Unit symbol: | PzPxrg |
---|---|
Age range | Paleozoic and Proterozoic (1000 to 443.4 Ma) |
Lithology: | Metamorphic |
Group name: | Four Winds complex of Gilbert and others (1987), Retreat Group, and orthogneiss |
Source map | Karl, S.M., Haeussler, P.J., Himmelberg, G.R., and Brew, D.A., 1998, Unpublished data. |
---|---|
Symbol | Pza |
Unit name | Amphibolite |
Description | Dark green semischist, chlorite schist, subordinate metadiorite, marble, metachert. Dominantly igneous protoliths. Metamorphic minerals include chlorite, biotite, muscovite, hornblende, actinolite, epidote, clinopyroxene, garnet, plagioclase, calcite, graphite, quartz. Pyrite, magnetite, rutile, titanite, apatite, staurolite, anchorite, tourmaline, and possible sillimanite also identified. Amphibolite facies metamorphism predates greenschist facies metamorphism. |
Lithology | Metamorphic |
Label | PzZrg |
---|---|
Description | Retreat Group (restricted) |
Geologic age | Neoproterozoic to Ordovician |
Geologic setting | Metamorphic, undivided |
Lithology | Form | Importance |
---|---|---|
Marble < Metacarbonate < Metasedimentary < Metamorphic | Indeterminate, major | |
Quartzite < Metaclastic < Metasedimentary < Metamorphic | Indeterminate, major | |
Mica-schist < Schist < Metamorphic | Indeterminate, major |