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Mad Indian Group

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Fine-grained feldspathic biotite gneiss; medium to coarse-grained muscovite-biotite-garnet schist; locally kyanite and sillimanite. Many of the schists have been retrograded to chlorite-garnet-quartz-sericite schist. Both mi and migr extensively cut by feldspathic dikes and pegmatites.
State Alabama
Name Mad Indian Group
Geologic age Precambrian to Paleozoic
Lithologic constituents
Major
Metamorphic > Schist > Mica-schistmedium to coarse-grained muscovite-biotite-garnet schist; locally kyanite and sillimanite. Many of the schists have been retrograded to chlorite-garnet-quartz-sericite schist. Commonly includes irregular zones of sericite-quartz schist (+/- garnet) containing finely disseminated graphite, possibly infolded Wedowee Group equivalents.
Metamorphic > Gneiss > Biotite-gneissfine-grained feldspathic biotite gneiss
Minor
Igneous > Plutonic > Granitic > Leucocratic-granitic > Pegmatite (Dike or sill)Extensively cut by feldspathic dikes and pegmatites.
Comments Printed map includes map units 'mi and migr' in one description; split them up here.
References

Szabo, M.W., Osborne, E.W., Copeland, C.W. Jr., and Neathery, T.L., 1988, Geologic Map of Alabama, Geological Survey of Alabama Special Map 220, scale 1:250,000.
NGMDB product
Counties Clay - Cleburne - Randolph