portage Lake Volcanic Series, upper Mesoproterozoic, ~1.095-1.096 Ga; Seventh Street roadcut, Houghton, Upper Peninsula of Michigan, USA) (8282036164).jpg - Ser Amantio di Nicolao

Glacially-grooved basalt (Scales Creek Flow, Portage Lake Volcanic Series, upper Mesoproterozoic, ~1.095-1.096 Ga; Surveyor's Arch outcrop, Houghton, Upper Peninsula of Michigan, USA) (8280979561).jpg - Ser Amantio di Nicolao