Wikimedi'Òc

Limestone-sandstone.jpg - Soerfm

Sioux Quartzite.jpg - Awickert

Jaspilite banded iron formation (Soudan Iron-Formation, Neoarchean, ~2.69 Ga; Stuntz Bay Road outcrop, Soudan Underground State Park, Soudan, Minnesota, USA) 41 (19199530646).jpg - Natuur12

Jaspilite banded iron formation (Soudan Iron-Formation, Neoarchean, ~2.69 Ga; Stuntz Bay Road outcrop, Soudan Underground State Park, Soudan, Minnesota, USA) 1 (19199008986).jpg - Natuur12

Wormstone (heavily bioturbated quartzose sandstone) (Mazomanie Formation, Upper Cambrian; riverside cliff, western side of the St. Croix River, northeast of Lookout Point, Minnesota, USA) 1 (18381933853).jpg - Natuur12

Wormstone (heavily bioturbated quartzose sandstone) (Mazomanie Formation, Upper Cambrian; riverside cliff, western side of the St. Croix River, northeast of Lookout Point, Minnesota, USA) 5 (18814890770).jpg - Natuur12

Geologic Map of Minnesota- Bedrock Geology (2011).pdf - Kablammo

"Rockville White Granite" (porphyritic granite, Rockville Granite, late Paleoproterozoic, 1.73 to 1.78 Ga; quarry near Rockville, Minnesota, USA) 1 (25902855894).jpg - Rudolphous

"Rockville White Granite" (porphyritic granite, Rockville Granite, late Paleoproterozoic, 1.73 to 1.78 Ga; quarry near Rockville, Minnesota, USA) 3 (25904916323).jpg - Rudolphous