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Mineral Resources > Online Spatial Data > Geology > by state > Minnesota Geology

Geologic units in Carlton county, Minnesota

Metabasalt, metadiabase, and metasedimentary rocks metamorphosed to lower greenschist facies (Early Proterozoic) at surface, covers 0.7 % of this area

Metabasalt, metadiabase, and metasedimentary rocks metamorphosed to lower greenschist facies - Includes fragmental volcanic rocks, mafic hypabyssal intrusions, graywacke, graphitic argillite and oxide iron-formation

Lithology: metavolcanic rock; metasedimentary rock; graywacke; argillite; iron formation

Mille Lacs Group and related rocks of the Penokean fold-and-thrust bets; Graphitic schist, phyllite and slate interbedded on a fine scale (Early Proterozoic) at surface, covers 0.4 % of this area

Mille Lacs Group and related rocks of the Penokean fold-and-thrust belt; Graphitic schist, phyllite and slate interbedded on a fine scale

Lithology: schist; phyllite; slate

Chengwatana Volcanic Group (Middle Proterozoic) at surface, covers 1 % of this area

Chengwatana Volcanic Group - Basalt and related volcanogenic and interflow sedimentary rocks in east-central Minnesota

Lithology: basalt; rhyolite; clastic

Mille Lacs Group and related rocks of the Penokean fold-and-thrust belt; Metagraywacke, metasiltstone, and a variety of schistose rocks metamorphosed to the amphibolite facies (Early Proterozoic) at surface, covers 7 % of this area

Mille Lacs Group and related rocks of the Penokean fold-and-thrust belt; Metagraywacke, metasiltstone, and a variety of schistose rocks metamorphosed to the amphibolite facies

Lithology: metasedimentary rock; schist

Mille Lacs Group and related rocks of the Penokean fold-and-thrust belt; Metabasalt, metadiabase, and metasedimentary rocks metamorphosed to lower amphibolite facies (Early Proterozoic) at surface, covers 15 % of this area

Mille Lacs Group and related rocks of the Penokean fold-and-thrust belt; Metabasalt, metadiabase, and metasedimentary rocks metamorphosed to lower amphibolite facies - Includes fragmental volcanic rocks, mafic hypabyssal intrusions, graphitic argillite, and oxide iron-formation

Lithology: metavolcanic rock; diabase; metasedimentary rock; argillite; iron formation

Hinckley Sandstone (Middle Proterozoic) at surface, covers 9 % of this area

Hinckley Sandstone - Buff to tan quartz arenite of lacustrine and eolian origin.

Lithology: arenite

Animikie Group; Shale, siltstone, feldspathic graywacke, and associated volcaniclastic rocks (Early Proterozoic) at surface, covers 51 % of this area

Animikie Group; Shale, siltstone, feldspathic graywacke, and associated volcaniclastic rocks - Includes the Rove Formation in Cook County, the Virginia Formation in St. Louis, Itasca, and Lake Counties, and the Thomson Formation in Carlton County

Lithology: shale; siltstone; graywacke; mixed clastic/volcanic

Fond du Lac Formation (Middle Proterozoic) at surface, covers 16 % of this area

Fond du Lac Formation - Red to dark-brown shale, feldspathic sandstone, and arkose of fluvial origin. Includes the Oldenberg Point Member, a pronounced basal unit of quartz-pebble conglomerate in the Duluth area.

Lithology: shale; sandstone; arkose; conglomerate

Chengwatana Volcanic Group (Middle Proterozoic) at surface, covers < 0.1 % of this area

Chengwatana Volcanic Group - Gray basalt flows, interflow breccia, tuff, and minor sedimentary rocks

Lithology: basalt

Bayfield Group; Orienta Sandstone (Middle Proterozoic) at surface, covers 0.1 % of this area

Bayfield Group; Orienta Sandstone - Poorly sorted arkosic sandstone

Lithology: arkose

Mille Lacs Group and related rocks of the Penokean fold-and-thrust belt; Graphitic schist, slate, and silicate iron-formation metamorphosed to the lower greenschist facies and related conditions (Early Proterozoic) at surface, covers 0.3 % of this area

Mille Lacs Group and related rocks of the Penokean fold-and-thrust belt; Graphitic schist, slate, and silicate iron-formation metamorphosed to the lower greenschist facies and related conditions - Includes substantial quantities of mafic to intermediate igneous rocks

Lithology: schist; slate; iron formation

Bayfield Group; Devil's Island Sandstone (Middle Proterozoic) at surface, covers 0.1 % of this area

Bayfield Group; Devil's Island Sandstone - Well-sorted quartzose sandstone

Lithology: sandstone