State | Wisconsin |
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Name | Powder Mill Group; Kallander Creek Volcanics |
Geologic age | Middle Proterozoic |
Lithologic constituents |
Major
Igneous > Volcanic > Mafic-volcanic > Basalt (Flow)Basalt, andesite and lesser rhyolite flows. Basalt flows near base of the formation contain plagioclase phenocrysts, some in radiating clusters
Minor
Igneous > Volcanic > Mafic-volcanic > Andesite (Flow)Basalt, andesite and lesser rhyolite flows. Basalt flows near base of the formation contain plagioclase phenocrysts, some in radiating clusters
Igneous > Volcanic > Felsic-volcanic > Rhyolite (Flow)Basalt, andesite and lesser rhyolite flows. Basalt flows near base of the formation contain plagioclase phenocrysts, some in radiating clusters
|
References | Davis, D.W., and Green, J.C., 1997, Geochronology of the North American Midcontinent rift in western Lake Superior and implications for its geodynamic evolution: Canadian Journal of Earth Sciences, v. 34, pp. 476-488.Zartman and others, 1997, U-Th-Pb zircon ages of some Keweenawan Supergroup rocks from the south shore of Lake Superior: Canadian Journal of Earth Sciences, v. 34, p. 549-561.Cannon, W.F., Kress, T.H., Sutphin, D.M., Morey, G.B., Meints, Joyce, and Barber-Delach, Robert, 1997, Digital Geologic Map and mineral deposits of the Lake Superior Region, Minnesota, Wisconsin, Michigan: USGS Open-File Report 97-455 (version 3, Nov. 1999), scale 1:500,000.https://pubs.er.usgs.gov/publication/ofr97455 |
NGMDB product | |
Counties | Ashland - Bayfield - Iron |