Palisade Rhyolite (Mesoproterozoic, 1096-1097 Ma; Lake Superior area, USA) by James St. John ● portfotolio

James St. John: Columnar-jointed rhyolite (Palisade Rhyolite, North Shore Volcanic Group, Mesoproterozoic, 1096-1097 Ma; Palisade Head, northeastern Minnesota, USA) 1

James St. John: Columnar-jointed rhyolite (Palisade Rhyolite, North Shore Volcanic Group, Mesoproterozoic, 1096-1097 Ma; Palisade Head, northeastern Minnesota, USA) 2

James St. John: Columnar-jointed rhyolite (Palisade Rhyolite, North Shore Volcanic Group, Mesoproterozoic, 1096-1097 Ma; Palisade Head, northeastern Minnesota, USA) 3

James St. John: Rhyolite (Palisade Rhyolite, North Shore Volcanic Group, Mesoproterozoic, 1096-1097 Ma; Rt. 1 roadcut just north of Ilgen City, Minnesota, USA) 1

James St. John: Rhyolite (Palisade Rhyolite, North Shore Volcanic Group, Mesoproterozoic, 1096-1097 Ma; Rt. 1 roadcut just north of Ilgen City, Minnesota, USA) 2

James St. John: Rhyolite (Palisade Rhyolite, North Shore Volcanic Group, Mesoproterozoic, 1096-1097 Ma; Rt. 1 roadcut just north of Ilgen City, Minnesota, USA) 3

James St. John: Rhyolite (Palisade Rhyolite, North Shore Volcanic Group, Mesoproterozoic, 1096-1097 Ma; Rt. 1 roadcut just north of Ilgen City, Minnesota, USA) 4

James St. John: Rhyolite (Palisade Rhyolite, North Shore Volcanic Group, Mesoproterozoic, 1096-1097 Ma; Rt. 1 roadcut just north of Ilgen City, Minnesota, USA) 5

James St. John: Rhyolite (Palisade Rhyolite, North Shore Volcanic Group, Mesoproterozoic, 1096-1097 Ma; Rt. 1 roadcut just north of Ilgen City, Minnesota, USA) 6

James St. John: Rhyolite (Palisade Rhyolite, North Shore Volcanic Group, Mesoproterozoic, 1096-1097 Ma; Rt. 1 roadcut just north of Ilgen City, Minnesota, USA) 7

James St. John: Rhyolite (Palisade Rhyolite, North Shore Volcanic Group, Mesoproterozoic, 1096-1097 Ma; Rt. 1 roadcut just north of Ilgen City, Minnesota, USA) 8

James St. John: Rhyolite (Palisade Rhyolite, North Shore Volcanic Group, Mesoproterozoic, 1096-1097 Ma; Rt. 1 roadcut just north of Ilgen City, Minnesota, USA) 9

James St. John: Rhyolite (Palisade Rhyolite, North Shore Volcanic Group, Mesoproterozoic, 1096-1097 Ma; Rt. 1 roadcut just north of Ilgen City, Minnesota, USA) 10

James St. John: Rhyolite (Palisade Rhyolite, North Shore Volcanic Group, Mesoproterozoic, 1096-1097 Ma; Rt. 1 roadcut just north of Ilgen City, Minnesota, USA) 11

James St. John: Rhyolite (Palisade Rhyolite, North Shore Volcanic Group, Mesoproterozoic, 1096-1097 Ma; Rt. 1 roadcut just north of Ilgen City, Minnesota, USA) 12

James St. John: Rhyolite (Palisade Rhyolite, North Shore Volcanic Group, Mesoproterozoic, 1096-1097 Ma; Rt. 1 roadcut just north of Ilgen City, Minnesota, USA) 13

James St. John: Deformed flow layering in rhyolitic rheoignimbrite (Palisade Rhyolite, North Shore Volcanic Group, Mesoproterozoic, 1096-1097 Ma; Rt. 1 roadcut just north of Ilgen City, Minnesota, USA) 1

James St. John: Deformed flow layering in rhyolitic rheoignimbrite (Palisade Rhyolite, North Shore Volcanic Group, Mesoproterozoic, 1096-1097 Ma; Rt. 1 roadcut just north of Ilgen City, Minnesota, USA) 2