The Vermilion Granitic Complex — A new name for old rocks in northern Minnesota
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- Document: Report (pdf)
- Larger Work: This publication is Chapter A of Shorter contributions to mineralogy and petrology, 1979
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Abstract
The name Vermilion Granitic Complex is introduced for the heterogeneous granitic and migmatitic rocks of Archean (formerly called Precambrian W) age that occur north of the Vermilion district and south of the Kabetogama peninsula in northern Minnesota. The complex consists of the following subdivisions: Lac La Croix Granite, granite-rich migmatite, schist-rich migmatite, quartz-feldspar gneiss, hornblende quartz diorite and diorite, granodiorite and trondhjemite, amphibolite and amphibolite migmatite, older migmatite, biotite schist, Burntside Gneiss, and pegmatite. Because the name Vermilion Granitic Complex is proposed as a more inclusive group term, the more restricted name Vermilion Granite (Grout, 1923) is hereby abandoned. The new name Lac La Croix Granite is proposed for the uniform, light-pink biotite granite that occurs widely in the eastern and central parts of the complex. It is denned as having less than 5 percent of schistose or gneissic inclusions and is therefore more restricted than the Vermilion Granite of Grout (1926), which included substantial amounts of migmatitic rocks. The name Burntside Gneiss is adopted as a replacement for the older term Burntside Granite Gneiss, originally named by Grout (1926). This change is required by the conclusion that the rock is a metamorphosed dacite and not a metamorphosed granite, as formerly interpreted.
Study Area
Publication type | Report |
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Publication Subtype | USGS Numbered Series |
Title | The Vermilion Granitic Complex — A new name for old rocks in northern Minnesota |
Series title | Professional Paper |
Series number | 1124 |
Chapter | A |
DOI | 10.3133/pp1124A |
Year Published | 1980 |
Language | English |
Publisher | U.S. Geological Survey |
Description | iii, 11 p. |
Larger Work Type | Report |
Larger Work Subtype | USGS Numbered Series |
Larger Work Title | Shorter contributions to mineralogy and petrology, 1979 (Professional Paper 1124) |
Country | United States |
State | Minnesota |
Other Geospatial | Vermilion Granitic Complex |
Google Analytic Metrics | Metrics page |