The Penokean orogeny in the Lake Superior region

Iron formations: A global record of Neoarchaean to Palaeoproterozoic environmental history

“…Despite poor exposure, these iron deposits are easily traceable by magnetic anomalies. Correlative and texturally similar GIF are also recognised in the northern part of the Superior Craton in the Hudson Bay region (Richmond Bay and Belchers islands) and in the Sutton Inliers, and are considered to have been deposited in extensional basins coeval with submarine basaltic volcanism (Fralick et al, 2002;Schulz and Cannon, 2007;Ricketts et al, 1982). Some workers have proposed a back-arc setting (Fralick et al, 2002;Schulz and Cannon, 2007), whereas others have advocated a foreland basin setting (Hoffman, 1987;Ojakangas et al, 2001;Schneider et al, 2002).…”

“…VMS deposits of this age are known in the hinterland to the south of the Animikie Basin (Schulz and Cannon, 2007), in the Labrador Trough (Barrett et al, 1988), and in the Trans-Hudson orogen (Syme and Bailes, 1993). Submarine volcanic rocks of the Pembine-Wausau terrane of northern Wisconsin were deposited at ca.…”

Evidence for oxygenic photosynthesis half a billion years before the Great Oxidation Event

“…The basin has been interpreted as a foreland basin that formed in response to crustal loading during the Penokean orogeny. More recently, however, an analysis based on syntectonic intrusions and sedimentology has launched the notion that the iron formations were formed in extensional (back-arc) basins north of the subduction zone during the earliest stages in the Penokean orogeny 34,35 . The Gunflint Iron Formation contains the shallowest facies in the basin and is dominated by granular iron formation.…”

The Arequipa Massif of Peru: New SHRIMP and isotope constraints on a Paleoproterozoic inlier in the Grenvillian orogen

“…1; Goodge et al, 2004, fig. 16) the age range of 1.76-2.1 Ga of Paleoproterozoic zircon in the San and Camaná-Mollendo domains embraces the Yavapai orogeny (1.7-1.8 and the Penokean and Trans-Hudson orogenies (1.8-2.0 Ga; Schulz and Cannon, 2007;Whitmayer and Karlstrom, 2007). Ir formerly part of Laurentia, the Arequipa Massif would be a relic of the pre-Grenvillian southern of the continent (present coordinates) isolated from the northern Paleoproterozoic belts by younger juvenile belts (Mazatzal and the Granite-Rhyolite 1.7-1.3 Ga; 7).…”